I2NSF Working Group                                        S. Hares, Ed.
Internet-Draft                                                    Huawei
Intended status: Standards Track                           J. Jeong, Ed.
Expires: September 9, 2021 15 February 2022                                         J. Kim
                                                 Sungkyunkwan University
                                                            R. Moskowitz
                                                          HTT Consulting
                                                                  Q. Lin
                                                                  Huawei
                                                           March 8,
                                                          14 August 2021

                    I2NSF Capability YANG Data Model
               draft-ietf-i2nsf-capability-data-model-16
               draft-ietf-i2nsf-capability-data-model-17

Abstract

   This document defines an information model and the corresponding YANG
   data model for the capabilities of various Network Security Functions
   (NSFs) in the Interface to Network Security Functions (I2NSF)
   framework to centrally manage the capabilities of the various NSFs.

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   This Internet-Draft will expire on September 9, 2021. 15 February 2022.

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Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2   3
   2.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   4
   3.  Capability  Information Model Design . . . of I2NSF NSF Capability . . . . . . . . . .   4
     3.1.  Design Principles and ECA Policy Model Overview . . . . .   5
     3.2.  Matched Policy Rule . . .  . . . . . . . . . . . . . . . .   8
     3.3.   5
     3.2.  Conflict, Resolution Strategy and Default Action  . . . .   8
   4.  Overview of YANG Data Model . . . . . . . . . . . . . . . . .   9  10
   5.  YANG Tree Diagram . . . . . . . . . . . . . . . . . . . . . .  12
     5.1.  Network Security Function (NSF) Capabilities  . . . . . .  12
   6.  YANG Data Model of I2NSF NSF Capability . . . . . . . . . . .  15
   7.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  59  48
   8.  Privacy Considerations  . . . . . . . . . . . . . . . . . . .  59  49
   9.  Security Considerations . . . . . . . . . . . . . . . . . . .  60  49
   10. References  . . . . . . . . . . . . . . . . . . . . . . . . .  60  51
     10.1.  Normative References . . . . . . . . . . . . . . . . . .  60  51
     10.2.  Informative References . . . . . . . . . . . . . . . . .  65  55
   Appendix A.  Configuration Examples . . . . . . . . . . . . . . .  67  57
     A.1.  Example 1: Registration for the Capabilities of a General
           Firewall  . . . . . . . . . . . . . . . . . . . . . . . .  67  57
     A.2.  Example 2: Registration for the Capabilities of a Time-
           based
           Time-based Firewall . . . . . . . . . . . . . . . . . . . . .  70  59
     A.3.  Example 3: Registration for the Capabilities of a Web
           Filter  . . . . . . . . . . . . . . . . . . . . . . . . .  72  61
     A.4.  Example 4: Registration for the Capabilities of a
           VoIP/VoLTE VoIP/
           VoLTE Filter  . . . . . . . . . . . . . . . . . . . .  72 . .  61
     A.5.  Example 5: Registration for the Capabilities of a HTTP and
           HTTPS Flood Mitigator . . . . . . . . . . . . . . . .  73 . .  62
   Appendix B.  Acknowledgments  . . . . . . . . . . . . . . . . . .  74  63
   Appendix C.  Contributors . . . . . . . . . . . . . . . . . . . .  75  64
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  77  65

1.  Introduction

   As the industry becomes more sophisticated and network devices (e.g.,
   Internet-of-Things (IoT) devices, autonomous vehicles, and
   smartphones using Voice over IP (VoIP) and Voice over LTE (VoLTE))
   require advanced security protection in various scenario, scenarios, security
   service providers have a lot of problems described in [RFC8192]. [RFC8192] to
   provide such network devices with efficient and reliable security
   services in network infrastructure.  To resolve these problems, this
   document specifies the information and data models of the
   capabilities of Network Security Functions (NSFs) in a framework of
   the Interface to Network Security Functions (I2NSF) [RFC8329].

   NSFs produced by multiple security vendors provide various security
   capabilities to customers.  Multiple NSFs can be combined together to
   provide security services over the given network traffic, regardless
   of whether the NSFs are implemented as physical or virtual functions.
   Security Capabilities describe the functions that Network Security
   Functions (NSFs) are available to can provide for security policy
   enforcement purposes. enforcement.
   Security Capabilities are independent of the actual security control mechanisms policy
   that will implement them. the functionality of the NSF.

   Every NSF SHOULD be described with the set of capabilities it offers.
   Security Capabilities enable security functionality to be described
   in a vendor-neutral manner.  That is, it is not needed to refer to a
   specific product or technology when designing the network; rather,
   the functions characterized by their capabilities are considered.  Security Capabilities are a market
   enabler, providing a way to define customized security protection by
   unambiguously describing the security features offered by a given
   NSF.  Note that this YANG data model outlines an structurizes the NSF monitoring Monitoring
   Interface YANG data model [I-D.ietf-i2nsf-nsf-monitoring-data-model]
   and a the NSF-Facing Interface YANG data model for
   Software-Defined Networking (SDN)-based IPsec flow protection
   [I-D.ietf-i2nsf-sdn-ipsec-flow-protection]. Data Model
   [I-D.ietf-i2nsf-nsf-facing-interface-dm].

   This document provides an information model and the corresponding
   YANG data model [RFC6020][RFC7950] that defines the capabilities of
   NSFs to centrally manage the capabilities of those security devices. NSFs.  The security devices NSFs
   can register their own capabilities into a Network Operator
   Management (Mgmt) System (i.e., Security Controller) with this YANG
   data model through the registration interface [RFC8329].  With the
   database of the capabilities of those security
   devices NSFs that are maintained
   centrally, those security devices NSFs can be more easily managed [RFC8329].

   This YANG data model uses an "Event-Condition-Action" (ECA) policy
   model that is used as the basis for the design of I2NSF Policy as
   described in [RFC8329] and Section 3.1.  The "ietf-i2nsf-capability"
   YANG module defined in this document provides the following features:

   o  Definition for time capabilities of network security functions.

   o

   *  Definition for event capabilities of generic network security
      functions.

   o  Definition for condition capabilities of generic network security functions.

   o

   *  Definition for condition capabilities of advanced network security
      functions.

   o

   *  Definition for action capabilities of generic network security functions.

   o

   *  Definition for resolution strategy capabilities of generic network
      security functions.

   o

   *  Definition for default action capabilities of generic network security
      functions.

2.  Terminology

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in BCP
   14 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.

   This document uses the terminology described in [RFC8329].

   This document follows the guidelines of [RFC8407], uses the common
   YANG types defined in [RFC6991], and adopts the Network Management
   Datastore Architecture (NMDA).  The meaning of the symbols in tree
   diagrams is defined in [RFC8340].

3.  Capability  Information Model Design

   A of I2NSF NSF Capability

   This section provides the I2NSF Capability Information Model (CapIM) (CapIM).
   A CapIM is a formalization of the functionality that an NSF
   advertises.  This enables the precise specification of what an NSF
   can do in terms of security policy enforcement, so that computer-based computer-
   based tasks can unambiguously refer to, use, configure, and manage
   NSFs.  Capabilities MUST be defined in a vendor- and technology-independent technology-
   independent manner (e.g., regardless of the differences among vendors
   and individual products).

   Humans can refer to categories of security controls and understand
   each other.  For instance, network security experts agree on what is
   meant by the terms "NAT", "filtering", and "VPN concentrator".  As a
   further example, network security experts unequivocally refer to
   "packet filters" as stateless devices that allow or deny packet
   forwarding based on various conditions (e.g., source and destination
   IP addresses, source and destination ports, and IP protocol type
   fields) [Alshaer].

   However, more information is required in case of other devices, like
   stateful firewalls or application layer filters.  These devices
   filter packets or communications, but there are differences in the
   packets and communications that they can categorize and the states
   they maintain.  Humans deal with these differences by asking more
   questions to determine the specific category and functionality of the
   device.  Machines can follow a similar approach, which is commonly
   referred to as question-answering [Hirschman] [Galitsky].  In this
   context, the CapIM and the derived data model can provide important
   and rich information sources.

   Analogous considerations can be applied for channel protection
   protocols, where we all understand that they will protect packets by
   means of symmetric algorithms whose keys could have been negotiated
   with asymmetric cryptography, but they may work at different layers
   and support different algorithms and protocols.  To ensure
   protection, these protocols apply integrity, optionally
   confidentiality, anti-reply protections, and authentication.

   The CapIM is intended to clarify these ambiguities by providing a
   formal description of NSF functionality.  The set of functions that
   are advertised MAY be restricted according to the privileges of the
   user or application that is viewing those functions.  I2NSF
   Capabilities enable unambiguous specification of the security
   capabilities available in a (virtualized) networking environment, and
   their automatic processing by means of computer-based techniques.

   This CapIM includes enabling a security controller in an I2NSF
   framework [RFC8329] to properly identify and manage NSFs, and allow
   NSFs to properly declare their functionality through a Developer's
   Management System (DMS) [RFC8329] , [RFC8329], so that they can be used in the
   correct way.

3.1.  Design Principles and ECA Policy Model Overview

   -po

   This document defines an information model for representing NSF
   capabilities.  Some basic design principles for security capabilities
   and the systems that manage them are:

   o

   *  Independence: Each security capability SHOULD be an independent
      function, with minimum overlap or dependency on other
      capabilities.  This enables each security capability to be
      utilized and assembled together freely.  More importantly, changes
      to one capability SHOULD NOT affect other capabilities.  This
      follows the Single Responsibility Principle [Martin] [OODSRP].

   o

   *  Abstraction: Each capability MUST be defined in a vendor-
      independent manner.

   o

   *  Advertisement: A dedicated, well-known interface Registration Interface
      [I-D.ietf-i2nsf-registration-interface-dm] MUST be used to
      advertise and register the capabilities of each NSF.  This same
      interface MUST be used by other I2NSF Components to determine what
      Capabilities are currently available to them.

   o

   *  Execution: Dedicated, well-known interfaces NSF-Facing Interface
      [I-D.ietf-i2nsf-nsf-facing-interface-dm] and NSF Monitoring
      Interface [I-D.ietf-i2nsf-nsf-monitoring-data-model] MUST be used
      to configure and monitor the use of a capability, resepectively. capability into an NSF and monitor the
      NSF, respectively.  These provide a standardized ability to
      describe its functionality, and report its processing results, resepectively.
      respectively.  These facilitate multi-vendor interoperability.

   o

   *  Automation: The system MUST have the ability to auto-discover,
      auto-negotiate, and auto-update its security capabilities (i.e.,
      without human intervention).  These features are especially useful
      for the management of a large number of NSFs.  They are essential
      for adding smart services (e.g., refinement, analysis, capability
      reasoning, and optimization) to the security scheme employed.
      These features are supported by many design patterns, including
      the Observer Pattern [OODOP], the Mediator Pattern [OODMP], and a
      set of Message Exchange Patterns [Hohpe].

   o  Scalability: The management system SHOULD have the capability to
      scale up/down or scale in/out.  Thus, it  Registration Interface
      [I-D.ietf-i2nsf-registration-interface-dm] can meet various
      performance requirements derived from changeable network traffic
      or service requests. register the
      capabilities of NSFs with the security controller from the request
      of Developer's Management System providing NSFs and the
      corresponding security capabilities.  Also, this interface can
      send a query to Developer's Management System in order to find an
      NSF to satisfy the requested security capability from the security
      controller that receives a security policy.

   *  Scalability: The management system SHOULD have the capability to
      scale up/down or scale in/out.  Thus, it can meet various
      performance requirements derived from changeable network traffic
      or service requests.  In addition, security capabilities that are
      affected by scalability changes SHOULD support reporting
      statistics to the security controller to assist its decision on
      whether it needs to invoke scaling or not.  NSF Monitoring
      Interface [I-D.ietf-i2nsf-nsf-monitoring-data-model] can observe
      the performance of NSFs to let the security controller decide
      scalability changes of the NSFs.

   Based on the above principles, this document defines a capability
   model that enables an NSF to register (and hence advertise) its set
   of capabilities that other I2NSF Components can use.  These
   capabilities MAY MUST have their access control restricted by a policy;
   this is out of scope for this document.  The set of capabilities
   provided by a given set of NSFs unambiguously defines the security
   services offered by the set of NSFs used.  The security controller
   can compare the requirements of users and applications with the set
   of capabilities that are currently available in order to choose which
   capabilities of which NSFs are needed to meet those requirements.
   Note that this choice is independent of vendor, and instead relies
   specifically on the capabilities (i.e., the description) of the
   functions provided.

   Furthermore, when an unknown threat (e.g., zero-day exploits NSFs are subject to the updates of security capabilities
   and
   unknown malware) is reported by an NSF, software to cope with newly found security attacks or threats,
   hence new capabilities may be created, and/or existing capabilities
   may be updated (e.g., by updating its signature and algorithm).  This results in enhancing the
   existing NSFs (and/or creating new NSFs) to address the new threats.  New
   capabilities may be sent to and stored in a centralized repository,
   or stored separately in a vendor's local repository.  In either case, a standard interface facilitates
   Registration Interface can facilitate this update process. process to
   Developer's Management System to let the security controller update
   its repository for NSFs and their security capabilities.

   The "Event-Condition-Action" (ECA) policy model in [RFC8329] is used
   as the basis for the design of the capability model; definitions of
   all I2NSF policy-related terms are also defined in [RFC8329]. The following
   three terms define the structure and behavior of an I2NSF imperative
   policy rule:

   o

   *  Event: An Event is defined as any important occurrence in time of
      a change in the system being managed, and/or in the environment of
      the system being managed.  When used in the context of I2NSF
      Policy Rules, it is used to determine whether the condition clause
      of an I2NSF Policy Rule can be evaluated or not.  Examples of an
      I2NSF Event include time and user actions (e.g., logon, logoff,
      and actions that violate an ACL).

   o

   *  Condition: A condition is defined as a set of attributes,
      features, and/or values that are to be compared with a set of
      known attributes, features, and/or values in order to determine
      whether or not the set of actions in that (imperative) I2NSF
      Policy Rule can be executed or not.  Examples of I2NSF conditions
      include matching attributes of a packet or flow, and comparing the
      internal state of an NSF with a desired state.

   o

   *  Action: An action is used to control and monitor aspects of flow-
      based NSFs
      to handle packets or flows when the event and condition clauses
      are satisfied.  NSFs provide security functions by executing
      various Actions.  Examples of I2NSF actions include providing
      intrusion detection and/or protection, web and flow filtering, and
      deep packet inspection for packets and flows.

   An I2NSF Policy Rule is made up of three Boolean clauses: an Event
   clause, a Condition clause, and an Action clause.  This structure is
   also called an ECA (Event-Condition-Action) Policy Rule.  A Boolean
   clause is a logical statement that evaluates to either TRUE or FALSE.
   It may be made up of one or more terms; if more than one term is
   present, then each term in the Boolean clause is combined using
   logical connectives (i.e., AND, OR, and NOT).

   An I2NSF ECA Policy Rule has the following semantics:

      IF <event-clause> is TRUE

         IF <condition-clause> is TRUE

            THEN execute <action-clause> [constrained by metadata]

         END-IF

      END-IF

   Technically, the "Policy Rule" is really a container that aggregates
   the above three clauses, as well as metadata, which describe the
   characteristics and behaviors of a capability (or an NSF).
   Aggregating metadata enables a business logic to be used to prescribe
   a behavior.  For example, suppose a particular ECA Policy Rule
   contains three actions (A1, A2, and A3, in that order).  Action A2
   has a priority of 10; actions A1 and A3 have no priority specified.
   Then, metadata may be used to restrict the set of actions that can be
   executed when the event and condition clauses of this ECA Policy Rule
   are evaluated to be TRUE; two examples are: (1) only the first action
   (A1) is executed, and then the policy rule returns to its caller, or
   (2) all actions are executed, starting with the highest priority.

   The above ECA policy model is very general and easily extensible.

3.2.  Matched  Conflict, Resolution Strategy and Default Action

   Formally, two I2NSF Policy Rule

   The concept Rules conflict with each other if:

   *  the Event Clauses of a "matched" policy rule is defined as one in which its
   event and condition clauses both each evaluate to true.  To precisely
   describe what an NSF can do in terms TRUE;

   *  the Condition Clauses of security, that a policy rule
   needs each evaluate to describe TRUE;

   *  the events that it can catch, Action Clauses affect the conditions it can
   evaluate, same object in different ways.

   For example, if we have two Policy Rules called R1 and the actions that it can enforce.

   Therefore, the properties to characterize the capabilities of an NSF
   are as follows:

   o  Ac is the set of Actions currently available from the NSF;

   o  Ec is the set of Events that an NSF can catch.  Note that for NSF
      (e.g., a packet filter) that are not able to react to events, this
      set will be empty;

   o  Cc is the set of Conditions currently available from the NSF;

   o  EVc defines the set of Condition Clause Evaluation Rules that can
      be used by the NSF to decide when the Condition Clause is true
      when the results of the individual Conditions under evaluation are
      given.

3.3.  Conflict, Resolution Strategy and Default Action

   Formally, two I2NSF Policy Rules conflict with each other if:

   o  the Event Clauses of each evaluate to TRUE;

   o  the Condition Clauses of each evaluate to TRUE;

   o  the Action Clauses affect the same object in different ways.

   For example, if we have two Policy Rules R2 in the same
   Policy:

      R1: During 8am-6pm, if traffic is external, then run through FW
      firewall

      R2: During 7am-8pm, conduct anti-malware investigation run anti-virus

   There is no conflict between the two policy rules R1 and R2, since
   the actions are different.  However, consider these two rules: rules called
   R3 and R4:

      R3: During 8am-6pm, 9am-6pm, allow John gets GoldService to access social networking service
      websites

      R4: During 10am-4pm, FTP from 9am-6pm, disallow all users gets BronzeService to access social networking
      service websites

   The two policy rules R3 and R4 are now in conflict, between the hours
   of 10am 9am and 4pm, 6pm, because the actions of R3 and R4 are different and
   apply to the same user (i.e., John).

   Conflicts theoretically compromise the correct functioning of devices
   (as happened for routers several year ago).
   devices.  However, NSFs have been designed to cope with these issues.
   Since conflicts are originated by simultaneously matching rules, an
   additional process decides the action to be applied, e.g., among the ones
   actions which the matching rule would have enforced.  This process is
   described by means of a resolution strategy for conflicts.  The
   finding and handling of conflicted matching rules is performed by
   resolution strategies in the security controller.  The implementation
   of such resolution strategies is out of scope for I2NSF.

   On the other hand, it may happen that, if an event is caught, none of
   the policy rules matches the event. condition.  Note that a packet or flow
   is handled only when it matches both the event and condition of a
   policy rule according to the ECA policy model.  As a simple case, no
   condition in the rules may match a packet arriving at the border
   firewall.  In this case, the packet is usually dropped, that is, the
   firewall has a default behavior of packet dropping in order to manage
   the cases that are not covered by specific rules.

   Therefore, this document introduces another security capability that
   serves to characterize valid policies two further capabilities for an
   NSF that solve to handle security policy conflicts with resolution strategies
   and enforce a default actions action if no rules
   match:

   o  RSc is the set of match.

   *  Resolution Strategies that Strategies: They can be used to specify how to resolve
      conflicts that occur between the actions of the same or different
      policy rules that are matched and contained in this particular
      NSF;

   o  Dc defines the notion of a

   *  Default action.  This action Action: It provides the default behavior to be executed
      when there are no other alternatives.  This action can be either
      an explicit action or a set of actions.

4.  Overview of YANG Data Model

   This section provides an overview of how the YANG data model can be
   used in the I2NSF framework described in [RFC8329].  Figure 1 shows
   the capabilities (e.g., firewall and web filter) of NSFs in the I2NSF
   Framework.  As shown in this figure, an NSF a Developer's Management System
   (DMS) can register NSFs and the their capabilities that the NSFs can
   support. with a Security
   Controller.  To register NSFs in this way, the DMS utilizes this the
   standardized capability YANG data model in this document through the
   I2NSF Registration Interface [RFC8329].  That is, this Registration
   Interface uses the YANG module described in this document to describe
   the capabilities of an NSF that is registered with the Security
   Controller.  With the database of  As described in [RFC8192], with the capabilities usage of
   Registration Interface and the NSFs that
   are maintained centrally, YANG module in this document, the NSFs
   manufactured by multiple vendors can be more easily managed, which
   can resolve many of managed together by the problems described
   Security Controller in [RFC8192]. a centralized way and be updated dynamically
   by each vendor as the NSF has software or hardware updates.

   In Figure 1, a new NSF at a Developer's Management System has
   capabilities of Firewall (FW) and Web Filter (WF), which are denoted
   as (Cap = {FW, WF}), to support Event-Condition-Action (ECA) policy
   rules where 'E', 'C', and 'A' mean "Event", "Condition", and
   "Action", respectively.  The condition involves IPv4 or IPv6
   datagrams, and the action includes "Allow" and "Deny" for those
   datagrams.

   Note that the NSF-Facing Interface [RFC8329] is used for by the Security
   Controller to configure the security policy rules of generic NSFs
   (e.g., firewall) and advanced NSFs (e.g., anti-virus
   firewall and Distributed-
   Denial-of-Service Distributed-Denial-of-Service (DDoS) attack mitigator)
   with the capabilities of the NSFs registered with the Security
   Controller.

      +------------------------------------------------------+
      |  I2NSF User (e.g., Overlay Network Mgmt, Enterprise  |
      |  Network Mgmt, another network domain's mgmt, etc.)  |
      +--------------------+---------------------------------+
          I2NSF            ^
 Consumer-Facing Interface |
                           |
                           v                 I2NSF
         +-----------------+------------+  Registration +-------------+
         | Network Operator Mgmt System |   Interface   | Developer's |
         | (i.e., Security Controller)  |<-------------->|  |<------------->| Mgmt System |
         +-----------------+------------+               +-------------+
                           ^                                New NSF
                           |                          Cap = {FW, WF}
             I2NSF         |                          E = {}
      NSF-Facing Interface |                          C = {IPv4, IPv6}
                           |                          A = {Allow, Deny}
                           v
      +---------------+----+------------+-----------------+
      |               |                 |                 |
  +---+---+       +---+---+         +---+---+         +---+---+
  | NSF-1 |  ...  | NSF-m |         | NSF-1 |   ...   | NSF-n |
  +-------+       +-------+         +-------+         +-------+
    NSF-1           NSF-m             NSF-1             NSF-n
 Cap = {FW, WF}    Cap = {FW, WF}    Cap = {FW, WF}    Cap = {FW, WF}
 E = {}            E = {user}        E = {dev}         E = {time}
 C = {IPv4}        C = {IPv6}        C = {IPv4, IPv6}  C = {IPv4}
 A = {Allow, Deny} A = {Allow, Deny} A = {Allow, Deny} A = {Allow, Deny}

  Developer's Mgmt System A           Developer's Mgmt System B

          Figure 1: Capabilities of NSFs in I2NSF Framework

   A use case of an NSF with the capabilities of firewall and web filter
   is described as follows.

   o

   *  If a network administrator wants to apply security policy rules to
      block malicious users with firewall and web filter, it is a
      tremendous burden for a network administrator to apply all of the
      needed rules to NSFs one by one.  This problem can be resolved by
      managing the capabilities of NSFs as described in this document.

   o

   *  If a network administrator wants to block IPv4 or IPv6 packets
      from malicious users, the network administrator sends a security
      policy rule to block the users to the Network Operator Management
      System (i.e., Security Controller) using the I2NSF Consumer-Facing
      Interface.

   o

   *  When the Network Operator Management System receives the security
      policy rule, it automatically sends that security policy rule to
      appropriate NSFs (i.e., NSF-m in Developer's Management System A
      and NSF-1 in Developer's Management System B) which can support
      the capabilities (i.e., IPv6).  This lets an I2NSF User not
      consider which specific NSF(s) will work for the security policy
      rule.

   o

   *  If NSFs encounter the suspicious IPv4 or IPv6 packets of malicious
      users, they can filter the packets out according to the configured
      security policy rule.  Therefore, the security policy rule against
      the malicious users' packets can be automatically applied to
      appropriate NSFs without human intervention.

5.  YANG Tree Diagram

   This section shows a YANG tree diagram of capabilities of network
   security functions, as defined in the Section 3.

5.1.  Network Security Function (NSF) Capabilities

   This section explains a YANG tree diagram of NSF capabilities and its
   features.  Figure 2 shows a YANG tree diagram of NSF capabilities.
   The NSF capabilities in the tree include time capabilities, event
   capabilities, condition capabilities, action capabilities, resolution
   strategy capabilities, and default action capabilities.  Those
   capabilities can be tailored or extended according to a vendor's
   specific requirements.  Refer to the NSF capabilities information
   model for detailed discussion in Section 3.

   module: ietf-i2nsf-capability
     +--rw nsf* [nsf-name]
        +--rw nsf-name                            string
        +--rw time-capabilities*                  enumeration directional-capabilities*           identityref
        +--rw event-capabilities
        |  +--rw system-event-capability*   identityref
        |  +--rw system-alarm-capability*   identityref
        |  +--rw time-capabilities*         identityref
        +--rw condition-capabilities
        |  +--rw generic-nsf-capabilities
        |  |  +--rw ipv4-capability*     identityref
        |  |  +--rw icmp-capability* ipv6-capability*     identityref
        |  |  +--rw ipv6-capability* icmpv4-capability*   identityref
        |  |  +--rw icmpv6-capability*   identityref
        |  |  +--rw tcp-capability*      identityref
        |  |  +--rw udp-capability*      identityref
        |  |  +--rw sctp-capability*     identityref
        |  |  +--rw dccp-capability*     identityref
        |  +--rw advanced-nsf-capabilities
        |  |  +--rw anti-virus-capability* anti-ddos-capability*              identityref
        |  |  +--rw anti-ddos-capability* ips-capability*                    identityref
        |  |  +--rw ips-capability* url-capability*                    identityref
        |  |  +--rw url-capability* voip-volte-filtering-capability*   identityref
        |  +--rw context-capabilities
        |     +--rw application-filter-capabilities*   identityref
        |     +--rw target-capabilities*               identityref
        |     +--rw voip-volte-capability* user-condition-capabilities*       identityref
        |     +--rw context-capabilities* geography-capabilities*            identityref
        +--rw action-capabilities
        |  +--rw ingress-action-capability*   identityref
        |  +--rw egress-action-capability*    identityref
        |  +--rw log-action-capability*       identityref
        +--rw resolution-strategy-capabilities*   identityref
        +--rw default-action-capabilities*        identityref
        +--rw ipsec-method*                       identityref

      Figure 2: YANG Tree Diagram of Capabilities of Network Security
                                 Functions

   The data model in this document provides identities for the
   capabilities of NSFs.  Every identity in the data model represents
   the capability of an NSF.  Each identity is explained in the
   description of the identity.

   Event capabilities are used to specify the capabilities that describe
   an event that would trigger the evaluation of the condition clause of
   the I2NSF Policy Rule.  The defined event capabilities are system
   event, system alarm, and time.  Time capabilities are used to specify
   the capabilities which describe when to execute the I2NSF policy
   rule.  The time capabilities are defined in terms of absolute time
   and periodic time.  The absolute time means the exact time to start
   or end.  The periodic time means repeated time like day, week, month,
   or month.

   Event capabilities are used to specify the capabilities that describe
   an event that would trigger the evaluation of the condition clause of
   the I2NSF Policy Rule.  The defined event capabilities are system
   event and system alarm. year.

   Condition capabilities are used to specify capabilities of a set of
   attributes, features, and/or values that are to be compared with a
   set of known attributes, features, and/or values in order to
   determine whether a set of actions needs to be executed or not so
   that an imperative I2NSF policy rule can be executed.  In this
   document, two kinds of condition capabilities are used to classify
   different capabilities of NSFs such as generic-nsf-capabilities for
   generic NSFs and advanced-nsf-capabilities for advanced NSFs.
   advanced-nsf-capabilities.  First, the generic-nsf-capabilities
   define the common capabilities of NSFs
   such as that operate on packet header for layer 2 (i.e., Ethernet
   capability), layer 3 (i.e., IPv4 capability, IPv6 capability, ICMPv4
   capability, and ICMPv6 capability.), and layer 4 (i.e., TCP
   capability, UDP capability, SCTP capability, DCCP capability, ICMP capability, and
   ICMPv6 capability. DCCP capability).
   Second, the advanced-nsf-capabilities define
   advanced capabilities of NSFs that operate on
   features different from the generic-nsf-capabilities, e.g., the
   payload, cross flow state, application layer, traffic statistics,
   network behavior, etc.  This document defines the advanced-nsf into
   two categories such as content-security-control and attack-
   mitigation-control.

   *  Content security control is an NSF that evaluates the payload of a
      packet, such as anti-virus capability, anti-
   DDoS capability, Intrusion Prevention System (IPS) (IPS), URL-Filtering,
      Antivirus, and VoIP/VoLTE Filter.

   *  Attack mitigation control is an NSF that mitigates an attack such
      as anti-DDoS (DDoS-mitigator).

   The advanced-nsf can be extended with other types of NSFs.  This
   document only provides five advanced-nsf capabilities, i.e., IPS
   capability, HTTP URL-Filtering capability, Antivirus capability, VoIP/
   VoLTE Filter capability, and VoIP/VoLTE Anti-DDoS capability.  Note that VoIP
   and VoLTE are merged into a single capability in this document
   because VoIP and VoLTE use the Session Initiation Protocol (SIP)
   [RFC3261] for a call setup.  See Section 3.1 for more information
   about the condition in the ECA policy model.

   The context capabilities provide extra information for the condition.
   The given context conditions are application filter, target, user
   condition, and geography location.  The application filter capability
   is capability in matching the packet based on the application
   protocol, such as HTTP, HTTPS, FTP, etc.  The target capability is
   capability in matching the type of the target devices, such as PC,
   IoT, Network Infrastructure devices, etc.  The user condition is
   capability in matching the users of the network by mapping each user
   ID to an IP address.  Users can be combined into one group.  The
   geography location capability is capability in matching the
   geographical location of a source or destination of a packet.

   Action capabilities are used to specify the capabilities that
   describe the control and monitoring aspects of flow-based NSFs when
   the event and condition clauses are satisfied.  The action
   capabilities are defined as ingress-action capability, egress-action
   capability, and log-action capability.  See Section 3.1 for more
   information about the action in the ECA policy model.  Also, see
   Section 7.2 (NSF-Facing Flow Security Policy Structure) in [RFC8329]
   for more information about the ingress and egress actions.  In
   addition, see Section 9.1 (Flow-Based NSF Capability
   Characterization) in [RFC8329] and Section 7.5 (NSF Logs) in
   [I-D.ietf-i2nsf-nsf-monitoring-data-model] for more information about
   logging at NSFs.

   Resolution strategy capabilities are used to specify the capabilities
   that describe conflicts that occur between the actions of the same or
   different policy rules that are matched and contained in this
   particular NSF.  The resolution strategy capabilities are defined as
   First Matching Rule (FMR), Last Matching Rule (LMR), Prioritized
   Matching Rule (PMR), Prioritized Matching Rule with Errors (PMRE),
   and Prioritized Matching Rule with No Errors (PMRN).  See Section 3.3 3.2
   for more information about the resolution strategy.

   Default action capabilities are used to specify the capabilities that
   describe how to execute I2NSF policy rules when no rule matches a
   packet.  The default action capabilities are defined as pass, drop,
   alert,
   rate-limit, and mirror.  See Section 3.3 3.2 for more information about
   the default action.

   IPsec method capabilities are used to specify capabilities of how to
   support an Internet Key Exchange (IKE) [RFC7296] for the security
   communication.  The default action capabilities are defined as IKE or
   IKE-less.  See [I-D.ietf-i2nsf-sdn-ipsec-flow-protection] for more
   information about the SDN-based IPsec flow protection in I2NSF.

6.  YANG Data Model of I2NSF NSF Capability

   This section introduces a YANG module for NSFs' capabilities, as
   defined in the Section 3.

   This YANG module imports from [RFC6991].

   It makes references to

   o

   *  [RFC0768]

   o

   *  [RFC0791]

   o

   *  [RFC0792]

   o

   *  [RFC0793]

   o
   *  [RFC2474]

   o

   *  [RFC3168]

   o

   *  [RFC3261]

   o

   *  [RFC3501]

   *  [RFC4340]

   o

   *  [RFC4443]

   o

   *  [RFC4960]

   o

   *  [RFC5595]

   o

   *  [RFC6335]

   o

   *  [RFC6437]

   o

   *  [RFC6691]

   o

   *  [RFC6864]

   o

   *  [RFC7230]

   o

   *  [RFC7231]

   o

   *  [RFC7296]
   o

   *  [RFC7323]

   o

   *  [RFC8200]

   o

   *  [RFC8329]

   o

   *  [RFC8519]

   o

   *  [RFC8805]

   o

   *  [IANA-Protocol-Numbers]

   o

   *  [I-D.ietf-tcpm-rfc793bis]

   o

   *  [I-D.ietf-tcpm-accurate-ecn]

   o

   *  [I-D.ietf-tsvwg-udp-options]

   o
   *  [I-D.ietf-i2nsf-nsf-monitoring-data-model]

   o  [I-D.ietf-i2nsf-sdn-ipsec-flow-protection]

   <CODE BEGINS> file "ietf-i2nsf-capability@2021-03-08.yang" "ietf-i2nsf-capability@2021-08-14.yang"
   module ietf-i2nsf-capability {
     yang-version 1.1;
     namespace
       "urn:ietf:params:xml:ns:yang:ietf-i2nsf-capability";
     prefix
       nsfcap;

     organization
       "IETF I2NSF (Interface to Network Security Functions)
        Working Group";

     contact
       "WG Web: <http://tools.ietf.org/wg/i2nsf>
        WG List: <mailto:i2nsf@ietf.org>

        Editor: Jaehoon Paul Jeong
        <mailto:pauljeong@skku.edu>

        Editor: Jinyong Tim Kim
        <mailto:timkim@skku.edu>

        Editor: Patrick Lingga
        <mailto:patricklink@skku.edu>

        Editor: Susan Hares
        <mailto:shares@ndzh.com>";

     description
       "This module is a YANG module for I2NSF Network Security
        Functions (NSFs)'s Capabilities.

        Copyright (c) 2021 IETF Trust and the persons identified as
        authors of the code. All rights reserved.

        Redistribution and use in source and binary forms, with or
        without modification, is permitted pursuant to, and subject to
        the license terms contained in, the Simplified BSD License set
        forth in Section 4.c of the IETF Trust's Legal Provisions
        Relating to IETF Documents
        (https://trustee.ietf.org/license-info).

        This version of this YANG module is part of RFC XXXX
        (https://www.rfc-editor.org/info/rfcXXXX); see the RFC itself
        for full legal notices.";

     // RFC Ed.: replace XXXX with an actual RFC number and remove
     // this note.

     revision "2021-03-08"{ "2021-08-14"{
       description "Initial revision.";
       reference
         "RFC XXXX: I2NSF Capability YANG Data Model";

       // RFC Ed.: replace XXXX with an actual RFC number and remove
       // this note.
     }

     /*
      * Identities
      */

     identity event {
       description
         "Base identity for I2NSF events.";
       reference
      "draft-ietf-i2nsf-nsf-monitoring-data-model-04:
         "draft-ietf-i2nsf-nsf-monitoring-data-model-09: I2NSF NSF
          Monitoring YANG Data Model - Event";

    // RFC Ed.: replace the above draft with an actual RFC in the
    // YANG module and remove this note.
     }

     identity system-event-capability system-event {
       base event;
       description
         "Identity for system event";
       reference
      "draft-ietf-i2nsf-nsf-monitoring-data-model-04:
         "draft-ietf-i2nsf-nsf-monitoring-data-model-09: I2NSF NSF
          Monitoring YANG Data Model - System event";
     }

     identity system-alarm-capability system-alarm {
       base event;
       description
         "Identity for system alarm";
       reference
      "draft-ietf-i2nsf-nsf-monitoring-data-model-04:
         "draft-ietf-i2nsf-nsf-monitoring-data-model-09: I2NSF NSF
          Monitoring YANG Data Model - System alarm";
     }

     identity time {
       base event;
       description
         "Identity for time capabilities";
     }
     identity access-violation {
       base system-event-capability; system-event;
       description
         "Identity for access violation event";
       reference
      "draft-ietf-i2nsf-nsf-monitoring-data-model-04:
         "draft-ietf-i2nsf-nsf-monitoring-data-model-09: I2NSF NSF
          Monitoring YANG Data Model - System event for access
          violation";
     }

     identity configuration-change {
       base system-event-capability; system-event;
       description
         "Identity for configuration change event";
       reference
      "draft-ietf-i2nsf-nsf-monitoring-data-model-04:
         "draft-ietf-i2nsf-nsf-monitoring-data-model-09: I2NSF NSF
          Monitoring YANG Data Model - System event for configuration
          change";
     }

     identity memory-alarm {
       base system-alarm-capability; system-alarm;
       description
         "Identity for memory alarm. Alarm when memory usage
         exceeds a threshold.";
       reference
      "draft-ietf-i2nsf-nsf-monitoring-data-model-04:
         "draft-ietf-i2nsf-nsf-monitoring-data-model-09: I2NSF NSF
          Monitoring YANG Data Model - System alarm for memory";
     }

     identity cpu-alarm {
       base system-alarm-capability; system-alarm;
       description
         "Identity for CPU alarm. Alarm when CPU usage
         exceeds a threshold.";
       reference
      "draft-ietf-i2nsf-nsf-monitoring-data-model-04:
         "draft-ietf-i2nsf-nsf-monitoring-data-model-09: I2NSF NSF
          Monitoring YANG Data Model - System alarm for CPU";
     }

     identity disk-alarm {
       base system-alarm-capability; system-alarm;
       description
         "Identity for disk alarm. Alarm when disk usage
         exceeds a threshold.";
       reference
      "draft-ietf-i2nsf-nsf-monitoring-data-model-04:
         "draft-ietf-i2nsf-nsf-monitoring-data-model-09: I2NSF NSF
          Monitoring YANG Data Model - System alarm for disk";

     }

     identity hardware-alarm {
       base system-alarm-capability; system-alarm;
       description
         "Identity for hardware alarm. Alarm when a hardware failure
         or hardware degradation occurs.";
       reference
      "draft-ietf-i2nsf-nsf-monitoring-data-model-04:
         "draft-ietf-i2nsf-nsf-monitoring-data-model-09: I2NSF NSF
          Monitoring YANG Data Model - System alarm for hardware";
     }

     identity interface-alarm {
       base system-alarm-capability; system-alarm;
       description
         "Identity for interface alarm. Alarm when interface usage
         exceeds a threshold.";
       reference
      "draft-ietf-i2nsf-nsf-monitoring-data-model-04:
         "draft-ietf-i2nsf-nsf-monitoring-data-model-09: I2NSF NSF
          Monitoring YANG Data Model - System alarm for interface";
     }

     identity condition absolute-time {
       base time;
       description
      "Base identity for I2NSF conditions";
         "absolute time capabilities.
          If a network security function has the absolute time
          capability, the network security function supports
          rule execution according to absolute time.";
     }

     identity context-capability periodic-time {
       base condition; time;
       description
      "Base
         "periodic time capabilities.
          If a network security function has the periodic time
          capability, the network security function supports
          rule execution according to periodic time.";
     }

     identity target-device {
       description
         "Identity for context target condition capabilities for an NSF. capability. The context contains background information of various
       entities capability for
          matching the target device type.";
     }

     identity computer {
       base target-device;
       description
         "Identity for computer such as an access control list, application layer
       filter, target, user, group, personal computer (PC)
          and geography."; server";
     }

     identity access-control-list mobile-phone {
       base context-capability; target-device;
       description
         "Identity for Access Control List (ACL) condition capability";
    reference
      "RFC 8519: YANG Data Model mobile-phone such as smartphone and
          cellphone";
     }

     identity voip-volte-phone {
       base target-device;
       description
         "Identity for Network Access Control Lists
       (ACLs) - A user-ordered set of rules used to configure the
       forwarding behavior in an NSF."; voip-volte-phone";
     }

     identity application-layer-filter tablet {
       base context-capability; target-device;
       description
         "Identity for application-layer-filter condition capability.
       application-layer-filter capability can examine the contents
       of a packet (e.g., a URL contained in an HTTP message).";
    reference
      "RFC7230: Hypertext Transfer Protocol (HTTP/1.1): Message
       Syntax and Routing
       RFC7231: Hypertext Transfer Protocol (HTTP/1.1): Semantics tablet";
     }

     identity network-infrastructure-device {
       base target-device;
       description
         "Identity for network infrastructure devices
          such as switch, router, and Content"; access point";
     }

     identity target iot {
       base context-capability; target-device;
       description
         "Identity for target condition capability";
    reference
      "RFC 8519: YANG Data Model IoT (Internet of Things)";
     }

     identity ot {
       base target-device;
       description
         "Identity for Network Access Control Lists
       (ACLs) - An access control Operational Technology";
     }

     identity vehicle {
       base target-device;
       description
         "Identity for a target (e.g., vehicle that connects to and shares
          data through the Internet";

     }

     identity user-condition {
       description
         "Base identity for user condition capability. This is the
          capability of mapping user(s) into their corresponding IP address) in an NSF.";
          address";
     }

     identity user {
       base context-capability; user-condition;
       description
         "Identity for user condition capability.
          A user (e.g., employee) can be mapped to an IP address of
          a computing device (e.g., computer, laptop, and virtual
          machine) which the user is using.";
    reference
      "RFC 8519: YANG Data Model for Network Access Control Lists
       (ACLs) - An access control for a user (e.g., the
       corresponding IP address) in an NSF.";
     }

     identity group {
       base context-capability; user-condition;
       description
         "Identity for group condition capability.
          A group (e.g., employees) can be mapped to multiple IP
          addresses of computing devices (e.g., computers, laptops,
          and virtual machines) which the group is using.";
     }

     identity geography-location {
       description
         "Identity for geography condition capability";
       reference
         "RFC 8519: YANG Data Model 8805: A Format for Network Access Control Lists
       (ACLs) Self-Published IP Geolocation Feeds -
          An access control for a group (e.g., geographical location (i.e.,
          geolocation) that has the corresponding IP addresses) in an NSF."; prefix.";
     }

     identity source-location {
       base geography-location;
       description
         "Identity for source geography location condition capability";
       reference
         "RFC 8805: A Format for Self-Published IP Geolocation Feeds -
          An access control for a geographical location (i.e.,
          geolocation) that has the corresponding IP prefix.";
     }

     identity destination-location {
       base context-capability; geography-location;
       description
         "Identity for destination geography location condition
          capability";
       reference
         "RFC 8805: A Format for Self-Published IP Geolocation Feeds -
          An access control for a geographical location (i.e.,
          geolocation) that has the corresponding IP prefix.";
     }

     identity directional-capability directional {
       description
         "Base identity for directional traffic flow capability";
       reference
         "RFC 5101: Specification of the IP Flow Information
          Export (IPFIX) Protocol for the Exchange of IP
          Traffic Flow Information - Terminology Unidirectional
          and Bidirectional Flow";
     }

     identity unidirectional {
       base directional-capability; directional;
       description
         "Identity for unirectional traffic flow.";
       reference
         "RFC 5101: Specification of the IP Flow Information
          Export (IPFIX) Protocol for the Exchange of IP
          Traffic Flow Information - Terminology Unidirectional
          Flow";
     }

     identity bidirectional {
       base directional-capability; directional;
       description
         "Identity for bidirectional traffic flow.";
       reference
         "RFC 5101: Specification of the IP Flow Information
          Export (IPFIX) Protocol for the Exchange of IP
          Traffic Flow Information - Terminology Bidirectional
          Flow";
     }

     identity ipv4-capability protocol {
       description
         "Base identity for Internet Protocols";
     }

     identity ethernet {
       base condition; protocol;
       description
         "Base identity for IPv4 data link layer protocol.";
     }

     identity source-mac-address {
       base ethernet;
       description
         "Identity for the capability of matching Media Access Control
          (MAC) source address(es) condition capability"; capability.";
       reference
      "RFC 791: Internet Protocol";
         "IEEE 802.3: IEEE Standard for Ethernet";
     }

     identity destination-mac-address {
       base ethernet;
       description
         "Identity for the capability of matching Media Access Control
          (MAC) destination address(es) condition capability.";
       reference
         "IEEE 802.3: IEEE Standard for Ethernet";
     }

     identity exact-ipv4-header-length ether-type {
       base ipv4-capability; ethernet;
       description
         "Identity for exact-match the capability of matching the EtherType of a
          packet.";
       reference
         "IEEE 802.3: IEEE Standard for Ethernet";
     }

     identity ip {
       base protocol;
       description
         "Base identity for internet/network layer protocol,
          e.g., IPv4, IPv6, and ICMP.";
     }

     identity ipv4 {
       base ip;
       description
         "Base identity for IPv4 header-length condition capability";
       reference
         "RFC 791: Internet Protocol - Header Length"; Protocol";
     }

     identity range-ipv4-header-length ipv6 {
       base ipv4-capability; ip;
       description
      "Identity
         "Base identity for range-match IPv4 header-length IPv6 condition capability"; capabilities";
       reference
         "RFC 791: 8200: Internet Protocol - Header Length"; Protocol, Version 6 (IPv6)
          Specification";
     }

     identity ipv4-tos-dscp dscp {
       base ipv4-capability; ipv4;
       base ipv6;
       description
         "Identity for the capability of matching IPv4 Type-Of-Service (TOS) annd IPv6
          Differentiated Services Codepoint (DSCP)
       condition capability"; condition";
       reference
         "RFC 791: Internet Protocol - Type of Service
          RFC 2474: Definition of the Differentiated
          Services Field (DS Field) in the IPv4 and
          IPv6 Headers";
  }
  identity exact-ipv4-total-length {
    base ipv4-capability;
    description
      "Identity for exact-match IPv4 total length
      condition capability";
    reference
      "RFC 791: Headers
          RFC 8200: Internet Protocol Protocol, Version 6 (IPv6)
          Specification - Total Length"; Traffic Class";
     }

     identity range-ipv4-total-length length {
       base ipv4-capability; ipv4;
       base ipv6;
       description
         "Identity for range-match the capability of matching IPv4 total length
      condition capability"; Total Length header
          field or IPv6 Payload Length header field.

          IPv4 Total Length is the length of datagram, measured in octets,
          including internet header and data.

          IPv6 Payload Length is the length of the IPv6 payload, i.e., the
          rest of the packet following the IPv6 header, measured in
          octets.";
       reference
         "RFC 791: Internet Protocol - Total Length
          RFC 8200: Internet Protocol, Version 6 (IPv6)
          Specification - Payload Length";
     }

     identity ipv4-id ttl {
       base ipv4-capability; ipv4;
       base ipv6;
       description
         "Identity for the capability of matching IPv4 identification condition capability.
       IPv4 ID field is used for fragmentation and reassembly."; Time-To-Live (TTL)
          or IPv6 Hop Limit.";

       reference
         "RFC 791: Internet Protocol - Identification Time To Live (TTL)
          RFC 6864: Updated 8200: Internet Protocol, Version 6 (IPv6)
          Specification of the IPv4 ID Field -
       Fragmentation and Reassembly"; Hop Limit";
     }

     identity ipv4-fragment-flags next-header {
       base ipv4-capability; ipv4;
       base ipv6;
       description
         "Identity for the capability of matching IPv4 fragment flags condition capability"; Protocol Field or
          equivalent to IPv6 Next Header.";
       reference
      "RFC
         "IANA Website: Assigned Internet Protocol Numbers
          - Protocol Number for IPv4
          RFC 791: Internet Protocol - Fragmentation Flags"; Protocol
          RFC 8200: Internet Protocol, Version 6 (IPv6)
          Specification - Next Header";
     }

     identity exact-ipv4-fragment-offset source-address {
       base ipv4-capability; ipv4;
       base ipv6;
       description
         "Identity for exact-match the capability of matching IPv4 fragment offset or IPv6 source
          address(es) condition capability"; capability.";
       reference
         "RFC 791: Internet Protocol - Fragmentation Offset"; Address
          RFC 8200: Internet Protocol, Version 6 (IPv6)
          Specification - Source Address";
     }

     identity range-ipv4-fragment-offset destination-address {
       base ipv4-capability; ipv4;
       base ipv6;
       description
         "Identity for range-match the capability of matching IPv4 fragment offset or IPv6 destination
          address(es) condition capability"; capability.";
       reference
         "RFC 791: Internet Protocol - Fragmentation Offset"; Address
          RFC 8200: Internet Protocol, Version 6 (IPv6)
          Specification - Destination Address";
     }

     identity exact-ipv4-ttl flow-direction {
       base ipv4-capability; ipv4;
       base ipv6;
       description
         "Identity for exact-match IPv4 Time-To-Live (TTL) flow direction of matching IPv4/IPv6 source
          or destination address(es) condition capability"; capability where a flow's
          direction is either unidirectional or bidirectional";
       reference
         "RFC 791: Internet Protocol - Time To Live (TTL)";
          RFC 8200: Internet Protocol, Version 6 (IPv6)
          Specification";
     }

     identity range-ipv4-ttl header-length {
       base ipv4-capability; ipv4;
       description
         "Identity for range-match matching IPv4 Time-To-Live (TTL) header-length
         condition capability";
       reference
         "RFC 791: Internet Protocol - Time To Live (TTL)"; Header Length";
     }

     identity ipv4-protocol identification {
       base ipv4-capability; ipv4;
       description
         "Identity for IPv4 protocol identification condition capability"; capability.
          IPv4 ID field is used for fragmentation and reassembly.";
       reference
      "IANA Website: Assigned
         "RFC 791: Internet Protocol Numbers - Protocol Number for IPv4 Identification
          RFC 791: Internet Protocol - Protocol";
  }

  identity prefix-ipv4-address-flow-direction {
    base ipv4-capability;
    description
      "Identity for flow direction 6864: Updated Specification of prefix-match the IPv4 source
       or destination address(es) condition capability where flow
       direction is either unidirectional or bidirectional";
    reference
      "RFC 4340: Datagram Congestion Control Protocol"; ID Field -
          Fragmentation and Reassembly";
     }

     identity prefix-ipv4-address fragment-flags {
       base ipv4-capability; ipv4;
       description
         "Identity for prefix-match IPv4 source or destination
       address fragment flags condition capability. The addresses are specified
       by a pair of prefix and prefix length."; capability";
       reference
         "RFC 791: Internet Protocol - Address"; Fragmentation Flags";
     }

     identity prefix-ipv4-src-address fragment-offset {
       base ipv4-capability; ipv4;
       description
         "Identity for prefix-match matching IPv4 source address fragment offset
         condition
       capability. The addresses are specified by a pair of
       prefix and prefix length."; capability";
       reference
         "RFC 791: Internet Protocol - Address"; Fragmentation Offset";
     }

     identity prefix-ipv4-dst-address ipv4-options {
       base ipv4-capability; ipv4;
       description
         "Identity for prefix-match IPv4 destination address options condition capability. The addresses are specified by a
       pair of prefix and prefix length."; capability";
       reference
         "RFC 791: Internet Protocol - Address"; Options";
     }

     identity range-ipv4-address-flow-direction flow-label {
       base ipv4-capability; ipv6;
       description
         "Identity for matching IPv6 flow direction of range-match IPv4 source
       or destination address(es) label
         condition capability where flow
       direction is either unidirectional or bidirectional"; capability";
       reference
         "RFC 4340: Datagram Congestion Control Protocol"; 8200: Internet Protocol, Version 6 (IPv6)
          Specification - Flow Label
          RFC 6437: IPv6 Flow Label Specification";
     }

     identity range-ipv4-address header-order {
       base ipv4-capability; ipv6;
       description
         "Identity for range-match IPv4 source or destination
       address IPv6 extension header order condition capability. The addresses are specified
       by a pair of a start address and an end address.";
         capability";
       reference
         "RFC 791: 8200: Internet Protocol Protocol, Version 6 (IPv6)
          Specification - Address"; Extension Header Order";
     }

     identity range-ipv4-src-address hop-by-hop {
       base ipv4-capability; ipv6;
       description
         "Identity for range-match IPv4 source address condition
       capability. The addresses are specified by a pair of IPv6 hop by a start address and an end address."; hop options header
         condition capability";
       reference
         "RFC 791: 8200: Internet Protocol Protocol, Version 6 (IPv6)

         Specification - Address"; Options";
     }

     identity range-ipv4-dst-address routing-header {
       base ipv4-capability; ipv6;
       description
         "Identity for range-match IPv4 destination address IPv6 routing header condition capability. The addresses are specified by
       a pair of by a start address and an end address.";
         capability";
       reference
         "RFC 791: 8200: Internet Protocol Protocol, Version 6 (IPv6)
         Specification - Address"; Routing Header";
     }
     identity ipv4-ip-opts fragment-header {
       base ipv4-capability; ipv6;
       description
         "Identity for IPv4 option IPv6 fragment header condition
         capability";
       reference
         "RFC 791: Internet Protocol - Options";
  }

  identity ipv4-geo-ip {
    base ipv4-capability;
    description
      "Identity for IPv4 geography condition capability";
    reference
      "RFC 8805: Self-published IP Geolocation Data - An
       access control for a geographical location i.e.,
       geolocation (e.g., the corresponding IP address).";
  }

  identity ipv6-capability {
    base condition;
    description
      "Base identity for IPv6 condition capabilities";
    reference
      "RFC 8200: 8200: Internet Protocol, Version 6 (IPv6)
      Specification";
         Specification - Fragment Header";
     }

     identity ipv6-traffic-class-dscp destination-options {
       base ipv6-capability; ipv6;
       description
         "Identity for IPv6 traffic classes
      Differentiated Services Codepoint (DSCP) destination options condition
         capability";
       reference
         "RFC 8200: Internet Protocol, Version 6 (IPv6)
         Specification - Traffic Class
      RFC 2474: Definition of the Differentiated
      Services Field (DS Field) in the IPv4 and
      IPv6 Headers."; Destination Options";
     }

     identity exact-ipv6-flow-label icmp {
       base ipv6-capability; protocol;
       description
      "Identity
         "Base identity for exact-match IPv6 flow label ICMPv4 and ICMPv6 condition capability";
       reference
         "RFC 8200: 792: Internet Protocol, Control Message Protocol
          RFC 4443: Internet Control Message Protocol (ICMPv6)
          for the Internet Protocol Version 6 (IPv6) Specification
          - Flow Label
      RFC 6437: IPv6 Flow Label Specification"; ICMPv6";
     }

     identity range-ipv6-flow-label icmpv4 {
       base ipv6-capability; icmp;
       description
      "Identity
         "Base identity for range-match IPv6 flow label ICMPv4 condition capability";
       reference
         "RFC 8200: 792: Internet Protocol, Version 6 (IPv6)
      Specification - Flow Label
      RFC 6437: IPv6 Flow Label Specification"; Control Message Protocol";
     }

     identity exact-ipv6-payload-length icmpv6 {
       base ipv6-capability; icmp;
       description
      "Identity
         "Base identity for exact-match IPv6 payload length ICMPv6 condition capability";
       reference
         "RFC 8200: 4443: Internet Protocol, Control Message Protocol (ICMPv6)
          for the Internet Protocol Version 6 (IPv6) Specification
          - Payload Length"; ICMPv6";
     }
     identity range-ipv6-payload-length type {
       base ipv6-capability; icmpv4;
       base icmpv6;
       description
         "Identity for range-match IPv6 payload length ICMPv4 and ICMPv6 type condition capability";
       reference
         "RFC 8200: 792: Internet Protocol, Control Message Protocol
          RFC 4443: Internet Control Message Protocol (ICMPv6)
          for the Internet Protocol Version 6 (IPv6) Specification
          - Payload Length"; ICMPv6";
     }

     identity ipv6-next-header code {
       base ipv6-capability; icmpv4;
       base icmpv6;
       description
         "Identity for IPv6 next header ICMPv4 and ICMPv6 code condition capability";
       reference
      "IANA Website: Assigned
         "RFC 792: Internet Control Message Protocol Numbers
       -
          RFC 4443: Internet Control Message Protocol Number (ICMPv6)
          for IPv6
       RFC 8200: the Internet Protocol, Protocol Version 6 (IPv6) Specification
          - Next Header"; ICMPv6";
     }

     identity exact-ipv6-hop-limit transport-protocol {
       base ipv6-capability; protocol;
       description
      "Identity
         "Base identity for exact-match IPv6 hop limit Layer 4 protocol condition
      capability";
    reference
      "RFC 8200: Internet Protocol, Version 6 (IPv6)
      Specification - Hop Limit"; capabilities, e.g.,
          TCP, UDP, SCTP, DCCP, and ICMP";
     }

     identity range-ipv6-hop-limit tcp {
       base ipv6-capability; transport-protocol;
       description
      "Identity
         "Base identity for range-match IPv6 hop limit TCP condition
      capability"; capabilities";
       reference
         "RFC 8200: Internet Protocol, Version 6 (IPv6)
      Specification - Hop Limit"; 793: Transmission Control Protocol
          draft-ietf-tcpm-rfc793bis: Transmission Control Protocol
          (TCP) Specification";
     }

     identity prefix-ipv6-address-flow-direction udp {
       base ipv6-capability; transport-protocol;
       description
      "Identity
         "Base identity for flow direction of prefix-match IPv6 source
       or destination address(es) UDP condition capability where flow
       direction is either unidirectional or bidirectional"; capabilities";
       reference
         "RFC 8200: Internet Protocol, Version 6 (IPv6)
       Specification - Address"; 768: User Datagram Protocol";
     }
     identity prefix-ipv6-address sctp {
       base ipv6-capability; transport-protocol;
       description
         "Identity for prefix-match IPv6 address SCTP condition
       capability. The addresses are specified by a pair
       of prefix and prefix length."; capabilities";
       reference
         "RFC 8200: Internet Protocol, Version 6 (IPv6)
       Specification - Address"; 4960: Stream Control Transmission Protocol";
     }

     identity prefix-ipv6-src-address dccp {
       base ipv6-capability; transport-protocol;
       description
         "Identity for prefix-match IPv6 source address DCCP condition
       capability. The addresses are specified by a pair of
       prefix and prefix length."; capabilities";
       reference
         "RFC 8200: Internet Protocol, Version 6 (IPv6)
       Specification - Address"; 4340: Datagram Congestion Control Protocol";
     }

     identity prefix-ipv6-dst-address source-port-number {
       base ipv6-capability; tcp;
       base udp;
       base sctp;
       base dccp;
       description
         "Identity for prefix-match IPv6 destination address
       condition capability. The addresses are specified by a
       pair of prefix matching TCP, UDP, SCTP, and prefix length."; DCCP source port
          number condition capability";
       reference
         "RFC 8200: Internet Protocol, Version 6 (IPv6)
       Specification 793: Transmission Control Protocol - Address"; Port Number
          draft-ietf-tcpm-rfc793bis: Transmission Control Protocol
          (TCP) Specification
          RFC 768: User Datagram Protocol
          RFC 4960: Stream Control Transmission Protocol
          RFC 4340: Datagram Congestion Control Protocol";
     }

     identity range-ipv6-address-flow-direction destination-port-number {
       base ipv6-capability; tcp;
       base udp;
       base sctp;
       base dccp;
       description
         "Identity for flow direction of prefix-match IPv6 source
       or matching TCP, UDP, SCTP, and DCCP destination address(es) port
          number condition capability where flow
       direction is either unidirectional or bidirectional"; capability";
       reference
         "RFC 8200: Internet Protocol, Version 6 (IPv6)
       Specification 793: Transmission Control Protocol - Address"; Port Number
          draft-ietf-tcpm-rfc793bis: Transmission Control Protocol
          (TCP) Specification";
     }

     identity range-ipv6-address flags {
       base ipv6-capability; tcp;
       description
         "Identity for range-match IPv6 source or destination
       address TCP control bits (flags) condition capability. capability";
       reference
         "RFC 793: Transmission Control Protocol - Flags
          RFC 3168: The addresses are
       specified by a pair Addition of a start address and an end
       address.";
    reference
      "RFC 8200: Internet Protocol, Version 6 (IPv6)
       Specification Explicit Congestion Notification
          (ECN) to IP - Address"; TCP Header Flags
          draft-ietf-tcpm-rfc793bis: Transmission Control Protocol
          (TCP) Specification
          draft-ietf-tcpm-accurate-ecn: More Accurate ECN Feedback
          in TCP";
     }

     identity range-ipv6-src-address tcp-options {
       base ipv6-capability; tcp;
       description
         "Identity for range-match IPv6 source address TCP options condition capability. The addresses are specified
       by a pair of a start address and an end address."; capability.";
       reference
         "RFC 8200: Internet Protocol, Version 6 (IPv6)
       Specification 793: Transmission Control Protocol - Address"; Options
          draft-ietf-tcpm-rfc793bis: Transmission Control Protocol
          (TCP) Specification
          RFC 6691: TCP Options and Maximum Segment Size
          RFC 7323: TCP Extensions for High Performance";
     }

     identity range-ipv6-dst-address total-length {
       base ipv6-capability; udp;
       description
         "Identity for range-match IPv6 destination address matching UDP total-length condition capability.
          The addresses are specified
       by a pair of a start address and an end address."; UDP total length can be smaller than the IP transport
          length for UDP transport layer options.";
       reference
         "RFC 8200: Internet Protocol, Version 6 (IPv6)
       Specification 768: User Datagram Protocol - Address"; Total Length
          draft-ietf-tsvwg-udp-options: Transport Options for UDP";
     }

     identity ipv6-header-order verification-tag {
       base ipv6-capability; sctp;
       description
         "Identity for IPv6 extension header order range-match SCTP verification tag condition
          capability";
       reference
         "RFC 8200: Internet Protocol, Version 6 (IPv6)
      Specification 4960: Stream Control Transmission Protocol - Extension Header Order"; Verification
          Tag";
     }

     identity ipv6-options chunk-type {
       base ipv6-capability; sctp;
       description
         "Identity for IPv6 options SCTP chunk type condition capability";
       reference
         "RFC 8200: Internet Protocol, Version 6 (IPv6)
      Specification 4960: Stream Control Transmission Protocol - Options"; Chunk Type";
     }

     identity ipv6-hop-by-hop service-code {
       base ipv6-capability; dccp;
       description
         "Identity for IPv6 hop by hop options header DCCP Service Code condition capability"; capabilitiy";
       reference
         "RFC 8200: 4340: Datagram Congestion Control Protocol
          RFC 5595: The Datagram Congestion Control Protocol (DCCP)
          Service Codes
          RFC 6335: Internet Protocol, Version 6 (IPv6)
      Specification Assigned Numbers Authority (IANA)
          Procedures for the Management of the Service Name and
          Transport Protocol Port Number Registry - Options"; Service Code";
     }

     identity ipv6-routing-header application-protocol {
       base ipv6-capability; protocol;
       description
      "Identity
         "Base identity for IPv6 routing header condition
      capability"; Application protocol";
     }

     identity http {
       base application-protocol;
       description
         "The identity for HTTP protocol.";
       reference
         "RFC 8200: Internet Protocol, Version 6 (IPv6)
      Specification - 2616: Hypertext Transfer Protocol (HTTP)
          RFC7230: Hypertext Transfer Protocol (HTTP/1.1): Message
          Syntax and Routing Header";
          RFC7231: Hypertext Transfer Protocol (HTTP/1.1): Semantics
          and Content";
     }

     identity ipv6-fragment-header https {
       base ipv6-capability; application-protocol;
       description
      "Identity
         "The identity for IPv6 fragment header condition
      capability"; HTTPS protocol.";
       reference
         "RFC 8200: Internet Protocol, Version 6 (IPv6)
      Specification - Fragment Header"; 2818: HTTP over TLS (HTTPS)
          RFC7230: Hypertext Transfer Protocol (HTTP/1.1): Message
          Syntax and Routing
          RFC7231: Hypertext Transfer Protocol (HTTP/1.1): Semantics
          and Content";
     }
     identity ipv6-destination-options ftp {
       base ipv6-capability; application-protocol;
       description
      "Identity
         "The identity for IPv6 destination options condition
      capability"; ftp protocol.";
       reference
         "RFC 8200: Internet Protocol, Version 6 (IPv6)
      Specification - Destination Options"; 959: File Transfer Protocol (FTP)";
     }

     identity ipv6-geo-ip ssh {
       base ipv6-capability; application-protocol;
       description
      "Identity
         "The identity for IPv4 geography condition capability"; ssh protocol.";
       reference
         "RFC 8805: Self-published IP Geolocation Data - An
       access control for a geographical location i.e.,
       geolocation (e.g., the corresponding IP address)."; 4250: The Secure Shell (SSH) Protocol";
     }

     identity tcp-capability telnet {
       base condition; application-protocol;
       description
      "Base
         "The identity for TCP condition capabilities"; telnet.";
       reference
         "RFC 793: Transmission Control Protocol
       draft-ietf-tcpm-rfc793bis: Transmission Control Protocol
       (TCP) Specification"; 854: Telnet Protocol";
     }

     identity exact-tcp-port-num-flow-direction smtp {
       base tcp-capability; application-protocol;
       description
      "Identity
         "The identity for flow direction of exact-match TCP source or
       destination port number condition capability where flow
       direction is either unidirectional or bidirectional"; smtp.";
       reference
         "RFC 793: Transmission Control Protocol - Port Number
       draft-ietf-tcpm-rfc793bis: Transmission Control 5321: Simple Mail Transfer Protocol
       (TCP) Specification"; (SMTP)";
     }

     identity exact-tcp-port-num sftp {
       base tcp-capability; application-protocol;
       description
      "Identity
         "The identity for exact-match TCP source or destination port
       number condition capability"; sftp.";
       reference
         "RFC 793: Transmission Control Protocol - Port Number
       draft-ietf-tcpm-rfc793bis: Transmission Control 913: Simple File Transfer Protocol
       (TCP) Specification"; (SFTP)";
     }

     identity exact-tcp-src-port-num pop3 {
       base tcp-capability; application-protocol;
       description
      "Identity
         "The identity for exact-match TCP source port
       number condition capability"; pop3.";
       reference
         "RFC 793: Transmission Control 1081: Post Office Protocol - Port Number
       draft-ietf-tcpm-rfc793bis: Transmission Control Protocol
       (TCP) Specification"; Version 3 (POP3)";
     }
     identity exact-tcp-dst-port-num imap {
       base tcp-capability; application-protocol;
       description
      "Identity
         "The identity for exact-match TCP destination port
       number condition capability"; Internet Message Access Protocol (IMAP).";
       reference
         "RFC 793: Transmission Control Protocol 3501: INTERNET MESSAGE ACCESS PROTOCOL - Port Number
       draft-ietf-tcpm-rfc793bis: Transmission Control Protocol
       (TCP) Specification"; VERSION 4rev1";
     }

     identity range-tcp-port-num-flow-direction action {
    base tcp-capability;
       description
      "Identity
         "Base identity for flow direction of range-match TCP source or
       destination port number condition capability where flow
       direction is either unidirectional or bidirectional";
    reference
      "RFC 793: Transmission Control Protocol - Port Number
       draft-ietf-tcpm-rfc793bis: Transmission Control Protocol
       (TCP) Specification";
  }

  identity range-tcp-port-num {
    base tcp-capability;
    description
      "Identity for range-match TCP source or destination port
       number condition capability. The port numbers are
       specified by a pair of a start port number and an end
       port number.";

    reference
      "RFC 793: Transmission Control Protocol - Port Number
       draft-ietf-tcpm-rfc793bis: Transmission Control Protocol
       (TCP) Specification";
  }

  identity range-tcp-src-port-num {
    base tcp-capability;
    description
      "Identity for range-match TCP source port number
       condition capability. The port numbers are specified by
       a pair of a start port number and an end port number.";
    reference
      "RFC 793: Transmission Control Protocol - Port Number
       draft-ietf-tcpm-rfc793bis: Transmission Control Protocol
       (TCP) Specification";
  }
  identity range-tcp-dst-port-num {
    base tcp-capability;
    description
      "Identity for range-match TCP destination port number
       condition capability. The port numbers are specified by
       a pair of a start port number and an end port number.";
    reference
      "RFC 793: Transmission Control Protocol - Port Number
       draft-ietf-tcpm-rfc793bis: Transmission Control Protocol
       (TCP) Specification";
  }

  identity tcp-flags {
    base tcp-capability;
    description
      "Identity for TCP control bits (flags) condition capability";
    reference
      "RFC 793: Transmission Control Protocol - Flags
       RFC 3168: The Addition of Explicit Congestion Notification
       (ECN) to IP - TCP Header Flags
       draft-ietf-tcpm-rfc793bis: Transmission Control Protocol
       (TCP) Specification
       draft-ietf-tcpm-accurate-ecn: More Accurate ECN Feedback
       in TCP";
  }

  identity tcp-options {
    base tcp-capability;
    description
      "Identity for TCP options condition capability";
    reference
      "RFC 793: Transmission Control Protocol - Options
       draft-ietf-tcpm-rfc793bis: Transmission Control Protocol
       (TCP) Specification
       RFC 6691: TCP Options and Maximum Segment Size
       RFC 7323: TCP Extensions for High Performance";
  }

  identity udp-capability {
    base condition;
    description
      "Base identity for UDP condition capabilities";
    reference
      "RFC 768: User Datagram Protocol";
  }

  identity exact-udp-port-num-flow-direction {
    base udp-capability;
    description
      "Identity for flow direction of exact-match UDP source or
       destination port number condition capability where flow
       direction is either unidirectional or bidirectional";
    reference
      "RFC 768: User Datagram Protocol - Port Number";
  }

  identity exact-udp-port-num {
    base udp-capability;
    description
      "Identity for exact-match UDP source or destination
       port number condition capability";
    reference
      "RFC 768: User Datagram Protocol - Port Number";
  }

  identity exact-udp-src-port-num {
    base udp-capability;
    description
      "Identity for exact-match UDP source port number
       condition capability";
    reference
      "RFC 768: User Datagram Protocol - Port Number";
  }

  identity exact-udp-dst-port-num {
    base udp-capability;
    description
      "Identity for exact-match UDP destination port number
       condition capability";
    reference
      "RFC 768: User Datagram Protocol - Port Number";
  }

  identity range-udp-port-num-flow-direction {
    base udp-capability;
    description
      "Identity for flow direction of range-match UDP source or
       destination port number condition capability where flow
       direction is either unidirectional or bidirectional";
    reference
      "RFC 768: User Datagram Protocol - Port Number";
  }

  identity range-udp-port-num {
    base udp-capability;
    description
      "Identity for range-match UDP source or destination
       port number condition capability. The port numbers
       are specified by a pair of a start port number and
       an end port number.";
    reference
      "RFC 768: User Datagram Protocol - Port Number";
  }

  identity range-udp-src-port-num {
    base udp-capability;
    description
      "Identity for range-match UDP source port number
       condition capability. The port numbers are specified by
       a pair of a start port number and an end port number.";
    reference
      "RFC 768: User Datagram Protocol - Port Number";
  }

  identity range-udp-dst-port-num {
    base udp-capability;
    description
      "Identity for range-match TCP destination port number
       condition capability. The port numbers are specified by
       a pair of a start port number and an end port number.";
    reference
      "RFC 768: User Datagram Protocol - Port Number";
  }

  identity exact-udp-total-length {
    base udp-capability;
    description
      "Identity for exact-match UDP total-length condition capability.
       The UDP total length can be smaller than the IP transport
       length for UDP transport layer options.";
    reference
      "RFC 768: User Datagram Protocol - Total Length
       draft-ietf-tsvwg-udp-options: Transport Options for UDP";
  }

  identity range-udp-total-length {
    base udp-capability;
    description
      "Identity for range-match UDP total-length condition capability.
       The UDP total length can be smaller than the IP transport
       length for UDP transport layer options.";
    reference
      "RFC 768: User Datagram Protocol - Total Length
       draft-ietf-tsvwg-udp-options: Transport Options for UDP";

  }

  identity sctp-capability {
   description
      "Identity for SCTP condition capabilities";
    reference
      "RFC 4960: Stream Control Transmission Protocol";
  }

  identity exact-sctp-port-num-flow-direction {
    base sctp-capability;
    description
      "Identity for flow direction of range-match SCTP source or
       destination port number condition capability where flow
       direction is either unidirectional or bidirectional";
    reference
      "RFC 4960: Stream Control Transmission Protocol - Port Number";
  }

  identity exact-sctp-port-num {
    base sctp-capability;
    description
      "Identity for exact-match SCTP source or destination
       port number condition capability";
    reference
      "RFC 4960: Stream Control Transmission Protocol - Port Number";
  }

  identity exact-sctp-src-port-num {
    base sctp-capability;
    description
      "Identity for exact-match SCTP source port number
       condition capability";
    reference
      "RFC 4960: Stream Control Transmission Protocol - Port Number";
  }

  identity exact-sctp-dst-port-num {
    base sctp-capability;
    description
      "Identity for exact-match SCTP destination port number
       condition capability";
    reference
      "RFC 4960: Stream Control Transmission Protocol - Port Number";
  }

  identity range-sctp-port-num-flow-direction {
    base sctp-capability;
    description
      "Identity for flow direction of range-match SCTP source or
       destination port number condition capability where flow
       direction is either unidirectional or bidirectional";
    reference
      "RFC 4960: Stream Control Transmission Protocol - Port Number";
  }

  identity range-sctp-port-num {
    base sctp-capability;
    description
      "Identity for range-match SCTP source or destination
       port number condition capability. The port numbers are
       specified by a pair of a start port number and an end
       port number.";
    reference
      "RFC 4960: Stream Control Transmission Protocol - Port Number";
  }

  identity range-sctp-src-port-num {
    base sctp-capability;
    description
      "Identity for range-match SCTP source port number
       condition capability. The port numbers are specified by
       a pair of a start port number and an end port number.";
    reference
      "RFC 4960: Stream Control Transmission Protocol - Port Number";
  }

  identity range-sctp-dst-port-num {
    base sctp-capability;
    description
      "Identity for range-match SCTP destination port number
       condition capability. The port numbers are specified by
       a pair of a start port number and an end port number.";
    reference
      "RFC 4960: Stream Control Transmission Protocol - Port Number";
  }

  identity sctp-verification-tag {
    base sctp-capability;
    description
      "Identity for range-match SCTP verification tag condition
       capability";
    reference
      "RFC 4960: Stream Control Transmission Protocol - Verification Tag";
  }
  identity sctp-chunk-type {
    base sctp-capability;
    description
      "Identity for SCTP chunk type condition capability";
    reference
      "RFC 4960: Stream Control Transmission Protocol - Chunk Type";
  }

  identity dccp-capability {
   description
      "Identity for DCCP condition capabilities";
    reference
      "RFC 4340: Datagram Congestion Control Protocol";
  }

  identity exact-dccp-port-num-flow-direction {
    base dccp-capability;
    description
      "Identity for flow direction of exact-match DCCP source or
       destination port number condition capability where flow
       direction is either unidirectional or bidirectional";
    reference
      "RFC 4340: Datagram Congestion Control Protocol";
  }

  identity exact-dccp-port-num {
    base dccp-capability;
    description
      "Identity for exact-match DCCP source or destination
       port number condition capability";
    reference
      "RFC 4340: Datagram Congestion Control Protocol";
  }

  identity exact-dccp-src-port-num {
    base dccp-capability;
    description
      "Identity for exact-match DCCP source port number
       condition capability";
    reference
      "RFC 4340: Datagram Congestion Control Protocol";
  }

  identity exact-dccp-dst-port-num {
    base dccp-capability;
    description
      "Identity for exact-match DCCP destination port number
       condition capability";

    reference
      "RFC 4340: Datagram Congestion Control Protocol";
  }

  identity range-dccp-port-num-flow-direction {
    base dccp-capability;
    description
      "Identity for flow direction of range-match DCCP source or
       destination port number condition capability where flow
       direction is either unidirectional or bidirectional";
    reference
      "RFC 4340: Datagram Congestion Control Protocol";
  }

  identity range-dccp-port-num {
    base dccp-capability;
    description
      "Identity for range-match DCCP source or destination
       port number condition capability. The port numbers are
       specified by a pair of a start port number and an end
       port number.";
    reference
      "RFC 4340: Datagram Congestion Control Protocol";
  }

  identity range-dccp-src-port-num {
    base dccp-capability;
    description
      "Identity for range-match DCCP source port number
       condition capability. The port numbers are specified by
       a pair of a start port number and an end port number.";
    reference
      "RFC 4340: Datagram Congestion Control Protocol";
  }

  identity range-dccp-dst-port-num {
    base dccp-capability;
    description
      "Identity for range-match DCCP source port number
       condition capability. The port numbers are specified by
       a pair of a start port number and an end port number.";
    reference
      "RFC 4340: Datagram Congestion Control Protocol";
  }

  identity dccp-service-code {
    base dccp-capability;
    description
      "Identity for DCCP Service Code condition capabilitiy";
    reference
      "RFC 4340: Datagram Congestion Control Protocol
       RFC 5595: The Datagram Congestion Control Protocol (DCCP)
       Service Codes
       RFC 6335: Internet Assigned Numbers Authority (IANA)
       Procedures for the Management of the Service Name and
       Transport Protocol Port Number Registry - Service Code";
  }

  identity icmp-capability {
    base condition;
    description
      "Base identity for ICMP condition capability";
    reference
      "RFC 792: Internet Control Message Protocol";
  }

  identity icmp-type {
    base icmp-capability;
    description
      "Identity for ICMP type condition capability";
    reference
      "RFC 792: Internet Control Message Protocol";
  }

  identity icmp-code {
    base icmp-capability;
    description
      "Identity for ICMP code condition capability";
    reference
      "RFC 792: Internet Control Message Protocol";
  }

  identity icmpv6-capability {
    base condition;
    description
      "Base identity for ICMPv6 condition capability";
    reference
      "RFC 4443: Internet Control Message Protocol (ICMPv6)
       for the Internet Protocol Version 6 (IPv6) Specification
       - ICMPv6";
  }

  identity icmpv6-type {
    base icmpv6-capability;
    description
      "Identity for ICMPv6 type condition capability";

    reference
      "RFC 4443: Internet Control Message Protocol (ICMPv6)
       for the Internet Protocol Version 6 (IPv6) Specification
       - ICMPv6";
  }

  identity icmpv6-code {
    base icmpv6-capability;
    description
      "Identity for ICMPv6 code condition capability";
    reference
      "RFC 4443: Internet Control Message Protocol (ICMPv6)
       for the Internet Protocol Version 6 (IPv6) Specification
       - ICMPv6";
  }

  identity url-capability {
    base condition;
    description
      "Base identity for URL condition capability";
  }

  identity pre-defined {
    base url-capability;
    description
      "Identity for pre-defined URL Database condition capability.
       where URL database is a public database for URL filtering.";
  }

  identity user-defined {
    base url-capability;
    description
      "Identity for user-defined URL Database condition capability.
       that allows a users manual addition of URLs for URL
       filtering.";
  }

  identity log-action-capability {
    description
      "Base identity for log-action capability";
  }

  identity rule-log {
    base log-action-capability;
    description
      "Identity for rule log log-action capability.
       Log the received packet based on the rule";
  }
  identity session-log {
    base log-action-capability;
    description
      "Identity for session log log-action capability.
       Log the received packet based on the session.";
  }

  identity ingress-action-capability {
    description
      "Base identity for ingress-action capability";
    reference
      "RFC 8329: Framework for Interface to Network Security
       Functions - Ingress action";
  }

  identity egress-action-capability {
    description
      "Base identity for egress-action capability";
    reference
      "RFC 8329: Framework for Interface to Network Security
       Functions - Egress action";
  }

  identity default-action-capability {
    description
      "Base identity for default-action capability";
  }

  identity pass {
    base ingress-action-capability;
    base egress-action-capability;
    base default-action-capability;
    description
      "Identity for pass action capability";
    reference
      "RFC 8329: Framework for Interface to Network Security
       Functions - Ingress, egress, and pass actions.";
  }

  identity drop {
    base ingress-action-capability;
    base egress-action-capability;
    base default-action-capability;
    description
      "Identity for drop action capability";
    reference
      "RFC 8329: Framework for Interface to Network Security
       Functions - Ingress, egress, and drop actions.";

  }

  identity alert {
    base ingress-action-capability;
    base egress-action-capability;
    base default-action-capability;
    description
      "Identity for alert action capability";
    reference
      "RFC 8329: Framework for Interface to Network Security
       Functions - Ingress, egress, and alert actions.
       draft-ietf-i2nsf-nsf-monitoring-data-model-04: I2NSF
       NSF Monitoring YANG Data Model - Alarm (i.e., alert).";
  }

  identity mirror {
    base ingress-action-capability;
    base egress-action-capability;
    base default-action-capability;
    description
      "Identity for mirror action capability";
    reference
      "RFC 8329: Framework for Interface to Network Security
       Functions - Ingress, egress, and mirror actions.";
  }

  identity invoke-signaling {
    base egress-action-capability;
    description
      "Identity for invoke signaling action capability";
    reference
      "RFC 8329: Framework for Interface to Network Security
       Functions - Invoke-signaling action";
  }

  identity forwarding {
    base egress-action-capability;
    description
      "Identity for forwarding action capability";
    reference
      "RFC 8329: Framework for Interface to Network Security
       Functions - Forwarding action";
  }

  identity redirection {
    base egress-action-capability;
    description
      "Identity for redirection action capability";

    reference
      "RFC 8329: Framework for Interface to Network Security
       Functions - Redirection action";
  }

  identity resolution-strategy-capability {
    description
      "Base identity for resolution strategy capability";
  }

  identity fmr {
    base resolution-strategy-capability;
    description
      "Identity for First Matching Rule (FMR) resolution
       strategy capability";
  }

  identity lmr {
    base resolution-strategy-capability;
    description
      "Identity for Last Matching Rule (LMR) resolution
       strategy capability";
  }

  identity pmr {
    base resolution-strategy-capability;
    description
      "Identity for Prioritized Matching Rule (PMR) resolution
       strategy capability";
  }

  identity pmre {
    base resolution-strategy-capability;
    description
      "Identity for Prioritized Matching Rule with Errors (PMRE)
       resolution strategy capability";
     }

     identity pmrn log-action {
       base resolution-strategy-capability;
    description
      "Identity for Prioritized Matching Rule with No Errors (PMRN)
       resolution strategy capability";
  }

  identity advanced-nsf-capability { action;
       description
         "Base identity for advanced Network Security Function (NSF)
       capability.  This can be used for advanced NSFs such as
       Anti-Virus, Anti-DDoS Attack, IPS, and VoIP/VoLTE Security
       Service.";
    reference
      "RFC 8329: Framework for Interface to Network Security
       Functions - Advanced NSF log-action capability";
     }

     identity anti-virus-capability ingress-action {
    base advanced-nsf-capability;
    description
      "Identity for advanced NSF Anti-Virus capability.
       This can be used for an extension point
       base action;
       description
         "Base identity for Anti-Virus
       as an advanced NSF."; ingress-action capability";
       reference
         "RFC 8329: Framework for Interface to Network Security
          Functions - Advanced NSF Anti-Virus capability"; Section 7.2";
     }

     identity anti-ddos-capability egress-action {
       base advanced-nsf-capability; action;
       description
      "Identity for advanced NSF Anti-DDoS Attack capability.
       This can be used for an extension point
         "Base identity for Anti-DDoS
       Attack as an advanced NSF."; egress-action capability";
       reference
         "RFC 8329: Framework for Interface to Network Security
          Functions - Advanced NSF Anti-DDoS Attack Section 7.2";
     }

     identity default-action {
       base action;
       description
         "Base identity for default-action capability";
     }

     identity ips-capability rule-log {
       base advanced-nsf-capability; log-action;
       description
         "Identity for advanced NSF IPS capabilities.  This can be
       used for an extension point rule log-action capability.
          Log the received packet based on the rule";

     }

     identity session-log {
       base log-action;
       description
         "Identity for IPS as an advanced NSF.";
    reference
      "RFC 8329: Framework session log-action capability.
          Log the received packet based on the session.";
     }

     identity pass {
       base ingress-action;
       base egress-action;
       base default-action;
       description
         "Identity for Interface pass action capability. The pass action allows
          packet or flow to Network Security
       Functions - Advanced go through the NSF IPS capability"; entering or exiting the
          internal network.";
     }

     identity voip-volte-capability drop {
       base advanced-nsf-capability; ingress-action;
       base egress-action;
       base default-action;
       description
         "Identity for advanced NSF VoIP/VoLTE Security Service drop action capability.  This can be used for an extension point The drop action denies
          packet to go through the NSF entering or exiting the internal
          network.";
     }

     identity mirror {
       base ingress-action;
       base egress-action;
       base default-action;
       description
         "Identity for VoIP/VoLTE Security Service as an advanced mirror action capability. The mirror action copies
          packet and send it to the monitoring entity while still allow
          the packet or flow to go through the NSF.";
    reference
      "RFC 3261: SIP: Session Initiation Protocol";
     }

     identity detect rate-limit {
       base anti-virus-capability; ingress-action;
       base egress-action;
       base default-action;
       description
         "Identity for advanced NSF Anti-Virus Detection rate limiting action capability.
       This The rate limit
          action limits the number of packets or flows that can be used for an extension point for Anti-Virus
       Detection as an advanced NSF.";
    reference
      "RFC 8329: Framework for Interface to Network Security
       Functions - Advanced go through
          the NSF Anti-Virus Detection by dropping packets or flows (randomly or
          systematically).";

     }

     identity invoke-signaling {
       base egress-action;
       description
         "Identity for invoke signaling action capability";
     }

     identity allow-list tunnel-encapsulation {
       base anti-virus-capability; egress-action;
       description
         "Identity for advanced NSF Anti-Virus Allow List capability.
       This can be used for an extension point for Anti-Virus
       Allow List as an advanced NSF.";
    reference
      "RFC 8329: Framework for Interface to Network Security
       Functions - Advanced NSF Anti-Virus Allow List tunnel encapsulation action capability";
     }

     identity syn-flood-action forwarding {
       base anti-ddos-capability; egress-action;
       description
         "Identity for advanced NSF Anti-DDoS SYN Flood Action
       capability.  This can be used for an extension point for
       Anti-DDoS SYN Flood Action as an advanced NSF.";
    reference
      "RFC 8329: Framework for Interface to Network Security
       Functions - Advanced NSF Anti-DDoS SYN Flood Action forwarding action capability";
     }

     identity udp-flood-action transformation {
       base anti-ddos-capability; egress-action;
       description
         "Identity for advanced NSF Anti-DDoS UDP Flood Action
       capability.  This can be used for an extension point for
       Anti-DDoS UDP Flood Action as an advanced NSF.";
    reference
      "RFC 8329: Framework transformation action capability";
     }

     identity resolution-strategy {
       description
         "Base identity for Interface to Network Security
       Functions - Advanced NSF Anti-DDoS UDP Flood Action resolution strategy capability";
     }

     identity http-flood-action fmr {
       base anti-ddos-capability; resolution-strategy;
       description
         "Identity for advanced NSF Anti-DDoS HTTP Flood Action
       capability.  This can be used for an extension point for
       Anti-DDoS HTTP Flood Action as an advanced NSF.";
    reference
      "RFC 8329: Framework for Interface to Network Security
       Functions - Advanced NSF Anti-DDoS HTTP Flood Action First Matching Rule (FMR) resolution
          strategy capability";
     }

     identity https-flood-action lmr {
       base anti-ddos-capability; resolution-strategy;
       description
         "Identity for advanced NSF Anti-DDoS HTTPS Flood Action
       capability.  This can be used for an extension point for
       Anti-DDoS HTTPS Flood Action as an advanced NSF.";
    reference
      "RFC 8329: Framework for Interface to Network Security
       Functions - Advanced NSF Anti-DDoS HTTPS Flood Action Last Matching Rule (LMR) resolution
          strategy capability";
     }

     identity dns-request-flood-action pmr {
       base anti-ddos-capability; resolution-strategy;
       description
         "Identity for advanced NSF Anti-DDoS DNS Request Flood
       Action capability.  This can be used for an extension
       point for Anti-DDoS DNS Request Flood Action as an
       advanced NSF.";
    reference
      "RFC 8329: Framework for Interface to Network Security
       Functions - Advanced NSF Anti-DDoS DNS Request Flood
       Action Prioritized Matching Rule (PMR) resolution
          strategy capability";
     }

     identity dns-reply-flood-action pmre {
       base anti-ddos-capability; resolution-strategy;
       description
         "Identity for advanced NSF Anti-DDoS DNS Reply Flood
       Action capability.  This can be used Prioritized Matching Rule with Errors (PMRE)
          resolution strategy capability";
     }

     identity pmrn {
       base resolution-strategy;
       description
         "Identity for an extension
       point Prioritized Matching Rule with No Errors (PMRN)
          resolution strategy capability";
     }

     identity advanced-nsf {
       description
         "Base identity for Anti-DDoS DNS Reply Flood Action as an advanced NSF.";
    reference
      "RFC 8329: Framework for Interface to Network Security
       Functions - Advanced NSF Anti-DDoS DNS Reply Flood
       Action capability"; Function (NSF)
          capability.";
     }

     identity icmp-flood-action content-security-control {
       base anti-ddos-capability; advanced-nsf;
       description
      "Identity for advanced NSF Anti-DDoS ICMP Flood Action
       capability.  This can be used
         "Base identity for content security control. Content security
          control is an extension point
       for Anti-DDoS ICMP Flood Action NSF that evaluates a packet's payload such as an advanced NSF.";
    reference
      "RFC 8329: Framework
          Intrusion Prevention System (IPS), URL-Filtering, Antivirus,
          and VoIP/VoLTE Filter.";
     }

     identity attack-mitigation-control {
       base advanced-nsf;
       description
         "Base identity for Interface to Network Security
       Functions - Advanced attack mitigation control. Attack mitigation
          control is an NSF Anti-DDoS ICMP Flood Action
       capability"; that mitigates an attack such as anti-DDoS
          or DDoS-mitigator.";
     }

     identity icmpv6-flood-action ips {
       base anti-ddos-capability; content-security-control;
       description
      "Identity
         "Base identity for advanced NSF Anti-DDoS ICMPv6 Flood Action
       capability.  This can be used IPS (Intrusion Prevention System) capability
          that prevents malicious activity within a network";
     }
     identity url-filtering {
       base content-security-control;
       description
         "Base identity for an extension point url filtering capability that limits access by
          comparing the web traffic's URL with the URLs for Anti-DDoS ICMPv6 Flood Action as an advanced NSF.";
    reference
      "RFC 8329: Framework web filtering
          in a database";
     }

     identity anti-virus {
       base content-security-control;
       description
         "Base identity for Interface anti-virus capability to Network Security
       Functions - Advanced NSF Anti-DDoS ICMPv6 Flood Action
       capability"; protect the network
          by detecting and removing viruses.";
     }

     identity sip-flood-action voip-volte-filtering {
       base anti-ddos-capability; content-security-control;
       description
      "Identity
         "Base identity for advanced NSF Anti-DDoS SIP Flood Action
       capability.  This can be used for an extension point
       for Anti-DDoS SIP Flood Action as an advanced NSF."; VoIP/VoLTE Security Service
          capability to filter the VoIP/VoLTE packets or flows.";
       reference
         "RFC 8329: Framework 3261: SIP: Session Initiation Protocol";
     }

     identity anti-ddos {
       base attack-mitigation-control;
       description
         "Base identity for Interface to Network Security
       Functions - Advanced advanced NSF Anti-DDoS SIP Flood Action
       capability"; Attack or DDoS Mitigator
          capability.";
     }

     identity detect-mode packet-rate {
       base anti-ddos-capability; anti-ddos;
       description
         "Identity for advanced NSF Anti-DDoS Detection Mode
       capability.  This can be used for an extension point
       for Anti-DDoS Detection Mode detecting Packet Rate
          Capability where a packet rate is defined as an advanced NSF.";
    reference
      "RFC 8329: Framework for Interface to Network Security
       Functions - Advanced the arrival rate of
          Packets toward a victim destination node.  The NSF Anti-DDoS Detection Mode
       capability"; with this
          capability can detect the incoming packet rate and create an
          alert if the rate exceeds the threshold.";

     }

     identity baseline-learning flow-rate {
       base anti-ddos-capability; anti-ddos;
       description
         "Identity for advanced NSF Anti-DDoS Baseline Learning
       capability.  This can be used for an extension point
       for Anti-DDoS Baseline Learning detecting Flow Rate
          Capability where a flow rate is defined as an advanced NSF.";
    reference
      "RFC 8329: Framework for Interface to Network Security
       Functions - Advanced the arrival rate of
          flows towards a victim destination node.  The NSF Anti-DDoS Baseline Learning
       capability"; with this
          capability can detect the incoming flow rate and create an
          alert if the rate exceeds the threshold.";
     }

     identity signature-set byte-rate {
       base ips-capability; anti-ddos;
       description
         "Identity for advanced NSF IPS Signature Set capability.
       This Anti-DDoS detecting Byte Rate
          Capability where a byte rate is defined as the arrival rate of
          Bytes toward a victim destination node.  The NSF with this
          capability can be used for detect the incoming byte rate and create an extension point
          alert if the rate exceeds the threshold.";
     }

     identity signature-set {
       base ips;
       description
         "Identity for the capability of IPS to set the signature.
          Signature
       Set as is a set of rules to detect an advanced NSF."; intrusive activity.";
       reference
         "RFC 8329: Framework for Interface to Network Security
       Functions 4766:  Intrusion Detection Message Exchange Requirements - Advanced NSF IPS Signature Set capability";
          Section 2.2.13";
     }

     identity ips-exception-signature exception-signature {
       base ips-capability; ips;
       description
         "Identity for advanced NSF IPS Exception Signature
       capability.  This can be used for an extension point for the capability of IPS Exception Signature as an advanced NSF."; to exclude signatures from
          detecting the intrusion.";
       reference
         "RFC 8329: Framework 4766:  Intrusion Detection Message Exchange Requirements -
          Section 2.2.13";
     }

     identity detect {
       base anti-virus;
       description
         "Identity for Interface advanced NSF Antivirus capability to detect viruses
          using a security profile. The security profile is used to Network Security
       Functions - Advanced scan
          threats, such as virus, malware, and spyware. The NSF IPS Exception Signature Set
       capability"; should
          be able to update the security profile.";
     }

     identity voip-volte-call-id exception-files {
       base voip-volte-capability; anti-virus;
       description
         "Identity for advanced NSF VoIP/VoLTE Call Identifier (ID)
       capability.  This can be used for an extension point for
       VoIP/VoLTE Call ID as an advanced NSF.";
    reference
      "RFC 3261: SIP: Session Initiation Protocol"; Antivirus capability to exclude a
          certain file type or name from detection.";

     }

     identity user-agent pre-defined {
       base voip-volte-capability; url-filtering;
       description
         "Identity for advanced NSF VoIP/VoLTE User Agent pre-defined URL Database condition capability.
       This can be used for an extension point
          where URL database is a public database for VoIP/VoLTE
       User Agent as an advanced NSF.";
    reference
      "RFC 3261: SIP: Session Initiation Protocol"; URL filtering.";
     }

     identity ipsec-capability user-defined {
       base url-filtering;
       description
      "Base identity
         "Identity for an IPsec capability";
    reference
      "draft-ietf-i2nsf-sdn-ipsec-flow-protection-12:
       Software-Defined Networking (SDN)-based IPsec Flow
       Protection - IPsec methods such as IKE and IKE-less"; user-defined URL Database condition capability.
          that allows a users manual addition of URLs for URL
          filtering.";
     }

     identity ike call-id {
       base ipsec-capability; voip-volte-filtering;
       description
         "Identity for an IPsec Internet Key Exchange (IKE)
      capability";
    reference
      "draft-ietf-i2nsf-sdn-ipsec-flow-protection-12:
       Software-Defined Networking (SDN)-based IPsec Flow
       Protection - IPsec method with IKE.
       RFC 7296: Internet Key Exchange Protocol Version 2
       (IKEv2) - IKE as a component of IPsec used for
       performing mutual authentication and establishing and
       maintaining Security Associations (SAs)."; advanced NSF VoIP/VoLTE Call Identifier (ID)
          capability.";
     }

     identity ikeless user-agent {
       base ipsec-capability; voip-volte-filtering;
       description
         "Identity for an IPsec without Internet Key Exchange (IKE)
      capability";
    reference
      "draft-ietf-i2nsf-sdn-ipsec-flow-protection-12:
       Software-Defined Networking (SDN)-based IPsec Flow
       Protection - IPsec method without IKE"; advanced NSF VoIP/VoLTE User Agent capability.";
     }

     /*
      *  Grouping
      */

     grouping nsf-capabilities {
       description
         "Network Security Function (NSF) Capabilities";
       reference
         "RFC 8329: Framework for Interface to Network Security
          Functions - I2NSF Flow Security Policy Structure.";

       leaf-list directional-capabilities {
         type identityref {
           base directional-capability; directional;
         }
         description
           "The capability of an NSF for handling directional traffic
            flow (i.e., unidirectional or bidirectional traffic flow).";

       }

    leaf-list time-capabilities {
      type enumeration {
        enum absolute-time {
          description
            "absolute time capabilities.
             If a network security function has the absolute time
             capability, the network security function supports
             rule execution according to absolute time.";
        }
        enum periodic-time {
          description
            "periodic time capabilities.
             If a network security function has the periodic time
             capability, the network security function supports
             rule execution according to periodic time.";
        }
      }
      description
        "Time capabilities";
    }

       container event-capabilities {
         description
           "Capabilities of events.
            If a network security function has the event capabilities,
            the network security function supports rule execution
            according to system event and system alarm.";

         reference
           "RFC 8329: Framework for Interface to Network Security
            Functions - I2NSF Flow Security Policy Structure.
         draft-ietf-i2nsf-nsf-monitoring-data-model-04: Section 7.
            draft-ietf-i2nsf-nsf-monitoring-data-model-09: I2NSF
            NSF Monitoring YANG Data Model - System Alarm and
            System Events.";

         leaf-list system-event-capability {
           type identityref {
             base system-event-capability; system-event;
           }
           description
             "System event capabilities";
         }

         leaf-list system-alarm-capability {
           type identityref {
             base system-alarm;
           }
           description
             "System event alarm capabilities";
         }

         leaf-list system-alarm-capability time-capabilities {
           type identityref {
             base system-alarm-capability; time;
           }
           description
          "System alarm capabilities";
             "The capabilities for activating the policy within a specific
              time.";
         }
       }

       container condition-capabilities {
         description
           "Conditions capabilities.";
         container generic-nsf-capabilities {
           description
             "Conditions capabilities.

              If a network security function has the condition
              capabilities, the network security function
              supports rule execution according to conditions of
              IPv4, IPv6, TCP, UDP, SCTP, DCCP, ICMP, ICMPv6, or
           payload."; ICMPv6.";
           reference
             "RFC 768: User Datagram Protocol - UDP.
              RFC 791: Internet Protocol - IPv4.
              RFC 792: Internet Control Message Protocol - ICMP.
              RFC 793: Transmission Control Protocol - TCP.
              RFC 768: User Datagram 4443: Internet Control Message Protocol (ICMPv6)
              for the Internet Protocol Version 6 (IPv6) Specification
              - UDP. ICMPv6.
              RFC 4960: Stream Control Transmission Protocol - SCTP.
              RFC 8200: Internet Protocol, Version 6 (IPv6)
              Specification - IPv6.
              RFC 4443: Internet Control Message Protocol (ICMPv6)
           for the Internet Protocol Version 6 (IPv6) Specification
           - ICMPv6.
           RFC 8329: Framework for Interface to Network Security
              Functions - I2NSF Flow Security Policy Structure.";

           leaf-list ipv4-capability ethernet-capability {
             type identityref {
               base ipv4-capability; ethernet;
             }
             description
            "IPv4 packet
               "Media Access Control (MAC) capabilities";
             reference
            "RFC 791: Internet Protocol";
               "IEEE 802.3: IEEE Standard for Ethernet";
           }

           leaf-list icmp-capability ipv4-capability {
             type identityref {
               base icmp-capability; ipv4;
             }
             description
            "ICMP
               "IPv4 packet capabilities";
             reference
               "RFC 792: 791: Internet Control Message Protocol - ICMP"; Protocol";
           }

           leaf-list ipv6-capability {
             type identityref {
               base ipv6-capability; ipv6;
             }
             description
               "IPv6 packet capabilities";
             reference
               "RFC 8200: Internet Protocol, Version 6 (IPv6)
                Specification - IPv6";
           }
           leaf-list icmpv4-capability {
             type identityref {
               base icmpv4;
             }
             description
               "ICMPv4 packet capabilities";
             reference
               "RFC 792: Internet Control Message Protocol - ICMP";
           }

           leaf-list icmpv6-capability {
             type identityref {
               base icmpv6-capability; icmpv6;
             }
             description
               "ICMPv6 packet capabilities";
             reference
               "RFC 4443: Internet Control Message Protocol (ICMPv6)
                for the Internet Protocol Version 6 (IPv6) Specification
                - ICMPv6";
           }

           leaf-list tcp-capability {
             type identityref {
               base tcp-capability; tcp;
             }
             description
               "TCP packet capabilities";
             reference
               "RFC 793: Transmission Control Protocol - TCP
             draft-ietf-tcpm-rfc793bis-19:
                draft-ietf-tcpm-rfc793bis-24: Transmission Control
                Protocol (TCP) Specification";
           }

           leaf-list udp-capability {
             type identityref {
               base udp-capability; udp;
             }
             description
               "UDP packet capabilities";
             reference
               "RFC 768: User Datagram Protocol - UDP";
           }

           leaf-list sctp-capability {
             type identityref {
               base sctp-capability; sctp;
             }
             description
               "SCTP packet capabilities";
             reference
               "RFC 4960: Stream Control Transmission Protocol - SCTP";
           }

           leaf-list dccp-capability {
             type identityref {
               base dccp-capability; dccp;
             }
             description
               "DCCP packet capabilities";
             reference
               "RFC 4340: Datagram Congestion Control Protocol - DCCP";
           }
         }

         container advanced-nsf-capabilities {
           description
             "Advanced Network Security Function (NSF) capabilities,
              such as Anti-Virus, Anti-DDoS, IPS, and VoIP/VoLTE.
              This container contains the leaf-lists of advanced
              NSF capabilities";
        reference
          "RFC 8329: Framework for Interface to Network Security
           Functions - Advanced NSF

           leaf-list anti-ddos-capability {
             type identityref {
               base anti-ddos;
             }
             description
               "Anti-DDoS Attack capabilities";
           }

           leaf-list ips-capability {
             type identityref {
               base ips;
             }
             description
               "IPS capabilities";
           }

           leaf-list anti-virus-capability {
             type identityref {
               base anti-virus-capability; anti-virus;
             }
             description
               "Anti-Virus capabilities";
          reference
            "RFC 8329: Framework for Interface to Network Security
             Functions - Advanced NSF Anti-Virus capabilities";
           }
           leaf-list anti-ddos-capability url-capability {
             type identityref {
               base anti-ddos-capability; url-filtering;
             }
             description
            "Anti-DDoS Attack capabilities";
          reference
            "RFC 8329: Framework for Interface to Network Security
             Functions - Advanced NSF Anti-DDoS Attack
               "URL capabilities";
           }

           leaf-list ips-capability voip-volte-filtering-capability {
             type identityref {
               base ips-capability; voip-volte-filtering;
            }
             description
            "IPS
               "VoIP/VoLTE capabilities";
          reference
            "RFC 8329: Framework for Interface to Network Security
             Functions - Advanced NSF IPS
           }
         }

         container context-capabilities {
           description
             "Security context capabilities";
           leaf-list application-filter-capabilities{
             type identityref {
               base application-protocol;
             }
             description
               "Context capabilities based on the application protocol";
           }

           leaf-list url-capability target-capabilities {
             type identityref {
               base url-capability; target-device;
             }
             description
            "URL capabilities";
          reference
            "RFC 8329: Framework for Interface to Network Security
             Functions - Advanced
               "Context capabilities based on the device attribute that
               can identify a device type
               (i.e., router, switch, pc, ios, or android).";
           }

           leaf-list user-condition-capabilities {
             type identityref {
               base user-condition;
             }
             description
               "Context capabilities based on user condition, such as
                user-id or user-name. The users can collected into a
                user-group and identified with group-id or group-name.
                An NSF URL capabilities";
        }

        leaf-list voip-volte-capability {
          type identityref {
            base voip-volte-capability;
         }
          description
            "VoIP/VoLTE capabilities";

          reference
            "RFC 8329: Framework for Interface to Network Security
             Functions - Advanced is aware of the IP address of the user provided by
                a unified user management system via network. Based on
                name-address association, an NSF VoIP/VoLTE capabilities";
        } is able to enforce the
                security functions over the given user (or user group)";
           }

           leaf-list context-capabilities geography-capabilities {
             type identityref {
               base context-capability; geography-location;
             }
             description
          "Security context capabilities";
               "Context condition capabilities based on the geographical
                location of the source or destination";
           }
         }
       }

       container action-capabilities {
         description
           "Action capabilities.
            If a network security function has the action capabilities,
            the network security function supports the attendant
            actions for policy rules.";

         leaf-list ingress-action-capability {
           type identityref {
             base ingress-action-capability; ingress-action;
           }
           description
             "Ingress-action capabilities";
         }

         leaf-list egress-action-capability {
           type identityref {
             base egress-action-capability; egress-action;
           }
           description
             "Egress-action capabilities";
         }

         leaf-list log-action-capability {
           type identityref {
             base log-action-capability; log-action;
           }
           description
             "Log-action capabilities";
         }
       }

       leaf-list resolution-strategy-capabilities {
         type identityref {
           base resolution-strategy-capability; resolution-strategy;
         }
         description
           "Resolution strategy capabilities.
            The resolution strategies can be used to specify how
            to resolve conflicts that occur between the actions
            of the same or different policy rules that are matched
            for the same packet and by particular NSF.";
       }

       leaf-list default-action-capabilities {
         type identityref {
           base default-action-capability; default-action;
         }
         description
           "Default action capabilities.
            A default action is used to execute I2NSF policy rules
            when no rule matches a packet. The default action is
            defined as pass, drop, alert, rate-limit, or mirror.  Note that
         alert makes a packet dropped and logged.";
      reference
        "RFC 8329: Framework for Interface to Network Security
         Functions - Ingress and egress actions.";
    }

    leaf-list ipsec-method {
      type identityref {
        base ipsec-capability;
      }
      description
        "IPsec method capabilities";
      reference
        "draft-ietf-i2nsf-sdn-ipsec-flow-protection-12:
         Software-Defined Networking (SDN)-based IPsec Flow
         Protection - IPsec methods such as IKE and IKE-less"; mirror.";
       }
     }

     /*
      * Data nodes
      */

     list nsf {
       key "nsf-name";
       description
         "The list of Network Security Functions (NSFs)";
       leaf nsf-name {
         type string;
         mandatory true;
         description
           "The name of Network Security Function (NSF)";
       }
       uses nsf-capabilities;
     }
   }
   <CODE ENDS>

               Figure 3: YANG Data Module of I2NSF Capability

7.  IANA Considerations

   This document requests IANA to register the following URI in the
   "IETF XML Registry" [RFC3688]:

   ID: yang:ietf-i2nsf-capability
   URI: urn:ietf:params:xml:ns:yang:ietf-i2nsf-capability
   Registrant Contact: The IESG.
   XML: N/A; the requested URI is an XML namespace.
   Filename: [ TBD-at-Registration ]
   Reference: [ RFC-to-be ]

   This document requests IANA to register the following YANG module in
   the "YANG Module Names" registry [RFC7950][RFC8525]:

   Name: ietf-i2nsf-capability
   Maintained by IANA? N
   Namespace: urn:ietf:params:xml:ns:yang:ietf-i2nsf-capability
   Prefix: nsfcap
   Module:
   Reference: [ RFC-to-be ]

8.  Privacy Considerations

   This YANG module specified in this document make a trade-off between
   privacy and security. specifies the capabilities for NSFs.  Some part of the YANG data model specified
   capabilities in this document might use MAY require highly sensitive private
   data of the client. to operate properly.  The data used in this YANG data model can usage of such capability MUST be used for
   reported to the NSFs users and permitted before using the private
   information related to
   improve the security capability.  Using any of the network. capabilities
   that require private data MUST preserve the privacy by preventing any
   leakage or unauthorized disclosure of the private data.

   In regards to the privacy data used, the security for accessibility
   of the data should be tightly secured and monitored.  The Security
   Considerations are discussed in Section 9.

9.  Security Considerations

   The YANG module specified in this document defines a data schema
   designed to be accessed through network management protocols such as
   NETCONF [RFC6241] or RESTCONF [RFC8040].  The lowest layer of NETCONF
   protocol layers can MUST use Secure Shell (SSH) [RFC4254][RFC6242] as a
   secure transport layer.  The lowest layer of RESTCONF protocol layers
   can
   MUST use HTTP over Transport Layer Security (TLS), that is, HTTPS
   [RFC7230][RFC8446] as a secure transport layer.

   The Network Configuration Access Control Model (NACM) [RFC8341]
   provides a means of restricting access to specific NETCONF or
   RESTCONF users to a preconfigured subset of all available NETCONF or
   RESTCONF protocol operations and contents.  Thus, NACM can SHOULD be used
   to restrict the NSF registration from unauthorized users.

   There are a number of data nodes defined in this YANG module that are
   writable, creatable, and deletable (i.e., config true, which is the
   default).  These data nodes may be considered sensitive or vulnerable
   in some network environments.  Write operations to these data nodes
   could have a negative effect on network and security operations.
   These data nodes are collected into a single list node.  This list
   node is defined by list nsf with the following sensitivity/
   vulnerability:

   o

   *  list nsf: An attacker could alter the security capabilities
      associated with an NSF by disabling or enabling the functionality
      of the security capabilities of the NSF.

   Some of the readable data nodes in this YANG module may be considered
   sensitive or vulnerable in some network environments.  It is thus
   important to control read access (e.g., via get, get-config, or
   notification) to these data nodes.  These are the subtrees and data
   nodes with their sensitivity/vulnerability:

   *  list nsf: An The leak of this node to an attacker could alter reveal the
      specific configuration of security capabilities
      associated with controls to an NSF by disabling attacker.  An
      attacker can craft an attack path that avoids observation or enabling
      mitigations; one may reveal topology information to inform
      additional targets or enable lateral movement; one enables the functionality
      construction of an attack path that avoids observation or
      mitigations; one provides an indication that the security capabilities of operator has
      discovered the NSF. attack.

   Some of the features that this document defines capability indicators
   for are highly sensitive and/or privileged operations (e.g.,
   listening to VoIP/VoLTE audio to identify individuals and web
   filtering) that inherently
   require access to individuals' private data.  These are subtrees and
   data nodes that are considered privacy sensitive:

   *  voip-volte-filtering-capability: The NSF that is able to filter
      VoIP/VoLTE calls might identify certain individual identification.

   *  user-condition-capabilities: The capability uses a set of IP
      addresses mapped to users.

   *  geography-capabilities: The IP address used in this capability can
      identify a user's geographical location.

   It is noted that some private information is made accessible in this
   manner.  Thus, the nodes/entities given access to this data need
   to MUST be
   tightly secured and secured, monitored, and audited to prevent leakage or other
   unauthorized disclosure of private data.  Refer to [RFC6973] for the
   description of privacy aspects that protocol designers (including
   YANG data model designers) should consider along with regular
   security and privacy analysis.

10.  References

10.1.  Normative References

   [I-D.ietf-i2nsf-nsf-monitoring-data-model]
              Jeong, J., Lingga, P., Hares, S., Xia, L., and H.
              Birkholz, "I2NSF NSF Monitoring YANG Data Model", draft-
              ietf-i2nsf-nsf-monitoring-data-model-04 (work in
              progress), September 2020.

   [I-D.ietf-i2nsf-sdn-ipsec-flow-protection]
              Marin-Lopez, R., Lopez-Millan, G., and F. Pereniguez-
              Garcia, "Software-Defined Networking (SDN)-based IPsec
              Flow Protection", draft-ietf-i2nsf-sdn-ipsec-flow-
              protection-12 (work in progress), October 2020.

   [I-D.ietf-tcpm-accurate-ecn]
              Briscoe, B., Kuehlewind, M., and R. Scheffenegger, "More
              Accurate ECN Feedback in TCP", draft-ietf-tcpm-accurate-
              ecn-13 (work in progress), November 2020.

   [I-D.ietf-tcpm-rfc793bis]
              Eddy, W., "Transmission Control Protocol (TCP)
              Specification", draft-ietf-tcpm-rfc793bis-20 (work in
              progress), January 2021.

   [I-D.ietf-tsvwg-udp-options]
              Touch, J., "Transport Options for UDP", draft-ietf-tsvwg-
              udp-options-09 (work in progress), November 2020.

   [RFC0768]  Postel, J., "User Datagram Protocol", STD 6, RFC 768,
              DOI 10.17487/RFC0768, August 1980,
              <https://www.rfc-editor.org/info/rfc768>.

   [RFC0791]  Postel, J., "Internet Protocol", STD 5, RFC 791,
              DOI 10.17487/RFC0791, September 1981,
              <https://www.rfc-editor.org/info/rfc791>.

   [RFC0792]  Postel, J., "Internet Control Message Protocol", STD 5,
              RFC 792, DOI 10.17487/RFC0792, September 1981,
              <https://www.rfc-editor.org/info/rfc792>.

   [RFC0793]  Postel, J., "Transmission Control Protocol", STD 7,
              RFC 793, DOI 10.17487/RFC0793, September 1981,
              <https://www.rfc-editor.org/info/rfc793>.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/info/rfc2119>.

   [RFC2474]  Nichols, K., Blake, S., Baker, F., and D. Black,
              "Definition of the Differentiated Services Field (DS
              Field) in the IPv4 and IPv6 Headers", RFC 2474,
              DOI 10.17487/RFC2474, December 1998,
              <https://www.rfc-editor.org/info/rfc2474>.

   [RFC3168]  Ramakrishnan, K., Floyd, S., and D. Black, "The Addition
              of Explicit Congestion Notification (ECN) to IP",
              RFC 3168, DOI 10.17487/RFC3168, September 2001,
              <https://www.rfc-editor.org/info/rfc3168>.

   [RFC3261]  Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston,
              A., Peterson, J., Sparks, R., Handley, M., and E.
              Schooler, "SIP: Session Initiation Protocol", RFC 3261,
              DOI 10.17487/RFC3261, June 2002,
              <https://www.rfc-editor.org/info/rfc3261>.

   [RFC3501]  Crispin, M., "INTERNET MESSAGE ACCESS PROTOCOL - VERSION
              4rev1", RFC 3501, DOI 10.17487/RFC3501, March 2003,
              <https://www.rfc-editor.org/info/rfc3501>.

   [RFC3688]  Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
              DOI 10.17487/RFC3688, January 2004,
              <https://www.rfc-editor.org/info/rfc3688>.

   [RFC4254]  Ylonen, T. and C. Lonvick, Ed., "The Secure Shell (SSH)
              Connection Protocol", RFC 4254, DOI 10.17487/RFC4254,
              January 2006, <https://www.rfc-editor.org/info/rfc4254>.

   [RFC4340]  Kohler, E., Handley, M., and S. Floyd, "Datagram
              Congestion Control Protocol (DCCP)", RFC 4340,
              DOI 10.17487/RFC4340, March 2006,
              <https://www.rfc-editor.org/info/rfc4340>.

   [RFC4443]  Conta, A., Deering, S., and M. Gupta, Ed., "Internet
              Control Message Protocol (ICMPv6) for the Internet
              Protocol Version 6 (IPv6) Specification", STD 89,
              RFC 4443, DOI 10.17487/RFC4443, March 2006,
              <https://www.rfc-editor.org/info/rfc4443>.

   [RFC4960]  Stewart, R., Ed., "Stream Control Transmission Protocol",
              RFC 4960, DOI 10.17487/RFC4960, September 2007,
              <https://www.rfc-editor.org/info/rfc4960>.

   [RFC5595]  Fairhurst, G., "The Datagram Congestion Control Protocol
              (DCCP) Service Codes", RFC 5595, DOI 10.17487/RFC5595,
              September 2009, <https://www.rfc-editor.org/info/rfc5595>.

   [RFC6020]  Bjorklund, M., Ed., "YANG - A Data Modeling Language for
              the Network Configuration Protocol (NETCONF)", RFC 6020,
              DOI 10.17487/RFC6020, October 2010,
              <https://www.rfc-editor.org/info/rfc6020>.

   [RFC6241]  Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
              and A. Bierman, Ed., "Network Configuration Protocol
              (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011,
              <https://www.rfc-editor.org/info/rfc6241>.

   [RFC6242]  Wasserman, M., "Using the NETCONF Protocol over Secure
              Shell (SSH)", RFC 6242, DOI 10.17487/RFC6242, June 2011,
              <https://www.rfc-editor.org/info/rfc6242>.

   [RFC6335]  Cotton, M., Eggert, L., Touch, J., Westerlund, M., and S.
              Cheshire, "Internet Assigned Numbers Authority (IANA)
              Procedures for the Management of the Service Name and
              Transport Protocol Port Number Registry", BCP 165,
              RFC 6335, DOI 10.17487/RFC6335, August 2011,
              <https://www.rfc-editor.org/info/rfc6335>.

   [RFC6437]  Amante, S., Carpenter, B., Jiang, S., and J. Rajahalme,
              "IPv6 Flow Label Specification", RFC 6437,
              DOI 10.17487/RFC6437, November 2011,
              <https://www.rfc-editor.org/info/rfc6437>.

   [RFC6691]  Borman, D., "TCP Options and Maximum Segment Size (MSS)",
              RFC 6691, DOI 10.17487/RFC6691, July 2012,
              <https://www.rfc-editor.org/info/rfc6691>.

   [RFC6864]  Touch, J., "Updated Specification of the IPv4 ID Field",
              RFC 6864, DOI 10.17487/RFC6864, February 2013,
              <https://www.rfc-editor.org/info/rfc6864>.

   [RFC6973]  Cooper, A., Tschofenig, H., Aboba, B., Peterson, J.,
              Morris, J., Hansen, M., and R. Smith, "Privacy
              Considerations for Internet Protocols", RFC 6973,
              DOI 10.17487/RFC6973, July 2013,
              <https://www.rfc-editor.org/info/rfc6973>.

   [RFC6991]  Schoenwaelder, J., Ed., "Common YANG Data Types",
              RFC 6991, DOI 10.17487/RFC6991, July 2013,
              <https://www.rfc-editor.org/info/rfc6991>.

   [RFC7230]  Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
              Protocol (HTTP/1.1): Message Syntax and Routing",
              RFC 7230, DOI 10.17487/RFC7230, June 2014,
              <https://www.rfc-editor.org/info/rfc7230>.

   [RFC7231]  Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
              Protocol (HTTP/1.1): Semantics and Content", RFC 7231,
              DOI 10.17487/RFC7231, June 2014,
              <https://www.rfc-editor.org/info/rfc7231>.

   [RFC7296]  Kaufman, C., Hoffman, P., Nir, Y., Eronen, P., and T.
              Kivinen, "Internet Key Exchange Protocol Version 2
              (IKEv2)", STD 79, RFC 7296, DOI 10.17487/RFC7296, October
              2014, <https://www.rfc-editor.org/info/rfc7296>.

   [RFC7323]  Borman, D., Braden, B., Jacobson, V., and R.
              Scheffenegger, Ed., "TCP Extensions for High Performance",
              RFC 7323, DOI 10.17487/RFC7323, September 2014,
              <https://www.rfc-editor.org/info/rfc7323>.

   [RFC7950]  Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
              RFC 7950, DOI 10.17487/RFC7950, August 2016,
              <https://www.rfc-editor.org/info/rfc7950>.

   [RFC8040]  Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
              Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
              <https://www.rfc-editor.org/info/rfc8040>.

   [RFC8192]  Hares, S., Lopez, D., Zarny, M., Jacquenet, C., Kumar, R.,
              and J. Jeong, "Interface to Network Security Functions
              (I2NSF): Problem Statement and Use Cases", K. Watsen, "RESTCONF
              Protocol", RFC 8192, 8040, DOI 10.17487/RFC8192, July 10.17487/RFC8040, January 2017,
              <https://www.rfc-editor.org/info/rfc8192>.
              <https://www.rfc-editor.org/info/rfc8040>.

   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/info/rfc8174>.

   [RFC8200]  Deering, S. and R. Hinden, "Internet Protocol, Version 6
              (IPv6) Specification", STD 86, RFC 8200,
              DOI 10.17487/RFC8200, July 2017,
              <https://www.rfc-editor.org/info/rfc8200>.

   [RFC8329]  Lopez, D., Lopez, E., Dunbar, L., Strassner, J., and R.
              Kumar, "Framework for Interface to Network Security
              Functions", RFC 8329, DOI 10.17487/RFC8329, February 2018,
              <https://www.rfc-editor.org/info/rfc8329>.

   [RFC8340]  Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams",
              BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018,
              <https://www.rfc-editor.org/info/rfc8340>.

   [RFC8341]  Bierman, A. and M. Bjorklund, "Network Configuration
              Access Control Model", STD 91, RFC 8341,
              DOI 10.17487/RFC8341, March 2018,
              <https://www.rfc-editor.org/info/rfc8341>.

   [RFC8407]  Bierman, A., "Guidelines for Authors and Reviewers of
              Documents Containing YANG Data Models", BCP 216, RFC 8407,
              DOI 10.17487/RFC8407, October 2018,
              <https://www.rfc-editor.org/info/rfc8407>.

   [RFC8446]  Rescorla, E., "The Transport Layer Security (TLS) Protocol
              Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018,
              <https://www.rfc-editor.org/info/rfc8446>.

   [RFC8525]  Bierman, A., Bjorklund, M., Schoenwaelder, J., Watsen, K.,
              and R. Wilton, "YANG Library", RFC 8525,
              DOI 10.17487/RFC8525, March 2019,
              <https://www.rfc-editor.org/info/rfc8525>.

   [RFC8519]  Jethanandani, M., Agarwal, S., Huang, L., and D. Blair,
              "YANG Data Model for Network Access Control Lists (ACLs)",
              RFC 8519, DOI 10.17487/RFC8519, March 2019,
              <https://www.rfc-editor.org/info/rfc8519>.

   [RFC8525]  Bierman,

   [I-D.ietf-tcpm-accurate-ecn]
              Briscoe, B., K├╝hlewind, M., and R. Scheffenegger, "More
              Accurate ECN Feedback in TCP", Work in Progress, Internet-
              Draft, draft-ietf-tcpm-accurate-ecn-15, 12 July 2021,
              <https://www.ietf.org/archive/id/draft-ietf-tcpm-accurate-
              ecn-15.txt>.

   [I-D.ietf-tsvwg-udp-options]
              Touch, J., "Transport Options for UDP", Work in Progress,
              Internet-Draft, draft-ietf-tsvwg-udp-options-13, 19 June
              2021, <https://www.ietf.org/archive/id/draft-ietf-tsvwg-
              udp-options-13.txt>.

   [I-D.ietf-i2nsf-nsf-monitoring-data-model]
              Jeong, J. (., Lingga, P., Hares, S., Xia, L. (., and H.
              Birkholz, "I2NSF NSF Monitoring Interface YANG Data
              Model", Work in Progress, Internet-Draft, draft-ietf-
              i2nsf-nsf-monitoring-data-model-08, 29 April 2021,
              <https://www.ietf.org/archive/id/draft-ietf-i2nsf-nsf-
              monitoring-data-model-08.txt>.

   [I-D.ietf-i2nsf-nsf-facing-interface-dm]
              Kim, J. (., Jeong, J. (., Park, J., Hares, S., and Q. Lin,
              "I2NSF Network Security Function-Facing Interface YANG
              Data Model", Work in Progress, Internet-Draft, draft-ietf-
              i2nsf-nsf-facing-interface-dm-12, 8 March 2021,
              <https://www.ietf.org/archive/id/draft-ietf-i2nsf-nsf-
              facing-interface-dm-12.txt>.

   [I-D.ietf-i2nsf-registration-interface-dm]
              Hyun, S., Jeong, J. P., Roh, T., Wi, S., and J. Park,
              "I2NSF Registration Interface YANG Data Model", Work in
              Progress, Internet-Draft, draft-ietf-i2nsf-registration-
              interface-dm-10, 21 February 2021,
              <https://www.ietf.org/archive/id/draft-ietf-i2nsf-
              registration-interface-dm-10.txt>.

10.2.  Informative References

   [RFC6691]  Borman, D., "TCP Options and Maximum Segment Size (MSS)",
              RFC 6691, DOI 10.17487/RFC6691, July 2012,
              <https://www.rfc-editor.org/info/rfc6691>.

   [RFC6973]  Cooper, A., Bjorklund, Tschofenig, H., Aboba, B., Peterson, J.,
              Morris, J., Hansen, M., Schoenwaelder, and R. Smith, "Privacy
              Considerations for Internet Protocols", RFC 6973,
              DOI 10.17487/RFC6973, July 2013,
              <https://www.rfc-editor.org/info/rfc6973>.

   [RFC8192]  Hares, S., Lopez, D., Zarny, M., Jacquenet, C., Kumar, R.,
              and J. Jeong, "Interface to Network Security Functions
              (I2NSF): Problem Statement and Use Cases", RFC 8192,
              DOI 10.17487/RFC8192, July 2017,
              <https://www.rfc-editor.org/info/rfc8192>.

   [RFC8329]  Lopez, D., Lopez, E., Dunbar, L., Strassner, J., Watsen, and R.
              Kumar, "Framework for Interface to Network Security
              Functions", RFC 8329, DOI 10.17487/RFC8329, February 2018,
              <https://www.rfc-editor.org/info/rfc8329>.

   [RFC8805]  Kline, E., Duleba, K., Szamonek, Z., Moser, S., and R. Wilton, "YANG Library", W.
              Kumari, "A Format for Self-Published IP Geolocation
              Feeds", RFC 8525, 8805, DOI 10.17487/RFC8525, March 2019,
              <https://www.rfc-editor.org/info/rfc8525>.

10.2.  Informative References 10.17487/RFC8805, August 2020,
              <https://www.rfc-editor.org/info/rfc8805>.

   [I-D.ietf-tcpm-rfc793bis]
              Eddy, W. M., "Transmission Control Protocol (TCP)
              Specification", Work in Progress, Internet-Draft, draft-
              ietf-tcpm-rfc793bis-24, 12 July 2021,
              <https://www.ietf.org/archive/id/draft-ietf-tcpm-
              rfc793bis-24.txt>.

   [IANA-Protocol-Numbers]
              "Assigned Internet Protocol Numbers", Available:
              https://www.iana.org/assignments/protocol-
              numbers/protocol-numbers.xhtml, September 2020.

   [Alshaer]  Shaer, Al., Hamed, E., and H. Hamed, "Modeling and
              management of firewall policies", 2004.

   [Galitsky] Galitsky, B. and R. Pampapathi, "Can many agents answer
              questions better than one", First
              Monday http://dx.doi.org/10.5210/fm.v10i1.1204, 2005.

   [Hirschman]
              Hirschman, L. and R. Gaizauskas, "Natural Language
              Question Answering: The View from Here", Natural Language
              Engineering 7:4, pgs 275-300, Cambridge University Press ,
              Nov
              November 2001.

   [Hohpe]    Hohpe, G. and B. Woolf, "Enterprise Integration Patterns",
              ISBN 0-32-120068-3 , 2003.

   [IANA-Protocol-Numbers]
              "Assigned Internet Protocol Numbers", Available:
              https://www.iana.org/assignments/protocol-
              numbers/protocol-numbers.xhtml, September 2020.

   [Martin]   Martin, R., R.C., "Agile Software Development, Principles,
              Patterns, and Practices", Prentice-Hall , ISBN:
              0-13-597444-5 , 2002.

   [OODMP]    "http://www.oodesign.com/mediator-pattern.html".

   [OODOP]    "http://www.oodesign.com/mediator-pattern.html".

   [OODSRP]   "http://www.oodesign.com/mediator-pattern.html".

   [RFC8805]  Kline, E., Duleba, K., Szamonek, Z., Moser, S., and W.
              Kumari, "A Format for Self-Published IP Geolocation
              Feeds", RFC 8805, DOI 10.17487/RFC8805, August 2020,
              <https://www.rfc-editor.org/info/rfc8805>.

Appendix A.  Configuration Examples

   This section shows configuration examples of "ietf-i2nsf-capability"
   module for capabilities registration of general firewall.

A.1.  Example 1: Registration for the Capabilities of a General Firewall

   This section shows a configuration example for the capabilities
   registration of a general firewall in either an IPv4 network or an
   IPv6 network.

   <nsf xmlns="urn:ietf:params:xml:ns:yang:ietf-i2nsf-capability">
    <nsf-name>general_firewall</nsf-name>
    <condition-capabilities>
     <generic-nsf-capabilities>
   <ipv4-capability>ipv4-protocol</ipv4-capability>
   <ipv4-capability>prefix-ipv4-address-flow-direction</ipv4-capability>
   <ipv4-capability>prefix-ipv4-address</ipv4-capability>
   <ipv4-capability>range-ipv4-address-flow-direction</ipv4-capability>
   <ipv4-capability>range-ipv4-address</ipv4-capability>
   <tcp-capability>exact-tcp-port-num-flow-direction</tcp-capability>
   <tcp-capability>exact-tcp-src-port-num</tcp-capability>
   <tcp-capability>exact-tcp-dst-port-num</tcp-capability>
   <tcp-capability>range-tcp-port-num-flow-direction</tcp-capability>
   <tcp-capability>range-tcp-src-port-num</tcp-capability>
   <tcp-capability>range-tcp-dst-port-num</tcp-capability>
   <udp-capability>exact-udp-port-num-flow-direction</udp-capability>
   <udp-capability>exact-udp-src-port-num</udp-capability>
   <udp-capability>exact-udp-dst-port-num</udp-capability>
   <udp-capability>range-udp-port-num-flow-direction</udp-capability>
   <udp-capability>range-udp-src-port-num</udp-capability>
   <udp-capability>range-udp-dst-port-num</udp-capability>
      <ipv4-capability>next-header</ipv4-capability>
      <ipv4-capability>flow-direction</ipv4-capability>
      <ipv4-capability>source-address</ipv4-capability>
      <ipv4-capability>destination-address</ipv4-capability>
      <tcp-capability>source-port-number</tcp-capability>
      <tcp-capability>destination-port-number</tcp-capability>
      <udp-capability>source-port-num</udp-capability>
      <udp-capability>destination-port-num</udp-capability>
     </generic-nsf-capabilities>
    </condition-capabilities>
    <action-capabilities>
     <ingress-action-capability>pass</ingress-action-capability>
     <ingress-action-capability>drop</ingress-action-capability>
  <ingress-action-capability>alert</ingress-action-capability>
     <ingress-action-capability>mirror</ingress-action-capability>
     <egress-action-capability>pass</egress-action-capability>
     <egress-action-capability>drop</egress-action-capability>
  <egress-action-capability>alert</egress-action-capability>
     <egress-action-capability>mirror</egress-action-capability>
    </action-capabilities>
   </nsf>

      Figure 4: Configuration XML for the Capabilities Registration of
                   a General Firewall in an IPv4 Network

   Figure 4 shows the configuration XML for the capabilities
   registration of a general firewall as an NSF in an IPv4 network.  Its
   capabilities are as follows.

   1.  The name of the NSF is general_firewall.

   2.  The NSF can inspect a protocol, a prefix of the IPv4 addresses, protocol header field, flow
       direction, source address(es), and a
       range of IPv4 addresses for IPv4 packets. destination address(es)

   3.  The NSF can inspect an exact the port number number(s) and a range of port
       numbers flow direction for the
       transport layer (TCP protocol, i.e., TCP and UDP). UDP.

   4.  The NSF can control whether the packets are allowed to pass,
       drop, or alert. mirror.

   <nsf xmlns="urn:ietf:params:xml:ns:yang:ietf-i2nsf-capability">
    <nsf-name>general_firewall</nsf-name>
    <condition-capabilities>
     <generic-nsf-capabilities>
   <ipv6-capability>ipv6-next-header</ipv6-capability>
   <ipv6-capability>prefix-ipv6-address-flow-direction</ipv6-capability>
   <ipv6-capability>prefix-ipv6-address</ipv6-capability>
   <ipv6-capability>range-ipv6-address-flow-direction</ipv6-capability>
   <ipv6-capability>range-ipv6-address</ipv6-capability>
   <tcp-capability>exact-tcp-port-num-flow-direction</tcp-capability>
   <tcp-capability>exact-tcp-src-port-num</tcp-capability>
   <tcp-capability>exact-tcp-dst-port-num</tcp-capability>
   <tcp-capability>range-tcp-port-num-flow-direction</tcp-capability>
   <tcp-capability>range-tcp-src-port-num</tcp-capability>
   <tcp-capability>range-tcp-dst-port-num</tcp-capability>
   <udp-capability>exact-udp-port-num-flow-direction</udp-capability>
   <udp-capability>exact-udp-src-port-num</udp-capability>
   <udp-capability>exact-udp-dst-port-num</udp-capability>
   <udp-capability>range-udp-port-num-flow-direction</udp-capability>
   <udp-capability>range-udp-src-port-num</udp-capability>
   <udp-capability>range-udp-dst-port-num</udp-capability>
      <ipv6-capability>next-header</ipv6-capability>
      <ipv6-capability>flow-direction</ipv6-capability>
      <ipv6-capability>source-address</ipv6-capability>
      <ipv6-capability>destination-address</ipv6-capability>
      <tcp-capability>source-port-number</tcp-capability>
      <tcp-capability>destination-port-number</tcp-capability>
      <udp-capability>source-port-num</udp-capability>
      <udp-capability>destination-port-num</udp-capability>
     </generic-nsf-capabilities>
    </condition-capabilities>
    <action-capabilities>
     <ingress-action-capability>pass</ingress-action-capability>
     <ingress-action-capability>drop</ingress-action-capability>
  <ingress-action-capability>alert</ingress-action-capability>
     <ingress-action-capability>mirror</ingress-action-capability>
     <egress-action-capability>pass</egress-action-capability>
     <egress-action-capability>drop</egress-action-capability>
  <egress-action-capability>alert</egress-action-capability>
     <egress-action-capability>mirror</egress-action-capability>
    </action-capabilities>
   </nsf>

      Figure 5: Configuration XML for the Capabilities Registration of
                   a General Firewall in an IPv6 Network

   In addition, Figure 5 shows the configuration XML for the
   capabilities registration of a general firewall as an NSF in an IPv6
   network.  Its capabilities are as follows.

   1.  The name of the NSF is general_firewall.

   2.  The NSF can inspect a protocol (Next-Header), a prefix of IPv6
       addresses, next header, flow direction, source
       address(es), and a range of IPv6 addresses for IPv6 packets. destination address(es)

   3.  The NSF can inspect an exact the port number number(s) and a range of port
       numbers flow direction for the
       transport layer (TCP protocol, i.e., TCP and UDP). UDP.

   4.  The NSF can control whether the packets are allowed to pass,
       drop, or alert. mirror.

A.2.  Example 2: Registration for the Capabilities of a Time-based
      Firewall

   This section shows a configuration example for the capabilities
   registration of a time-based firewall in either an IPv4 network or an
   IPv6 network.

   <nsf xmlns="urn:ietf:params:xml:ns:yang:ietf-i2nsf-capability">
    <nsf-name>time_based_firewall</nsf-name>
    <event-capabilities>
      <time-capabilities>absolute-time</time-capabilities>
      <time-capabilities>periodic-time</time-capabilities>
    </event-capabilities>
    <condition-capabilities>
     <generic-nsf-capabilities>
      <ipv4-capability>ipv4-protocol</ipv4-capability>
   <ipv4-capability>prefix-ipv4-address-flow-direction</ipv4-capability>
   <ipv4-capability>prefix-ipv4-address</ipv4-capability>
   <ipv4-capability>range-ipv4-address-flow-direction</ipv4-capability>
   <ipv4-capability>range-ipv4-address</ipv4-capability>
      <ipv4-capability>flow-direction</ipv4-capability>
      <ipv4-capability>source-address</ipv4-capability>
      <ipv4-capability>destination-address</ipv4-capability>
     </generic-nsf-capabilities>
    </condition-capabilities>
    <action-capabilities>
     <ingress-action-capability>pass</ingress-action-capability>
     <ingress-action-capability>drop</ingress-action-capability>
  <ingress-action-capability>alert</ingress-action-capability>
     <ingress-action-capability>mirror</ingress-action-capability>
     <egress-action-capability>pass</egress-action-capability>
     <egress-action-capability>drop</egress-action-capability>
  <egress-action-capability>alert</egress-action-capability>
     <egress-action-capability>mirror</egress-action-capability>
    </action-capabilities>
   </nsf>

      Figure 6: Configuration XML for the Capabilities Registration of
                  a Time-based Firewall in an IPv4 Network

   Figure 6 shows the configuration XML for the capabilities
   registration of a time-based firewall as an NSF in an IPv4 network.
   Its capabilities are as follows.

   1.  The name of the NSF is time_based_firewall.

   2.  The NSF can execute the security policy rule according to
       absolute time and periodic time.

   3.  The NSF can inspect a protocol (Next-Header), an exact the IPv4
       address, protocol header field, flow
       direction, source address(es), and a range of IPv4 addresses for IPv4 packets. destination address(es).

   4.  The NSF can control whether the packets are allowed to pass,
       drop, or alert. mirror.

   <nsf xmlns="urn:ietf:params:xml:ns:yang:ietf-i2nsf-capability">
    <nsf-name>time_based_firewall</nsf-name>
    <event-capabilities>
      <time-capabilities>absolute-time</time-capabilities>
      <time-capabilities>periodic-time</time-capabilities>
    </event-capabilities>
    <condition-capabilities>
     <generic-nsf-capabilities>
   <ipv6-capability>ipv6-next-header</ipv6-capability>
   <ipv6-capability>prefix-ipv6-address-flow-direction</ipv6-capability>
   <ipv6-capability>prefix-ipv6-address</ipv6-capability>
   <ipv6-capability>range-ipv6-address-flow-direction</ipv6-capability>
   <ipv6-capability>range-ipv6-address</ipv6-capability>
      <ipv6-capability>next-header</ipv6-capability>
      <ipv6-capability>flow-direction</ipv6-capability>
      <ipv6-capability>source-address</ipv6-capability>
      <ipv6-capability>destination-address</ipv6-capability>
     </generic-nsf-capabilities>
    </condition-capabilities>
    <action-capabilities>
     <ingress-action-capability>pass</ingress-action-capability>
     <ingress-action-capability>drop</ingress-action-capability>
  <ingress-action-capability>alert</ingress-action-capability>
     <ingress-action-capability>mirror</ingress-action-capability>
     <egress-action-capability>pass</egress-action-capability>
     <egress-action-capability>drop</egress-action-capability>
  <egress-action-capability>alert</egress-action-capability>
     <egress-action-capability>mirror</egress-action-capability>
    </action-capabilities>
   </nsf>

      Figure 7: Configuration XML for the Capabilities Registration of
                  a Time-based Firewall in an IPv6 Network

   In addition, Figure 7 shows the configuration XML for the
   capabilities registration of a time-based firewall as an NSF in an
   IPv6 network.  Its capabilities are as follows.

   1.  The name of the NSF is time_based_firewall.

   2.  The NSF can execute the security policy rule according to
       absolute time and periodic time.

   3.  The NSF can inspect a protocol (Next-Header), an exact the IPv6
       address, protocol header field, flow
       direction, source address(es), and a range of IPv6 addresses for IPv6 packets. destination address(es).

   4.  The NSF can control whether the packets are allowed to pass,
       drop, or alert. mirror.

A.3.  Example 3: Registration for the Capabilities of a Web Filter

   This section shows a configuration example for the capabilities
   registration of a web filter.

   <nsf xmlns="urn:ietf:params:xml:ns:yang:ietf-i2nsf-capability">
    <nsf-name>web_filter</nsf-name>
    <condition-capabilities>
     <advanced-nsf-capabilities>
      <url-capability>user-defined</url-capability>
     </advanced-nsf-capabilities>
    </condition-capabilities>
    <action-capabilities>
     <ingress-action-capability>pass</ingress-action-capability>
     <ingress-action-capability>drop</ingress-action-capability>
     <ingress-action-capability>alert</ingress-action-capability>
     <ingress-action-capability>mirror</ingress-action-capability>
     <egress-action-capability>pass</egress-action-capability>
     <egress-action-capability>drop</egress-action-capability>
     <egress-action-capability>alert</egress-action-capability>
     <egress-action-capability>mirror</egress-action-capability>
    </action-capabilities>
   </nsf>

      Figure 8: Configuration XML for the Capabilities Registration of
                                a Web Filter

   Figure 8 shows the configuration XML for the capabilities
   registration of a web filter as an NSF.  Its capabilities are as
   follows.

   1.  The name of the NSF is web_filter.

   2.  The NSF can inspect a URL matched from a user-defined URL
       Database. URL.  User
       can add the new URL to the database. specify their own URL.

   3.  The NSF can control whether the packets are allowed to pass,
       drop, or alert. mirror.

A.4.  Example 4: Registration for the Capabilities of a VoIP/VoLTE
      Filter

   This section shows a configuration example for the capabilities
   registration of a VoIP/VoLTE filter.

   <nsf xmlns="urn:ietf:params:xml:ns:yang:ietf-i2nsf-capability">
    <nsf-name>voip_volte_filter</nsf-name>
    <condition-capabilities>
     <advanced-nsf-capabilities>
      <voip-volte-capability>voip-volte-call-id</voip-volte-capability>
      <voip-volte-capability>call-id</voip-volte-capability>
     </advanced-nsf-capabilities>
    </condition-capabilities>
    <action-capabilities>
     <ingress-action-capability>pass</ingress-action-capability>
     <ingress-action-capability>drop</ingress-action-capability>
     <ingress-action-capability>alert</ingress-action-capability>
     <ingress-action-capability>mirror</ingress-action-capability>
     <egress-action-capability>pass</egress-action-capability>
     <egress-action-capability>drop</egress-action-capability>
     <egress-action-capability>alert</egress-action-capability>
     <egress-action-capability>mirror</egress-action-capability>
    </action-capabilities>
   </nsf>

      Figure 9: Configuration XML for the Capabilities Registration of
                            a VoIP/VoLTE Filter

   Figure 9 shows the configuration XML for the capabilities
   registration of a VoIP/VoLTE filter as an NSF.  Its capabilities are
   as follows.

   1.  The name of the NSF is voip_volte_filter.

   2.  The NSF can inspect a voice call id for VoIP/VoLTE packets.

   3.  The NSF can control whether the packets are allowed to pass,
       drop, or alert. mirror.

A.5.  Example 5: Registration for the Capabilities of a HTTP and HTTPS
      Flood Mitigator

   This section shows a configuration example for the capabilities
   registration of a HTTP and HTTPS flood mitigator.

   <nsf xmlns="urn:ietf:params:xml:ns:yang:ietf-i2nsf-capability">
    <nsf-name>http_and_https_flood_mitigation</nsf-name>
    <nsf-name>DDoS_mitigator</nsf-name>
    <condition-capabilities>
     <advanced-nsf-capabilities>
      <anti-ddos-capability>http-flood-action</anti-ddos-capability>
      <anti-ddos-capability>https-flood-action</anti-ddos-capability>
      <anti-ddos-capability>packet-rate</anti-ddos-capability>
      <anti-ddos-capability>byte-rate</anti-ddos-capability>
      <anti-ddos-capability>flow-rate</anti-ddos-capability>
     </advanced-nsf-capabilities>
    </condition-capabilities>
    <action-capabilities>
     <ingress-action-capability>pass</ingress-action-capability>
     <ingress-action-capability>drop</ingress-action-capability>
     <ingress-action-capability>alert</ingress-action-capability>
     <ingress-action-capability>mirror</ingress-action-capability>
     <egress-action-capability>pass</egress-action-capability>
     <egress-action-capability>drop</egress-action-capability>
     <egress-action-capability>alert</egress-action-capability>
     <egress-action-capability>mirror</egress-action-capability>
    </action-capabilities>
   </nsf>

     Figure 10: Configuration XML for the Capabilities Registration of
                      a HTTP and HTTPS Flood Mitigator

   Figure 10 shows the configuration XML for the capabilities
   registration of a HTTP and HTTPS flood mitigator as an NSF.  Its
   capabilities are as follows.

   1.  The name of the NSF is http_and_https_flood_mitigation. DDoS_mitigator.

   2.  The NSF can control detect the amount of packets for HTTP packet, flow, and HTTPS
       packets, which are routed to the NSF's IPv4 address or byte rate in
       the NSF's
       IPv6 address. network for potential DDoS Attack.

   3.  The NSF can control whether the packets are allowed to pass,
       drop, or alert. mirror.

Appendix B.  Acknowledgments

   This work was supported by Institute of Information & Communications
   Technology Planning & Evaluation (IITP) grant funded by the Korea
   MSIT (Ministry of Science and ICT) (R-20160222-002755, Cloud based
   Security Intelligence Technology Development for the Customized
   Security Service Provisioning).  This work was supported in part by
   the IITP grant funded by the MSIT (2020-0-00395, Standard Development
   of Blockchain based Network Management Automation Technology).

Appendix C.  Contributors

   This document is made by the group effort of I2NSF working group.
   Many people actively contributed to this document, such as Acee
   Lindem, Roman Danyliw, and Tom Petch.  The authors sincerely
   appreciate their contributions.

   The following are co-authors of this document:

   Patrick Lingga Department of Computer Science Electrical and Computer Engineering
   Sungkyunkwan University 2066 Seo-ro Jangan-gu Suwon, Gyeonggi-do
   16419 Republic of Korea EMail: patricklink@skku.edu

   Liang Xia Huawei 101 Software Avenue Nanjing, Jiangsu 210012 China
   EMail: Frank.Xialiang@huawei.com

   Cataldo Basile Politecnico di Torino Corso Duca degli Abruzzi, 34
   Torino, 10129 Italy EMail: cataldo.basile@polito.it

   John Strassner Huawei 2330 Central Expressway Santa Clara, CA 95050
   USA EMail: John.sc.Strassner@huawei.com

   Diego R.  Lopez Telefonica I+D Zurbaran, 12 Madrid, 28010 Spain
   Email: diego.r.lopez@telefonica.com

   Hyoungshick Kim Department of Computer Science and Engineering
   Sungkyunkwan University 2066 Seo-ro Jangan-gu Suwon, Gyeonggi-do
   16419 Republic of Korea EMail: hyoung@skku.edu

   Daeyoung Hyun Department of Computer Science and Engineering
   Sungkyunkwan University 2066 Seo-ro Jangan-gu Suwon, Gyeonggi-do
   16419 Republic of Korea EMail: dyhyun@skku.edu

   Dongjin Hong Department of Electronic, Electrical and Computer
   Engineering Sungkyunkwan University 2066 Seo-ro Jangan-gu Suwon,
   Gyeonggi-do 16419 Republic of Korea EMail: dong.jin@skku.edu

   Jung-Soo Park Electronics and Telecommunications Research Institute
   218 Gajeong-Ro, Yuseong-Gu Daejeon, 34129 Republic of Korea EMail:
   pjs@etri.re.kr

   Tae-Jin Ahn Korea Telecom 70 Yuseong-Ro, Yuseong-Gu Daejeon, 305-811
   Republic of Korea EMail: taejin.ahn@kt.com

   Se-Hui Lee Korea Telecom 70 Yuseong-Ro, Yuseong-Gu Daejeon, 305-811
   Republic of Korea EMail: sehuilee@kt.com

Authors' Addresses

   Susan Hares (editor)
   Huawei
   7453 Hickory Hill
   Saline, MI 48176
   USA
   United States of America

   Phone: +1-734-604-0332
   EMail:
   Email: shares@ndzh.com

   Jaehoon (Paul) Jeong (editor)
   Department of Computer Science and Engineering
   Sungkyunkwan University
   2066 Seobu-Ro, Jangan-Gu
   Suwon,
   Suwon
   Gyeonggi-Do
   16419
   Republic of Korea

   Phone: +82 31 299 4957
   Fax:   +82 31 290 7996
   EMail:
   Email: pauljeong@skku.edu
   URI:   http://iotlab.skku.edu/people-jaehoon-jeong.php

   Jinyong (Tim) Kim
   Department of Electronic, Electrical and Computer Engineering
   Sungkyunkwan University
   2066 Seobu-Ro, Jangan-Gu
   Suwon,
   Suwon
   Gyeonggi-Do
   16419
   Republic of Korea

   Phone: +82 10 8273 0930
   EMail:
   Email: timkim@skku.edu

   Robert Moskowitz
   HTT Consulting
   Oak Park, MI
   USA
   United States of America

   Phone: +1-248-968-9809
   EMail:
   Email: rgm@htt-consult.com
   Qiushi Lin
   Huawei
   Huawei Industrial Base
   Shenzhen,
   Shenzhen
   Guangdong 518129 518129,
   China

   EMail:

   Email: linqiushi@huawei.com