draft-ietf-manet-dlep-lid-extension-04.txt   draft-ietf-manet-dlep-lid-extension-05.txt 
Mobile Ad hoc Networks Working Group R. Taylor Mobile Ad hoc Networks Working Group R. Taylor
Internet-Draft Airbus Defence & Space Internet-Draft Airbus Defence & Space
Intended status: Standards Track S. Ratliff Intended status: Standards Track S. Ratliff
Expires: February 24, 2019 VT iDirect Expires: January 26, 2020 VT iDirect
August 23, 2018 July 25, 2019
DLEP Link Identifier Extension DLEP Link Identifier Extension
draft-ietf-manet-dlep-lid-extension-04 draft-ietf-manet-dlep-lid-extension-05
Abstract Abstract
There exists a class of modems that would benefit from supporting the The Dynamic Link Exchange Protocol (DLEP) [RFC8175] describes a
Dynamic Link Exchange Protocol (DLEP) [RFC8175] but do not present a protocol for modems to advertise the status of wireless links between
single Layer 2 network domain as required by DLEP. Such devices may reachable destinations to attached routers. The core specification
be: of the protocol assumes that every modem in the radio network has an
attached DLEP router, and requires that the MAC address of the DLEP
o Modems that maintain a varying link to some upstream backbone interface on the attached router be used to identify the destination
network infrastructure, where the ability to announce link state in the network, for purposes of reporting the state and quality of
and DLEP metrics is desired, but the concept of a DLEP destination the link to that destination.
router for the backbone does not apply. Examples of such devices
can include LTE modems, IEEE 802.11 stations not in ad-hoc mode,
and some satellite terminals.
o Modems that provide Layer 3 wide area network connectivity between
devices, where remote DLEP destinations do exist, but are not
directly reachable by MAC address, such as modems that contain
embedded routing functionality.
This document introduces an optional extension to the core DLEP
specification, allowing DLEP to be used between routers and modems
that operate in this way.
Note:
o This document is intended as an extension to the core DLEP This document describes a DLEP Extension allowing modems that do not
specification, and readers are expected to be fully conversant meet the strict requirement above to use DLEP to describe link
with the operation of core DLEP. availability and quality to one or more destinations reachable beyond
a device on the Layer 2 domain.
Status of This Memo Status of This Memo
This Internet-Draft is submitted in full conformance with the This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79. provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
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Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
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time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on February 24, 2019. This Internet-Draft will expire on January 26, 2020.
Copyright Notice Copyright Notice
Copyright (c) 2018 IETF Trust and the persons identified as the Copyright (c) 2019 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
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described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Requirements . . . . . . . . . . . . . . . . . . . . . . 3 1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
2. Operation . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.2. Applicability . . . . . . . . . . . . . . . . . . . . . . 3
2.1. Identifier Restrictions . . . . . . . . . . . . . . . . . 4 1.3. Requirements . . . . . . . . . . . . . . . . . . . . . . 3
2. Operation . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.1. Identifier Restrictions . . . . . . . . . . . . . . . . . 5
2.2. Negotiation . . . . . . . . . . . . . . . . . . . . . . . 5 2.2. Negotiation . . . . . . . . . . . . . . . . . . . . . . . 5
3. New Data Items . . . . . . . . . . . . . . . . . . . . . . . 5 3. New Data Items . . . . . . . . . . . . . . . . . . . . . . . 6
3.1. Link Identifier Length Data Item . . . . . . . . . . . . 5 3.1. Link Identifier Length Data Item . . . . . . . . . . . . 6
3.2. Link Identifier Data Item . . . . . . . . . . . . . . . . 6 3.2. Link Identifier Data Item . . . . . . . . . . . . . . . . 6
4. Security Considerations . . . . . . . . . . . . . . . . . . . 6 4. Security Considerations . . . . . . . . . . . . . . . . . . . 7
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7
6. References . . . . . . . . . . . . . . . . . . . . . . . . . 7 6. Normative References . . . . . . . . . . . . . . . . . . . . 7
6.1. Normative References . . . . . . . . . . . . . . . . . . 7 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 8
6.2. Informative References . . . . . . . . . . . . . . . . . 7
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 7
1. Introduction 1. Introduction
The Dynamic Link Exchange Protocol (DLEP) [RFC8175] describes a The Dynamic Link Exchange Protocol (DLEP) [RFC8175] describes a
protocol for modems to advertise the status of wireless links between protocol for modems to advertise the status of wireless links between
reachable destinations to attached routers. The core specification reachable destinations to attached routers. The core specification
of the protocol assumes that every modem in the radio network has an of the protocol assumes that every modem in the radio network has an
attached DLEP router, and requires that the MAC address of the DLEP attached DLEP router, and requires that the MAC address of the DLEP
interface on the attached router is used to identify the destination interface on the attached router be used to identify the destination
in the network for purposes of reporting the state and quality of the in the network, for purposes of reporting the state and quality of
link to that destination. the link to that destination.
This document describes a DLEP Extension allowing modems that do not This document describes a DLEP Extension allowing modems that do not
meet the strict requirement that DLEP must be implemented on a single meet the strict requirement above to use DLEP to describe link
Layer 2 domain to use DLEP to describe link availability and quality availability and quality to one or more destinations reachable beyond
to one or more destinations reachable beyond a local or remote device a device on the Layer 2 domain.
on the Layer 2 domain. A router can use this knowledge to influence
any routing or flow-control decisions regarding traffic to this As with core DLEP, a router can use this knowledge to influence any
routing or flow-control decisions regarding traffic to this
destination, understanding that such traffic flows via Layer 3. destination, understanding that such traffic flows via Layer 3.
A Layer 3 destination may be an attached DLEP router, in the case of 1.1. Terminology
a modem that provides Layer 3 wide area network connectivity between
devices, or a logical destination that describes a set of attached
subnets, when referring to some upstream backbone network
infrastructure.
1.1. Requirements Local Layer 2 domain: The Layer 2 domain that links the router and
modem participants of the current DLEP session.
Layer 3 DLEP Destination: A DLEP Destination that is not directly
addressable within the local Layer 2 domain, but is reachable via
a node addressable within the local Layer 2 domain.
Gateway Node: The last device with a MAC address reachable in the
local Layer 2 domain on the path from the DLEP router participant,
towards the Layer 3 DLEP Destination. This device is commonly the
DLEP peer modem but could be another DLEP Destination in the Layer
2 domain.
1.2. Applicability
This extension was designed primarily to address the following use
cases:
1. A radio system that does not operate in Layer 2 bridge mode, but
instead provides Layer 3 connectivity between destinations, often
using its own embedded Layer 3 routing function.
2. A point-to-multipoint tunnel system, such as an SD-WAN
deployment, where the tunnel provider acts as a modem, having
knowledge of the characteristics of the underlay network, and
providing that information as availability and metrics between
tunnel endpoints in the overlay network.
3. A modem that provides connectivity to a remote wide-area network
via a wireless link, but the concept of a Layer 2 reachable
remote router does not apply. An example of such a modem would
be an LTE device or 802.11 station that provides variable
connectivity to the Internet.
This list of use-cases is not exhaustive, and this extension may well
be applicable to future, currently unforeseen, use-cases.
1.3. Requirements
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
document are to be interpreted as described in BCP 14, RFC 2119. "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.
2. Operation 2. Operation
To refer to a Layer 3 DLEP Destination, the DLEP session participant To refer to a Layer 3 DLEP Destination, the DLEP session participant
adds a Link Identifier Data Item (Section 3.2) to the relevant adds a Link Identifier Data Item (Section 3.2) to the relevant
Destination Message, and (as usual) includes a MAC Address Data Item. Destination Message, and (as usual) includes a MAC Address Data Item.
When paired with a Link Identifier Data Item, the MAC Address Data When paired with a Link Identifier Data Item, the MAC Address Data
Item MUST contain the MAC address of the last reachable node in the Item MUST contain the MAC address of the Gateway Node.
Layer 2 domain beyond which the Layer 3 DLEP Destination resides.
For example, if the over-the-air network is not a single Layer 2
domain, the MAC Address Data Item might be the address of the LAN-
side interface of the local modem. Alternatively, when used with
some kind of backbone infrastructure, the MAC Address Data Item would
be the address of the last device reachable on the local Layer 2
domain. However, how such remote destinations are discovered is
beyond the scope of this specification.
As only modems are initially aware of Layer 3 DLEP Destinations, Link As only modems are initially aware of Layer 3 DLEP Destinations, Link
Identifier Data Items referring to a new link MUST first appear in a Identifier Data Items referring to a new link MUST first appear in a
DLEP Destination Up Message from the modem to the router. Once a DLEP Destination Up Message from the modem to the router. Once a
link has been identified in this way, Link Identifier Data Items MAY link has been identified in this way, Link Identifier Data Items may
be used by either DLEP participant during the lifetime of a DLEP be used by either DLEP participant during the lifetime of a DLEP
session. Because of this, a router MUST NOT send a DLEP Destination session. Because of this, a router MUST NOT send a DLEP Destination
Announce Message containing a Link Identifier Data Item referring to Announce Message containing a Link Identifier Data Item referring to
a link that has not been mentioned in a prior DLEP Destination Up a link that has not been mentioned in a prior DLEP Destination Up
Message. Message. If a modem receives such a message, it MUST terminate the
session by issuing a Session Termination Message containing a Status
Data Item with status code set to 131 'Invalid Destination' and
transition to the Session Termination state.
Because the MAC Address associated with any DLEP Destination Message Because the MAC Address associated with any DLEP Destination Message
containing a Link Identifier Data Item is not the Layer 2 address of containing a Link Identifier Data Item is not the Layer 2 address of
the destination, all DLEP Destination Up Messages MUST contain Layer the final destination, all DLEP Destination Up Messages containing a
3 information. In the case of modems that provide Layer 3 wide area Link Identifier Data Item MUST contain Layer 3 information. In the
network connectivity between devices, this means one or more IPv4 or case of modems that provide Layer 3 wide area network connectivity
IPv6 Address Data Items providing the Layer 3 address of the between devices, this means one or more IPv4 or IPv6 Address Data
destination. When referring to some upstream backbone network Items providing the Layer 3 address of the final destination. When
infrastructure, this means one or more IPv4 or IPv6 Attached Subnet referring to some upstream backbone network infrastructure, this
Data Items, for example: '0.0.0.0/0' or '::/0'. This allows the DLEP means one or more IPv4 or IPv6 Attached Subnet Data Items, for
peer router to understand the properties of the link to those routes. example: '0.0.0.0/0' or '::/0'. This allows the DLEP peer router to
understand the properties of the link to those routes.
When the DLEP peer router wishes to forward packets to the Layer 3 When the DLEP peer router wishes to route packets to the Layer 3 DLEP
destination or subnet, the MAC address associated with the link MUST Destination, the MAC address associated with the Gateway Node MUST be
be used as the Layer 2 destination of the packet if it wishes to use used as the Layer 2 destination of the packet, if it wishes to use
the modem network to forward the packet. the modem network to forward the packet.
As most mainstream routers expect to populate their routing As routers populate their routing information base with the IP
information base with the IP address of the next router towards a address of the next hop router towards a destination, implementations
destination, implementations supporting this extension SHOULD supporting this extension SHOULD announce at least one valid IPv4 or
announce one or more valid IPv4 or IPv6 addresses of the last IPv6 addresses of the Gateway Node, this removes the need for the
reachable Layer 2 device, i.e. the device with the corresponding MAC router to use an additional IP address resolution protocol before
Address. adding the route to its routing information base.
If the last reachable Layer 2 device is not the DLEP peer modem, then
the modem SHOULD announce a DLEP Destination with the required MAC
Address without including a Link Identifier Data Item.
2.1. Identifier Restrictions 2.1. Identifier Restrictions
A Link Identifier is by default 4 octets in length. If a modem A Link Identifier is by default 4 octets in length. If a modem
wishes to use a Link Identifier of a different length, it MUST be wishes to use a Link Identifier of a different length, it MUST be
announced using the Link Identifier Length Data Item (Section 3.1) announced using the Link Identifier Length Data Item (Section 3.1)
contained in the DLEP Session Initialization Response message sent by contained in the DLEP Session Initialization Response message sent by
the modem to the router. the modem to the router.
During the lifetime of a DLEP session, the length of Link Identifiers During the lifetime of a DLEP session, the length of Link Identifiers
MUST remain constant, i.e. the Length field of the Link Identifier MUST remain constant, i.e. the Length field of the Link Identifier
Data Item MUST NOT differ between destinations. Data Item MUST NOT differ between destinations.
The method for generating Link Identifiers is a modem implementation The method for generating Link Identifiers is a modem implementation
matter and out of scope of this document. Routers MUST NOT make any matter and out of scope of this document. Routers must not make any
assumptions about the meaning of Link Identifiers, or how Link assumptions about the meaning of Link Identifiers, or how Link
Identifiers are generated. Identifiers are generated.
Within a single DLEP session, all Link Identifiers MUST be unique per Within a single DLEP session, all Link Identifiers MUST be unique per
MAC Address. This means that a Layer 3 DLEP Destination is uniquely MAC Address. This means that a Layer 3 DLEP Destination is uniquely
identified by the pair: {MAC Address,Link Identifier}. identified by the pair: {MAC Address,Link Identifier}.
Link Identifiers MUST NOT be reused, i.e. a {MAC Address,Link Link Identifiers MUST NOT be reused, i.e. a {MAC Address,Link
Identifier} pair that has been used to refer to one DLEP Destination Identifier} pair that has been used to refer to one Layer 3 DLEP
MUST NOT be recycled to refer to a different destination within the Destination MUST NOT be recycled to refer to a different destination
lifetime of a single DLEP session. within the lifetime of a single DLEP session.
2.2. Negotiation 2.2. Negotiation
To use this extension, as with all DLEP extensions, the extension To use this extension, as with all DLEP extensions, the extension
MUST be announced during DLEP session initialization. A router MUST be announced during DLEP session initialization. A router
advertises support by including the value 'Link Identifiers' (TBD1), advertises support by including the value 'Link Identifiers', TBD1
Section 5, in the Extension Data Item within the Session (Section 5), in the Extension Data Item within the Session
Initialization Message. A modem advertises support by including the Initialization Message. A modem advertises support by including the
value 'Link Identifiers' (TBD1) in the Extension Data Item within the value 'Link Identifiers' in the Extension Data Item within the
Session Initialization Response Message. If both DLEP peers Session Initialization Response Message. If both DLEP peers
advertise support for this extension then the Link Identifier Data advertise support for this extension then Link Identifier Data Items
Item MAY be used. can be included in DLEP Messages.
If a modem requires support for this extension in order to describe If a modem requires support for this extension in order to describe
destinations, and the router does not advertise support, then the destinations, and the router does not advertise support, then the
modem MUST NOT include a Link Identifier Data Item in any DLEP modem MUST NOT include a Link Identifier Data Item in any DLEP
Message. However, the modem SHOULD NOT immediately terminate the Message. However, the modem SHOULD NOT immediately terminate the
DLEP session, rather it SHOULD use session-wide DLEP Data Items to DLEP session, rather it SHOULD use a combination of DLEP Session
announce general information about all reachable destinations via the Messages and DLEP Attached Subnet Data Items to provide general
modem. By doing this, a modem allows a router not supporting this information.
extension to at least make a best guess at the state of any reachable
network. A modem MUST NOT attempt to re-use the MAC Address Data
Item to perform some kind of sleight-of-hand, assuming that the
router will notice the DLEP Peer Type of the modem is special in some
way.
3. New Data Items 3. New Data Items
This extension introduces two new DLEP Data Items: the Link This extension introduces two new DLEP Data Items: the Link
Identifier Data Item (Section 3.2) used to identify a Layer 3 link at Identifier Data Item (Section 3.2) used to identify a Layer 3 link at
or beyond a destination, and the Link Identifier Length Data Item or beyond a destination, and the Link Identifier Length Data Item
(Section 3.1) used to announce the length of Link Identifiers at (Section 3.1) used to announce the length of Link Identifiers at
session initialization. session initialization.
3.1. Link Identifier Length Data Item 3.1. Link Identifier Length Data Item
The Link Identifier Length Data Item is used by a DLEP modem The Link Identifier Length Data Item is used by a DLEP modem
implementation to specify the length of Link Identifier Data Items. implementation to specify the length of Link Identifier Data Items.
It MUST be used if the specified length is not the default value of 4 It MUST be used during Session Initialization, contained in a Session
octets. Initialization Response Message, if the specified length is not the
default value of 4 octets.
The Link Identifier Length Data Item MAY be used during Session
Initialization, contained in a Session Initialization Response
Message.
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Data Item Type | Length | | Data Item Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Identifier Length | | Link Identifier Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Data Item Type: TBD2, Section 5 Data Item Type: TBD2 (Section 5)
Length: 2 Length: 2
Link Identifier Length: The length, in octets, of Link Identifiers Link Identifier Length: The length, in octets, of Link Identifiers
used by the DLEP modem for this session. used by the DLEP modem for this session.
A Link Identifier Length Data Item that specifies a Link Identifier
Length of 4 octets (the default) is valid, even if it has no effect.
3.2. Link Identifier Data Item 3.2. Link Identifier Data Item
The Link Identifier Data Item MAY be used wherever a MAC Address Data The Link Identifier Data Item MAY be used wherever a MAC Address Data
Item is defined as usable in core DLEP. Item is defined as usable in core DLEP.
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Data Item Type | Length | | Data Item Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Identifier... : | Link Identifier... :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Data Item Type: TBD3, Section 5 Data Item Type: TBD3 (Section 5)
Length: The length of the Data Item, by default 4, but may be Length: The length of the Data Item, by default 4, but may be
different if a Link Identifier Length Data Item (Section 3.1) has different if a Link Identifier Length Data Item (Section 3.1) has
been announced during session initialization. been announced during session initialization.
Link Identifier: The unique identifier of the Layer 3 destination. Link Identifier: The unique identifier of the Layer 3 DLEP
This Link Identifier has no implicit meaning and is only used to Destination. This Link Identifier has no implicit meaning and is
discriminate between multiple links. only used to discriminate between multiple links.
4. Security Considerations 4. Security Considerations
As an extension to the core DLEP protocol, the security As an extension to the core DLEP protocol, the security
considerations of that protocol apply to this extension. This considerations of that protocol apply to this extension. This
extension adds no additional security mechanisms or features. extension adds no additional security mechanisms or features.
None of the features introduced by this extension require extra None of the features introduced by this extension require extra
consideration by an implementation. consideration by an implementation.
skipping to change at page 7, line 19 skipping to change at page 7, line 35
o Assign a new DLEP Extensions Registry value (TBD1) from the o Assign a new DLEP Extensions Registry value (TBD1) from the
Specification Required section, named "Link Identifiers". Specification Required section, named "Link Identifiers".
o Assign a new DLEP Data Item Type Values Registry value (TBD2) from o Assign a new DLEP Data Item Type Values Registry value (TBD2) from
the Specification Required section, named "Link Identifier the Specification Required section, named "Link Identifier
Length". Length".
o Assign a new DLEP Data Item Type Values Registry value (TBD3) from o Assign a new DLEP Data Item Type Values Registry value (TBD3) from
the Specification Required section, named "Link Identifier". the Specification Required section, named "Link Identifier".
6. References 6. Normative References
6.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997, DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>. <https://www.rfc-editor.org/info/rfc2119>.
[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>.
[RFC8175] Ratliff, S., Jury, S., Satterwhite, D., Taylor, R., and B. [RFC8175] Ratliff, S., Jury, S., Satterwhite, D., Taylor, R., and B.
Berry, "Dynamic Link Exchange Protocol (DLEP)", RFC 8175, Berry, "Dynamic Link Exchange Protocol (DLEP)", RFC 8175,
DOI 10.17487/RFC8175, June 2017, DOI 10.17487/RFC8175, June 2017,
<https://www.rfc-editor.org/info/rfc8175>. <https://www.rfc-editor.org/info/rfc8175>.
6.2. Informative References
[RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an
IANA Considerations Section in RFCs", RFC 5226,
DOI 10.17487/RFC5226, May 2008,
<https://www.rfc-editor.org/info/rfc5226>.
Authors' Addresses Authors' Addresses
Rick Taylor Rick Taylor
Airbus Defence & Space Airbus Defence & Space
Quadrant House Quadrant House
Celtic Springs Celtic Springs
Coedkernew Coedkernew
Newport NP10 8FZ Newport NP10 8FZ
UK UK
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