--- 1/draft-ietf-detnet-ip-over-tsn-03.txt 2020-11-02 09:13:49.851638966 -0800 +++ 2/draft-ietf-detnet-ip-over-tsn-04.txt 2020-11-02 09:13:49.879639670 -0800 @@ -1,44 +1,47 @@ DetNet B. Varga, Ed. Internet-Draft J. Farkas -Intended status: Standards Track Ericsson -Expires: December 10, 2020 A. Malis +Intended status: Informational Ericsson +Expires: May 6, 2021 A. Malis Malis Consulting S. Bryant Futurewei Technologies - June 8, 2020 + November 2, 2020 DetNet Data Plane: IP over IEEE 802.1 Time Sensitive Networking (TSN) - draft-ietf-detnet-ip-over-tsn-03 + draft-ietf-detnet-ip-over-tsn-04 Abstract This document specifies the Deterministic Networking IP data plane - when operating over a TSN sub-network. + when operating over a TSN sub-network. This document does not define + new procedures or processes. Whenever this document makes + requirements statements or recommendations, these are taken from + normative text in the referenced RFCs. Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at https://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." - This Internet-Draft will expire on December 10, 2020. + This Internet-Draft will expire on May 6, 2021. Copyright Notice Copyright (c) 2020 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents @@ -49,22 +52,22 @@ described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 2.1. Terms Used In This Document . . . . . . . . . . . . . . . 3 2.2. Abbreviations . . . . . . . . . . . . . . . . . . . . . . 3 2.3. Requirements Language . . . . . . . . . . . . . . . . . . 3 3. DetNet IP Data Plane Overview . . . . . . . . . . . . . . . . 3 - 4. DetNet IP Flows over an IEEE 802.1 TSN sub-network . . . . 5 - 4.1. Functions for DetNet Flow to TSN Stream Mapping . . . . . 6 + 4. DetNet IP Flows over an IEEE 802.1 TSN sub-network . . . . 4 + 4.1. Functions for DetNet Flow to TSN Stream Mapping . . . . . 5 4.2. TSN requirements of IP DetNet nodes . . . . . . . . . . . 6 4.3. Service protection within the TSN sub-network . . . . . . 8 4.4. Aggregation during DetNet flow to TSN Stream mapping . . 8 5. Management and Control Implications . . . . . . . . . . . . . 8 6. Security Considerations . . . . . . . . . . . . . . . . . . . 10 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10 8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 10 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 10 9.1. Normative references . . . . . . . . . . . . . . . . . . 10 9.2. Informative references . . . . . . . . . . . . . . . . . 11 @@ -143,86 +146,58 @@ masks, prefixes and ranges. IP tunnels may also be used to support flow aggregation. In these cases, it is expected that DetNet aware intermediate nodes will provide DetNet service assurance on the aggregate through resource allocation and congestion control mechanisms. Congestion protection, latency control and the resource allocation (queuing, policing, shaping) are supported using the underlying link / sub-net specific mechanisms. Service protections (packet replication and packet elimination functions) are not provided at the - DetNet layer end-to-end due the lack of a unified end-to-end + IP DetNet layer end-to-end due the lack of a unified end-to-end sequencing information that would be available for intermediate nodes. However, such service protection can be provided on a per underlying L2 link and sub-network basis. - Edge Transit Relay - Node Node Node - - +.........+ - <--:Svc Proxy:-- End to End Service -----------> - +-----....+ +..........+ - |IP | :Svc:<-- DetNet flow ---: Service :---> - +---+ +---+ +---------+ +---------+ - |Fwd| |Fwd| | Fwd | |Fwd| |Fwd| - +-.-+ +-.-+ +--.----.-+ +-.-+ +-.-+ - : / ,-----. \ : Link : : - .....+ +-[TSN Sub]-+ +........+ +..... - [Network] - `-----' - <------------- DetNet IP ------------- - - Figure 1: Part of a Simple DetNet (DN) Enabled IP Network using a TSN - sub-net - - Figure 1 illustrates an extract of a DetNet enabled IP network, that - uses a TSN sub-network as interconnection between two DetNet Nodes. - In this figure, an Edge Node sits at the boundary of the DetNet - domain and provide DetNet service proxies for the end applications by - initiating and terminating DetNet service for the application's IP - flows. Node and interface resources are allocated to ensure DetNet - service requirements. Dotted lines around the Service components of - the Edge and Relay Nodes indicate that they are DetNet service aware - but do not perform any DetNet service sub-layer function, e.g., PREOF - (Packet Replication, Elimination, and Ordering Functions). In this - example the Edge Node and the Transit Node are interconnected by a - TSN sub-network, being the primary focus of this document. - DetNet routers ensure that DetNet service requirements are met per hop by allocating local resources, both receive and transmit, and by mapping the service requirements of each flow to appropriate sub- network mechanisms. Such mappings are sub-network technology - specific. The mapping of DetNet IP flows to TSN streams and TSN - protection mechanisms are covered in Section 4. + specific. DetNet nodes interconnected by a TSN sub-network are the + primary focus of this document. The mapping of DetNet IP flows to + TSN streams and TSN protection mechanisms are covered in Section 4. 4. DetNet IP Flows over an IEEE 802.1 TSN sub-network This section covers how DetNet IP flows operate over an IEEE 802.1 - TSN sub-network. Figure 2 illustrates such a scenario, where two IP - (DetNet) nodes are interconnected by a TSN sub-network. Node-1 is - single homed and Node-2 is dual-homed to the TSN sub-network. + TSN sub-network. Figure 1 illustrates such a scenario, where two IP + (DetNet) nodes are interconnected by a TSN sub-network. Dotted lines + around the Service components of the IP (DetNet) Nodes indicate that + they are DetNet service aware but do not perform any DetNet service + sub-layer function. Node-1 is single homed and Node-2 is dual-homed + to the TSN sub-network. IP (DetNet) IP (DetNet) Node-1 Node-2 ............ ............ <--: Service :-- DetNet flow ---: Service :--> +----------+ +----------+ |Forwarding| |Forwarding| +--------.-+ <-TSN Str-> +-.-----.--+ \ ,-------. / / +----[ TSN-Sub ]---+ / [ Network ]--------+ `-------' <----------------- DetNet IP -----------------> - Figure 2: DetNet (DN) Enabled IP Network over a TSN sub-network + Figure 1: DetNet (DN) Enabled IP Network over a TSN sub-network The Time-Sensitive Networking (TSN) Task Group of the IEEE 802.1 Working Group have defined (and are defining) a number of amendments to IEEE 802.1Q [IEEE8021Q] that provide zero congestion loss and bounded latency in bridged networks. Furthermore, IEEE 802.1CB [IEEE8021CB] defines frame replication and elimination functions for reliability that should prove both compatible with and useful to DetNet networks. All these functions have to identify flows that require TSN treatment. @@ -266,34 +241,34 @@ Active Destination MAC and VLAN Stream identification can be used within a Talker to set flow identity or a Listener to recover the original addressing information. It can be used also in a TSN bridge that is providing translation as a proxy service for an End System. 4.2. TSN requirements of IP DetNet nodes This section covers required behavior of a TSN-aware DetNet node using a TSN sub-network. The implementation of TSN packet processing - functions MUST be compliant with the relevant IEEE 802.1 standards. + functions must be compliant with the relevant IEEE 802.1 standards. From the TSN sub-network perspective DetNet IP nodes are treated as Talker or Listener, that may be (1) TSN-unaware or (2) TSN-aware. In cases of TSN-unaware IP DetNet nodes the TSN relay nodes within the TSN sub-network must modify the Ethernet encapsulation of the DetNet IP flow (e.g., MAC translation, VLAN-ID setting, Sequence number addition, etc.) to allow proper TSN specific handling inside the sub-network. There are no requirements defined for TSN-unaware IP DetNet nodes in this document. IP (DetNet) nodes being TSN-aware can be treated as a combination of - a TSN-unaware Talker/Listener and a TSN-Relay, as shown in Figure 3. + a TSN-unaware Talker/Listener and a TSN-Relay, as shown in Figure 2. In such cases the IP (DetNet) node must provide the TSN sub-network specific Ethernet encapsulation over the link(s) towards the sub- network. IP (DetNet) Node <----------------------------------> ............ <--: Service :-- DetNet flow ------------------ @@ -304,41 +279,41 @@ | | | TSN function | Stream +-----.----+ +--.------.---.-+ \__________/ \ \______ \_________ TSN-unaware Talker / TSN-Bridge Listener Relay <----- TSN Sub-network ----- <------- TSN-aware Tlk/Lstn -------> - Figure 3: IP (DetNet) node with TSN functions + Figure 2: IP (DetNet) node with TSN functions - A TSN-aware IP (DetNet) node impementations MUST support the Stream + A TSN-aware IP (DetNet) node impementations must support the Stream Identification TSN component for recognizing flows. - A Stream identification component MUST be able to instantiate the + A Stream identification component must be able to instantiate the following functions (1) Active Destination MAC and VLAN Stream identification function, (2) IP Stream identification function, (3) Mask-and-Match Stream identification function and (4) the related managed objects in Clause 9 of IEEE 802.1CB [IEEE8021CB] and IEEE P802.1CBdb [IEEEP8021CBdb]. - A TSN-aware IP (DetNet) node implementations MUST support the + A TSN-aware IP (DetNet) node implementations must support the Sequencing function and the Sequence encode/decode function as defined in Clause 7.4 and 7.6 of IEEE 802.1CB [IEEE8021CB] if FRER is used inside the TSN sub-network. - The Sequence encode/decode function MUST support the Redundancy tag + The Sequence encode/decode function must support the Redundancy tag (R-TAG) format as per Clause 7.8 of IEEE 802.1CB [IEEE8021CB]. - A TSN-aware IP (DetNet) node implementations MUST support the Stream + A TSN-aware IP (DetNet) node implementations must support the Stream splitting function and the Individual recovery function as defined in Clause 7.7 and 7.5 of IEEE 802.1CB [IEEE8021CB] when the node is a replication or elimination point for FRER. 4.3. Service protection within the TSN sub-network TSN Streams supporting DetNet flows may use Frame Replication and Elimination for Redundancy (FRER) as defined in Clause 8. of IEEE 802.1CB [IEEE8021CB] based on the loss service requirements of the TSN Stream, which is derived from the DetNet service requirements of @@ -346,24 +321,24 @@ modified by the use of DetNet and follows IEEE 802.1CB [IEEE8021CB]. FRER function and the provided service recovery is available only within the TSN sub-network as the TSN Stream-ID and the TSN sequence number are not valid outside the sub-network. An IP (DetNet) node represents a L3 border and as such it terminates all related information elements encoded in the L2 frames. 4.4. Aggregation during DetNet flow to TSN Stream mapping - Implementations of this document SHALL use management and control + Implementations of this document shall use management and control information to map a DetNet flow to a TSN Stream. N:1 mapping - (aggregating DetNet flows in a single TSN Stream) SHALL be supported. - The management or control function that provisions flow mapping SHALL + (aggregating DetNet flows in a single TSN Stream) shall be supported. + The management or control function that provisions flow mapping shall ensure that adequate resources are allocated and configured to provide proper service requirements of the mapped flows. 5. Management and Control Implications DetNet flow and TSN Stream mapping related information are required only for TSN-aware IP (DetNet) nodes. From the Data Plane perspective there is no practical difference based on the origin of flow mapping related information (management plane or control plane). @@ -378,21 +353,25 @@ [IEEEP8021CBdb]. o Mapping between DetNet IP flow(s) (as flow identification defined in [I-D.ietf-detnet-ip], it is summarized in Section 5.1 of that document, and includes all wildcards, port ranges and the ability to ignore specific IP fields) and TSN Stream(s) (as stream identification information defined in [IEEE8021CB] and [IEEEP8021CBdb]). Note, that managed objects for TSN Stream identification can be found in [IEEEP8021CBcv]. - This information MUST be provisioned per DetNet flow. + This information must be provisioned per DetNet flow. + + Mappings between DetNet and TSN management and control planes are out + of scope of the document. Some of the challanges are highligthed + below. TSN-aware IP DetNet nodes are member of both the DetNet domain and the TSN sub-network. Within the TSN sub-network the TSN-aware IP (DetNet) node has a TSN-aware Talker/Listener role, so TSN specific management and control plane functionalities must be implemented. There are many similarities in the management plane techniques used in DetNet and TSN, but that is not the case for the control plane protocols. For example, RSVP-TE and MSRP behaves differently. Therefore management and control plane design is an important aspect of scenarios, where mapping between DetNet and TSN is required. @@ -466,73 +445,73 @@ The authors wish to thank Norman Finn, Lou Berger, Craig Gunther, Christophe Mangin and Jouni Korhonen for their various contributions to this work. 9. References 9.1. Normative references [I-D.ietf-detnet-ip] Varga, B., Farkas, J., Berger, L., Fedyk, D., and S. - Bryant, "DetNet Data Plane: IP", draft-ietf-detnet-ip-06 - (work in progress), April 2020. + Bryant, "DetNet Data Plane: IP", draft-ietf-detnet-ip-07 + (work in progress), July 2020. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017, . 9.2. Informative references [I-D.ietf-detnet-flow-information-model] Varga, B., Farkas, J., Cummings, R., Jiang, Y., and D. Fedyk, "DetNet Flow Information Model", draft-ietf-detnet- - flow-information-model-10 (work in progress), May 2020. + flow-information-model-11 (work in progress), October + 2020. [I-D.ietf-detnet-security] - Mizrahi, T. and E. Grossman, "Deterministic Networking - (DetNet) Security Considerations", draft-ietf-detnet- - security-10 (work in progress), May 2020. + Grossman, E., Mizrahi, T., and A. Hacker, "Deterministic + Networking (DetNet) Security Considerations", draft-ietf- + detnet-security-12 (work in progress), October 2020. [IEEE802.1AE-2018] IEEE Standards Association, "IEEE Std 802.1AE-2018 MAC Security (MACsec)", 2018, . [IEEE8021CB] - Finn, N., "Draft Standard for Local and metropolitan area - networks - Seamless Redundancy", IEEE P802.1CB - /D2.1 P802.1CB, December 2015, - . + IEEE 802.1, "Standard for Local and metropolitan area + networks - Frame Replication and Elimination for + Reliability (IEEE Std 802.1CB-2017)", 2017, + . [IEEE8021Q] IEEE 802.1, "Standard for Local and metropolitan area networks--Bridges and Bridged Networks (IEEE Std 802.1Q- - 2014)", 2014, . + 2018)", 2018, . [IEEEP8021CBcv] Kehrer, S., "FRER YANG Data Model and Management Information Base Module", IEEE P802.1CBcv - /D0.3 P802.1CBcv, May 2020, - . + /D0.4 P802.1CBcv, August 2020, + . [IEEEP8021CBdb] Mangin, C., "Extended Stream identification functions", - IEEE P802.1CBdb /D0.2 P802.1CBdb, August 2019, - . + IEEE P802.1CBdb /D1.0 P802.1CBdb, September 2020, + . [RFC8655] Finn, N., Thubert, P., Varga, B., and J. Farkas, "Deterministic Networking Architecture", RFC 8655, DOI 10.17487/RFC8655, October 2019, . Authors' Addresses Balazs Varga (editor) Ericsson