Network Working Group T. Graf Internet-Draft Swisscom Intended status: Informational 15 January 2022 Expires: 19 July 2022 Export of Segment Routing IPv6 Information in IP Flow Information Export (IPFIX) draft-tgraf-opsawg-ipfix-srv6-srh-00 Abstract This document introduces new IP Flow Information Export (IPFIX) code points to identify which traffic is being forwarded with which Segemnt Routing Header dimensions based on which SRv6 control plane protocol. 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 19 July 2022. Copyright Notice Copyright (c) 2022 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 carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Revised BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Revised BSD License. Graf Expires 19 July 2022 [Page 1] Internet-Draft IPFIX Segment Routing IPv6 Information January 2022 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. IPFIX Information Elements . . . . . . . . . . . . . . . . . 2 3. Use Cases . . . . . . . . . . . . . . . . . . . . . . . . . . 3 4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 3 5. Security Considerations . . . . . . . . . . . . . . . . . . . 5 6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 5 7. References . . . . . . . . . . . . . . . . . . . . . . . . . 5 7.1. Normative References . . . . . . . . . . . . . . . . . . 5 7.2. Informative References . . . . . . . . . . . . . . . . . 6 Appendix A. IPFIX Encoding Example . . . . . . . . . . . . . . . 7 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 9 1. Introduction A new type of Routing Extension Header called Segment Routing Header (SRH) is defined by [RFC8754] which is used for applying Segment Routing (SR) on the IPv6 data plane. Three routing protocol extensions, OSPFv3 Extensions [I-D.li-lsr-ospfv3-srv6-extensions], IS-IS Extensions [I-D.ietf-lsr-isis-srv6-extensions], BGP Prefix Segment Identifiers (Prefix-SIDs) [I-D.ietf-bess-srv6-services] and one Path Computation Element Communication Protocol (PCEP) Extension [I-D.ietf-pce-segment-routing-ipv6] have been defined to be able to propagate Segment Identifiers (SIDs) for the IPv6 data plane. This document defines five new IPFIX Information Elements (IEs) and two new subregistries within the "IPFIX Information Elements" registry [RFC7012] for the new SRH dimensions and routing protocol and PCEP extensions. 2. IPFIX Information Elements This section defines and describes the new IPFIX IEs. ipv6SRHFlags 8-bit flags defined in the SRH. ipv6SRHTag 16-bit tag field defined in the SRH that marks a packet as part of a class or group of packets sharing the same set of properties. ipv6SRHSegment 128-bit IPv6 address that represents an SRv6 segment. Graf Expires 19 July 2022 [Page 2] Internet-Draft IPFIX Segment Routing IPv6 Information January 2022 ipv6SRHSegmentList Ordered basicList of zero or more 128-bit IPv6 addresses in the SRH that represents the SRv6 segment list. The Segment List is encoded starting from the last segment of the SR Policy. ipv6SRHSegmentType Name of the routing protocol or PCEP extension from where last SRv6 segment has been learned from. 3. Use Cases By using ipv6SRHSegmentList(TBD5), ipv6SRHSegment1Type(TBD6) and forwardingStatus(89) it is possible to identify * how many packets are forwarded or dropped * if dropped, for which reasons, and * infer control plane protocol for the last segment * and the SRv6 segment list on every hop. 4. IANA Considerations This document requests IANA to create new IEs and two new subregistry called ""IPFIX IPv6 SRH Flags (TBD1)" and IPFIX IPv6 SRH Segment type (TBD5)" under the "IPFIX Information Elements" registry [RFC7012] available at [IANA-IPFIX] and assign the following code points. Graf Expires 19 July 2022 [Page 3] Internet-Draft IPFIX Segment Routing IPv6 Information January 2022 +--------+-------------------+------------+-----------+-------------+ | Element| Name | Abstract | Data Type | Reference | | ID | | Data Type | Semantics | | +--------+-------------------+------------+-------------------------+ | TBD1 | ipv6SRHFlag | unsigned8 | flags | [RFC-to-be],| | | | | | RFC8754 | +--------+-------------------+------------+-------------------------+ | TBD2 | ipv6SRHTag | unsigned16 | identifier| [RFC-to-be],| | | | | | RFC8754 | +--------+-------------------+------------+-------------------------+ | TBD3 | ipv6SRHSegment | ipv6address| default | [RFC-to-be],| | | | | | RFC8754 | +--------+-------------------+------------+-------------------------+ | TBD4 | ipv6SRHSegmentList| basiclist | list | [RFC-to-be],| | | | | | RFC8754 | +--------+-------------------+------------+-------------------------+ | TBD5 | ipv6SRHSegmentType| unsigned8 | identifier| [RFC-to-be] | +--------+-------------------+------------+-------------------------+ Table 1: Creates IEs in the "IPFIX Information Elements" registry +--------+-------------------+--------------------------------------+ | Value | Description | Reference | +--------+-------------------+--------------------------------------+ | 0-7 | Unassigned | | +--------+-------------------+--------------------------------------+ Table 2: Creates "IPFIX IPv6 SRH Flags (TBD1)" subregistry Graf Expires 19 July 2022 [Page 4] Internet-Draft IPFIX Segment Routing IPv6 Information January 2022 +-------+--------------------+--------------------------------------+ | Value | Description | Reference | +-------+--------------------+--------------------------------------+ | TBD6 | Unknown | [RFC-to-be] | | | | | +-------+--------------------+--------------------------------------+ | TBD7 | Path Computation | [RFC-to-be], | | | Element | draft-ietf-pce-segment-routing-ipv6 | +-------+--------------------+--------------------------------------+ | TBD8 | OSPFv3 | [RFC-to-be], | | | Segment Routing | draft-li-ospf-ospfv3-srv6-extensions | +-------+--------------------+--------------------------------------+ | TBD9 | IS-IS | [RFC-to-be] | | | Segment Routing | draft-ietf-lsr-isis-srv6-extensions | +-------+--------------------+--------------------------------------+ | TBD10 | BGP Segment | [RFC-to-be], | | | Routing Prefix-SID | draft-ietf-bess-srv6-services | +-------+--------------------+--------------------------------------+ Table 3: Creates "IPFIX IPv6 SRH Segment type (TBD5)" subregistry Note to the RFC-Editor: * Please replace TBD1 - TBD10 with the values allocated by IANA * Please replace the [RFC-to-be] with the RFC number assigned to this document 5. Security Considerations There exists no significant extra security considerations regarding the allocation of these new IPFIX IEs compared to [RFC7012]. 6. Acknowledgements TBD 7. References 7.1. Normative References [RFC6313] Claise, B., Dhandapani, G., Aitken, P., and S. Yates, "Export of Structured Data in IP Flow Information Export (IPFIX)", RFC 6313, DOI 10.17487/RFC6313, July 2011, . Graf Expires 19 July 2022 [Page 5] Internet-Draft IPFIX Segment Routing IPv6 Information January 2022 [RFC7012] Claise, B., Ed. and B. Trammell, Ed., "Information Model for IP Flow Information Export (IPFIX)", RFC 7012, DOI 10.17487/RFC7012, September 2013, . 7.2. Informative References [I-D.ietf-bess-srv6-services] Dawra, G., Filsfils, C., Talaulikar, K., Raszuk, R., Decraene, B., Zhuang, S., and J. Rabadan, "SRv6 BGP based Overlay Services", Work in Progress, Internet-Draft, draft-ietf-bess-srv6-services-08, 10 November 2021, . [I-D.ietf-lsr-isis-srv6-extensions] Psenak, P., Filsfils, C., Bashandy, A., Decraene, B., and Z. Hu, "IS-IS Extensions to Support Segment Routing over IPv6 Dataplane", Work in Progress, Internet-Draft, draft- ietf-lsr-isis-srv6-extensions-18, 20 October 2021, . [I-D.ietf-pce-segment-routing-ipv6] Li, C., Negi, M., Sivabalan, S., Koldychev, M., Kaladharan, P., and Y. Zhu, "PCEP Extensions for Segment Routing leveraging the IPv6 data plane", Work in Progress, Internet-Draft, draft-ietf-pce-segment-routing-ipv6-11, 10 January 2022, . [I-D.li-lsr-ospfv3-srv6-extensions] Li, Z., Hu, Z., Cheng, D., Talaulikar, K., and P. Psenak, "OSPFv3 Extensions for SRv6", Work in Progress, Internet- Draft, draft-li-lsr-ospfv3-srv6-extensions-00, 15 January 2020, . [IANA-IPFIX] "IANA, "IP Flow Information Export (IPFIX) Entities"", . [RFC8754] Filsfils, C., Ed., Dukes, D., Ed., Previdi, S., Leddy, J., Matsushima, S., and D. Voyer, "IPv6 Segment Routing Header (SRH)", RFC 8754, DOI 10.17487/RFC8754, March 2020, . Graf Expires 19 July 2022 [Page 6] Internet-Draft IPFIX Segment Routing IPv6 Information January 2022 Appendix A. IPFIX Encoding Example In this section an example is provided to show the encoding format for the newly introduced IEs. +-----+------+-----+--------+---------------------------------------| | SRH | SRH | SRH | Segment| Segment List | | Nr | Flags| Tag | Type | | +-----+------+-----+--------+---------------------------------------+ | 1 | 0 | 123 | IS-IS | 2001:db8::1, 2001:db8::2, 2001:db8::3 | +-----+------+-----+--------+---------------------------------------+ | 2 | 0 | 456 | IS-IS | 2001:db8::4, 2001:db8::5 | +-----+------+-----+--------+---------------------------------------+ | 3 | 0 | 789 | IS-IS | 2001:db8::6 | +-----+------+-----+--------+---------------------------------------+ Table 4: 3 observed SRH headers and their routing protocol A.1. Template Record 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | SET ID = 2 | Length = 41 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Template ID = 256 | Field Count = 4 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0| ipv6SRHFlags = TBD2 | Field Length = 1 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0| ipv6SRHTag = TBD3 | Field Length = 2 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0| ipv6SRHSegmentType = TBD6 | Field Length = 1 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0| ipv6SRHSegment = TBD4 | Field Length = 16 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0| ipv6SRHSegmentList = TBD5 | Field Length = 0xFFFF | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Table 4: Template Record Encoding Format In this example, the Template ID is 256, which will be used in the Data Record. The field length for ipv6SRHSegmentList is 0xFFFF, which means the length of this IE is variable, and the actual length of this IE is indicated by the List Length field in the basicList format as per [RFC6313]. Graf Expires 19 July 2022 [Page 7] Internet-Draft IPFIX Segment Routing IPv6 Information January 2022 A.2. Data Set The data set is represented as follows: 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | SET ID = 256 | Length = 136 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ipv6SRHFlags | ipv6SRHTag = 123 | ipv6SRHSegment| | = 0 | | Type = TBD9 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | 255 | List Length = 53 |semantic= | | | |ordered | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ipv6SRHSegment = TBD4 | Field Length = 16 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Segment List[0] = 2001:db8::1 (16 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Segment List[1] = 2001:db8::2 (16 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Segment List[2] = 2001:db8::3 (16 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ipv6SRHFlags | ipv6SRHTag = 456 | ipv6SRHSegment| | = 0 | | Type = TBD9 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | 255 | List Length = 37 |semantic= | | | |ordered | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ipv6SRHSegment = TBD4 | Field Length = 16 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Segment List[0] = 2001:db8::4 (16 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Segment List[1] = 2001:db8::5 (16 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ipv6SRHFlags | ipv6SRHTag = 789 | ipv6SRHSegment| | = 0 | | Type = TBD9 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | 255 | List Length = 21 |semantic= | | | |ordered | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ipv6SRHSegment = TBD4 | Field Length = 16 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Segment List[0] = 2001:db8::6 (16 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Table 5: Data Set Encoding Format Graf Expires 19 July 2022 [Page 8] Internet-Draft IPFIX Segment Routing IPv6 Information January 2022 Author's Address Thomas Graf Swisscom Binzring 17 CH-8045 Zurich Switzerland Email: thomas.graf@swisscom.com Graf Expires 19 July 2022 [Page 9]