SPRING D. Patki Internet-Draft Cisco Systems, Inc. Intended status: Standards Track June 24, 2020 Expires: December 26, 2020 IPFIX export of Segment Routing IPv6 information draft-patki-srv6-ipfix-00 Abstract This document introduces new IP Flow Information Exchange (IPFIX) information elemements for exporting IPv6 Segment Routing Header (SRH). 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 26, 2020. 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 carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Patki Expires December 26, 2020 [Page 1] Internet-Draft IPFIX export of SRv6 information June 2020 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1.1. Requirements Language . . . . . . . . . . . . . . . . . . 2 2. New IPFIX Information Elements . . . . . . . . . . . . . . . 3 3. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 3 4. Security Considerations . . . . . . . . . . . . . . . . . . . 4 5. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 4 6. References . . . . . . . . . . . . . . . . . . . . . . . . . 4 6.1. Normative References . . . . . . . . . . . . . . . . . . 4 6.2. Informative References . . . . . . . . . . . . . . . . . 4 Appendix A. Encoding Example . . . . . . . . . . . . . . . . . . 5 A.1. Template Record . . . . . . . . . . . . . . . . . . . . . 5 A.2. Data Set . . . . . . . . . . . . . . . . . . . . . . . . 6 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 8 1. Introduction IP Flow Information Export (IPFIX) [RFC7011] provides network administrators with traffic flow information using the Information Elements (IEs) defined in the "IPFIX Information Elements" registry [IANA-IPFIX]. Based on the traffic flow information, network administrators know the amount and direction of the traffic in their network and can then optimize the network when needed. For example, the collected information could be used for traffic monitoring and, optionally, for traffic optimization according to the operator's policy. A new type of Routing Extension Header called Segment Routing Header (SRH) is defined by [RFC8754] which is used for applying Segment Routing on IPv6 data plane. This document defined new IPFIX IEs to export the contents of SRH. Currently this document is limited to exporting based SRH excluding the TLV, however, further versions of this document intend to include TLVs and variations in the SRH that may be defined in the near future. 1.1. Requirements Language The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119]. Patki Expires December 26, 2020 [Page 2] Internet-Draft IPFIX export of SRv6 information June 2020 2. New IPFIX Information Elements This section defines new IPFIX IEs corresponding to various fields in the SRH. ipv6SRHLastEntry The index (zero based) in the Segment List in the SRH, of the last element of the Segment List. ipv6SRHFlags 8-bit flags defined in the SRH. ipv6SRHTag Tag is an identifier that marks a packet as part of a class or group of packets, e.g., packets sharing the same set of properties. This information element contains the value of the Tag field. ipv6SRHSegment 128-bit IPv6 address that represents an SRv6 segment. ipv6SRHSegmentList A basicList [RFC6313][RFC7012] of ipv6SRHSegment that contains the Segment List in the SRH header. Like in the SRH header, the basicList is encoded starting from the last segment of the SR Policy. That is, the first element of the basicList contains the last segment of the SR Policy, the second element contains the penultimate segment of the SR Policy, and so on. This information element has variable length. 3. IANA Considerations This document specifies IPFIX IEs to enable export of Segment Routing IPv6 information. IANA needs to assign the following Element IDs for these IEs in the "IPFIX Information Elements" registry [IANA-IPFIX]: -------------------------------------------------------------------- | Element | Name | Abstract | Data Type | Refer- | | ID | | Data Type | Semantics | ence | -------------------------------------------------------------------- | TBD1 | ipv6SRHLastEntry | unsigned8 | identifier | RFC8754 | | TBD2 | ipv6SRHFlags | unsigned8 | flags | RFC8754 | | TBD3 | ipv6SRHTag | unsigned16 | identifier | RFC8754 | | TBD4 | ipv6SRHSegment | ipv6address| default | RFC8754 | | TBD5 | ipv6SRHSegmentList | basicList | list | RFC8754 | -------------------------------------------------------------------- Patki Expires December 26, 2020 [Page 3] Internet-Draft IPFIX export of SRv6 information June 2020 4. Security Considerations The security considerations in [RFC7011] apply. 5. Acknowledgements TBD 6. References 6.1. Normative References [IANA-IPFIX] IANA, "IP Flow Information Export (IPFIX) Entities", . [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . [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, . [RFC7011] Claise, B., Ed., Trammell, B., Ed., and P. Aitken, "Specification of the IP Flow Information Export (IPFIX) Protocol for the Exchange of Flow Information", STD 77, RFC 7011, DOI 10.17487/RFC7011, September 2013, . [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, . 6.2. Informative References [RFC7012] Claise, B., Ed. and B. Trammell, Ed., "Information Model for IP Flow Information Export (IPFIX)", RFC 7012, DOI 10.17487/RFC7012, September 2013, . Patki Expires December 26, 2020 [Page 4] Internet-Draft IPFIX export of SRv6 information June 2020 Appendix A. Encoding Example In this section, an example is provided to show IPFIX encoding format for the newly introduced IEs. Template definition and data set corresponding to 3 observed SRH headers are illustrated. Observed SRH headers: SRH 1: Segments Left = 2, Last Entry = 2, Flags = 0, Tag = 0, Segment List = 1111::1, 2222::2, 3333::3 SRH 2: Segments Left = 1, Last Entry = 1, Flags = 0, Tag = 100, Segment List = 4444::4, 5555::5 SRH 3: Segments Left = 1, Last Entry = 2, Flags = 0, Tag = 200, Segment List = 6666::6, 7777::7, 8888::8 A.1. Template Record Sample template consisting of the new IEs: 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 = 24 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Template ID = 256 | Field Count = 4 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0| ipv6SRHLastEntry = TBD1 | Field Length = 1 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0| ipv6SRHFlags = TBD2 | Field Length = 1 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0| ipv6SRHTag = TBD3 | Field Length = 2 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0| ipv6SRHSegmentList = TBD5 | Field Length = 0xFFFF | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 1: Sample Template Patki Expires December 26, 2020 [Page 5] Internet-Draft IPFIX export of SRv6 information June 2020 A.2. Data Set Data set for the observed SRH headers using the template defined above: Patki Expires December 26, 2020 [Page 6] Internet-Draft IPFIX export of SRv6 information June 2020 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 = 168 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ipv6SRHLast | ipv6SRHFlags | ipv6SRHTag = 0 | | Entry = 2 | = 0 | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | 255 | List Length = 53 |semantic=allof | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ipv6SRHSegment = TBD4 | Field Length = 16 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Segment List[0] = 1111::1 (16 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Segment List[1] = 2222::2 (16 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Segment List[2] = 3333::3 (16 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ipv6SRHLast | ipv6SRHFlags | ipv6SRHTag = 100 | | Entry = 1 | = 0 | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | 255 | List Length = 37 |semantic=allof | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ipv6SRHSegment = TBD4 | Field Length = 16 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Segment List[0] = 4444::4 (16 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Segment List[1] = 5555::5 (16 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ipv6SRHLast | ipv6SRHFlags | ipv6SRHTag = 200 | | Entry = 2 | = 0 | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | 255 | List Length = 53 |semantic=allof | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ipv6SRHSegment = TBD4 | Field Length = 16 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Segment List[0] = 6666::6 (16 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Segment List[1] = 7777::7 (16 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Segment List[2] = 8888::8 (16 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 2: Data Set Patki Expires December 26, 2020 [Page 7] Internet-Draft IPFIX export of SRv6 information June 2020 Author's Address Dhananjay Patki Cisco Systems, Inc. Cessna Business Park SEZ, Kadubeesanahalli Bangalore, Karnataka 560087 India Email: dhpatki@cisco.com Patki Expires December 26, 2020 [Page 8]