Network Working Group T. Graf Internet-Draft Swisscom Intended status: Standards Track B. Claise Expires: 11 March 2023 Huawei P. Francois INSA-Lyon 7 September 2022 Export of Segment Routing IPv6 Information in IP Flow Information Export (IPFIX) draft-ietf-opsawg-ipfix-srv6-srh-00 Abstract This document introduces new IP Flow Information Export (IPFIX) information elements to identify the SRv6 Segment Routing Header dimensions, the SRv6 Control Plane Protocol and the SRv6 Endpoint Behavior that traffic is being forwarded with. 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 11 March 2023. Copyright Notice Copyright (c) 2022 IETF Trust and the persons identified as the document authors. All rights reserved. Graf, et al. Expires 11 March 2023 [Page 1] Internet-Draft IPFIX Segment Routing IPv6 Information September 2022 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. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. IPFIX Information Elements . . . . . . . . . . . . . . . . . 3 3. Use Cases . . . . . . . . . . . . . . . . . . . . . . . . . . 4 4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 4 4.1. srhFlagsIPv6 . . . . . . . . . . . . . . . . . . . . . . 6 4.2. srhTagIPv6 . . . . . . . . . . . . . . . . . . . . . . . 6 4.3. srhSegmentIPv6 . . . . . . . . . . . . . . . . . . . . . 6 4.4. srhActiveSegmentIPv6 . . . . . . . . . . . . . . . . . . 6 4.5. srhSegmentIPv6BasicList . . . . . . . . . . . . . . . . . 7 4.6. srhSegmentIPv6ListSection . . . . . . . . . . . . . . . . 7 4.7. srhSegmentIPv6sLeft . . . . . . . . . . . . . . . . . . . 7 4.8. srhSectionIPv6 . . . . . . . . . . . . . . . . . . . . . 7 4.9. srhActiveSegmentIPv6Type . . . . . . . . . . . . . . . . 7 4.10. srhSegmentLocatorLength . . . . . . . . . . . . . . . . . 8 4.11. srhSegmentEndpointBehavior . . . . . . . . . . . . . . . 8 5. Operational Considerations . . . . . . . . . . . . . . . . . 9 5.1. SRv6 Segment List . . . . . . . . . . . . . . . . . . . . 9 5.2. Compressed SRv6 Segment List Decomposition . . . . . . . 10 6. Security Considerations . . . . . . . . . . . . . . . . . . . 10 7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 10 8. References . . . . . . . . . . . . . . . . . . . . . . . . . 10 8.1. Normative References . . . . . . . . . . . . . . . . . . 10 8.2. Informative References . . . . . . . . . . . . . . . . . 10 Appendix A. IPFIX Encoding Examples . . . . . . . . . . . . . . 12 A.1. Template Record and Data Set with Segment Basic List . . 12 A.2. Template Record and Data Set with Segment List Section . 15 A.3. Template Record and Data Set with SRH Section . . . . . . 17 A.4. Options Template Record and Data Set for SRv6 end point behavior and Locator Length . . . . . . . . . . . . . . . 20 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 21 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. Graf, et al. Expires 11 March 2023 [Page 2] Internet-Draft IPFIX Segment Routing IPv6 Information September 2022 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 propagate Segment Identifiers (SIDs) for the IPv6 data plane. SRv6 segment endpoint behaviors have been defined in [RFC8986] and describe how packets should be processed. This document defines eleven new IPFIX Information Elements (IEs) and three new subregistries within the "IPFIX Information Elements" registry [RFC7012], respectively for the new SRH dimensions, SRv6 endpoint behaviors and routing protocol and PCEP extensions. 2. IPFIX Information Elements This section defines and describes the new IPFIX IEs. srhFlagsIPv6 8-bit flags defined in the SRH. srhTagIPv6 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. srhSegmentIPv6 128-bit IPv6 address that represents an SRv6 segment. srhActiveSegmentIPv6 128-bit IPv6 address that represents the active SRv6 segment. srhSegmentIPv6BasicList Ordered basicList [RFC6313] 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. That is, the first element of the Segment List (Segment List[0]) contains the last segment of the SR Policy, the second element contains the penultimate segment of the SR Policy, and so on. srhSegmentIPv6ListSection Exposes the SRH Segment List as defined in section 2 of [RFC8754] as series of n octets. srhSegmentIPv6sLeft 8-bit unsigned integer defining the number of route segments remaining to reach the end of the segment list. Graf, et al. Expires 11 March 2023 [Page 3] Internet-Draft IPFIX Segment Routing IPv6 Information September 2022 srhSectionIPv6 Exposes the SRH and its TLV's as defined in section 2 of [RFC8754] as series of n octets. srhActiveSegmentIPv6Type Name of the routing protocol or PCEP extension from where the active SRv6 segment has been learned from. srhSegmentLocatorLength The number of significant bits. Together with srhSegmentIPv6 it enables the calculation of the SRv6 Locator. srhSegmentEndpointBehavior 16-bit unsigned integer that represents a SRv6 Endpoint behavior. Note that the srhSegmentIPv6, srhSegmentLocatorLength, and srhSegmentEndpointBehavior IPFIX IEs are generic fields, to be used in the context of IPFIX Options Templates or IPFIX Structured Data [RFC6313]. 3. Use Cases By using srhSegmentIPv6BasicList(TBD5) or the srhSegmentIPv6ListSection (TBD6), srhActiveSegmentIPv6 (TBD4), srhSegmentIPv6sLeft (TBD7), srhActiveSegmentIPv6Type(TBD9), the forwardingStatus(89), and some counters information, it is possible to answer the following questions (amongst others): * how many packets are forwarded or dropped * if dropped, for which reasons, * identify the active segment and its control plane protocol, * the SRv6 segment list, * the next SRv6 node and its type, * and how many SRv6 segments are left. 4. IANA Considerations This document requests IANA to create new IEs (see table 1) and three new subregistries called "IPFIX IPv6 SRH Flags" (table 2), "IPFIX IPv6 SRH Segment type" (table 3) and "IPFIX SRV6 Endpoint Behavior" (table 4) under the "IPFIX Information Elements" registry [RFC7012] available at [IANA-IPFIX] and assign the following initial code points. Graf, et al. Expires 11 March 2023 [Page 4] Internet-Draft IPFIX Segment Routing IPv6 Information September 2022 +-------+----------------------------+ |Element| Name | | ID | | +-------+----------------------------+ | TBD1 | srhFlagsIPv6 | | | | +-------+----------------------------+ | TBD2 | srhTagIPv6 | | | | +-------+----------------------------+ | TBD3 | srhSegmentIPv6 | | | | +-------+----------------------------+ | TBD4 | srhActiveSegmentIPv6 | | | | +-------+----------------------------+ | TBD5 | srhSegmentIPv6BasicList | | | | +-------+----------------------------+ | TBD6 | srhSegmentIPv6ListSection | | | | +-------+----------------------------+ | TBD7 | srhSegmentIPv6sLeft | | | | +-------+----------------------------+ | TBD8 | srhSectionIPv6 | | | | +-------+----------------------------+ | TBD9 | srhActiveSegmentIPv6Type | | | | +-------+----------------------------+ | TBD10 | srhSegmentLocatorLength | | | | +-------+----------------------------+ | TBD11 | srhSegmentEndpointBehavior | | | | +-------+----------------------------+ Table 1: Creates IEs in the "IPFIX Information Elements" registry Note to the RFC-Editor: * Please replace TBD1 - TBD16 with the values allocated by IANA * Please replace the [RFC-to-be] with the RFC number assigned to this document Graf, et al. Expires 11 March 2023 [Page 5] Internet-Draft IPFIX Segment Routing IPv6 Information September 2022 4.1. srhFlagsIPv6 Name: srhFlagsIPv6 ElementID: TBD1 Description: This Information Element identifies the 8-bit flags defined in the SRH. Values for this Information Element are listed in the "IPFIX IPv6 SRH Flags" registry, see Abstract Data Type: unsigned8 Data Type Semantics: flags Reference: [RFC-to-be], RFC8754[IANA-IPFIX]. srhFlagsIPv6 values must not be directly added to this "IPFIX IPv6 SRH Flags" registry. They must instead be added to the "Segment Routing Header Flags" registry. Both the "IPFIX IPv6 SRH Flags" and the "Segment Routing Header Flags" registries must be kept in synch. Initial values in the registry are defined by the table below. +--------+-------------------+--------------------------------------+ | Value | Description | Reference | +--------+-------------------+--------------------------------------+ | 0-1 | Unassigned | | +--------+-------------------+--------------------------------------+ | 2 | O-flag | [RFC-ietf-6man-spring-srv6-oam-13] | +--------+-------------------+--------------------------------------+ | 3-7 | Unassigned | | +--------+-------------------+--------------------------------------+ Table 2: "IPFIX IPv6 SRH Flags" registry 4.2. srhTagIPv6 Name: srhTagIPv6 ElementID: TBD2 Description: This Information Element identifies the 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. Abstract Data Type: unsigned16 Data Type Semantics: identifier Reference: [RFC-to-be], RFC8754 4.3. srhSegmentIPv6 Name: srhSegmentIPv6 ElementID: TBD3 Description: This Information Element identifies the 128-bit IPv6 address that represents an SRv6 segment. Abstract Data Type: ipv6address Data Type Semantics: default Reference: [RFC-to-be], RFC8754 4.4. srhActiveSegmentIPv6 Name: srhActiveSegmentIPv6 ElementID: TBD4 Description: This Information Element identifies the 128-bit IPv6 address that represents the active SRv6 segment. Abstract Data Type: ipv6address Data Type Semantics: default Reference: [RFC-to-be], RFC8754 Graf, et al. Expires 11 March 2023 [Page 6] Internet-Draft IPFIX Segment Routing IPv6 Information September 2022 4.5. srhSegmentIPv6BasicList Name: srhSegmentIPv6BasicList ElementID: TBD5 Description: This Information Element identifies the Ordered basicList [RFC6313] 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. That is, the first element of the Segment List (Segment List[0]) contains the last segment of the SR Policy, the second element contains the penultimate segment of the SR Policy, and so on. Abstract Data Type: basicList Data Type Semantics: list Reference: [RFC-to-be], RFC8754 4.6. srhSegmentIPv6ListSection Name: srhSegmentIPv6ListSection ElementID: TBD6 Description: Exposes the SRH Segment List as defined in section 2 of Abstract Data Type: octetArray Data Type Semantics: default Reference: [RFC-to-be], RFC8754[RFC8754] as series of n octets. 4.7. srhSegmentIPv6sLeft Name: srhSegmentIPv6sLeft ElementID: TBD7 Description: This Information Element identifies the 8-bit unsigned integer defining the number of route segments remaining to reach the end of the segment list. Abstract Data Type: unsigned8 Data Type Semantics: quantity Reference: [RFC-to-be], RFC8754 4.8. srhSectionIPv6 Name: srhSectionIPv6 ElementID: TBD8 Description: This Information Element exposes the SRH and its TLV's as defined in section 2 of Abstract Data Type: octetArray Data Type Semantics: default Reference: [RFC-to-be], RFC8754[RFC8754] as series of n octets. 4.9. srhActiveSegmentIPv6Type Name: srhActiveSegmentIPv6Type ElementID: TBD9 Description: This Information Element identifies the name of the routing protocol or PCEP extension from where the active SRv6 segment has been learned from. Values for this Information Element are listed in the "IPFIX IPv6 SRH Segment type" registry, see Abstract Data Type: unsigned8 Data Type Semantics: identifier Reference: [RFC-to-be][IANA-IPFIX]. Initial values in the registry are defined by the table below. New assignments of values will be administered by IANA and are subject to Expert Review [RFC8126]. Experts need to check definitions of new values for completeness, accuracy, and redundancy. Graf, et al. Expires 11 March 2023 [Page 7] Internet-Draft IPFIX Segment Routing IPv6 Information September 2022 +-------+--------------------+--------------------------------------+ | Value | Description | Reference | +-------+--------------------+--------------------------------------+ | TBD12 | Unknown | [RFC-to-be] | | | | | +-------+--------------------+--------------------------------------+ | TBD13 | Path Computation | [RFC-to-be], | | | Element | draft-ietf-pce-segment-routing-ipv6 | +-------+--------------------+--------------------------------------+ | TBD14 | OSPFv3 | [RFC-to-be], | | | Segment Routing | draft-li-ospf-ospfv3-srv6-extensions | +-------+--------------------+--------------------------------------+ | TBD15 | IS-IS | [RFC-to-be] | | | Segment Routing | draft-ietf-lsr-isis-srv6-extensions | +-------+--------------------+--------------------------------------+ | TBD16 | BGP Segment | [RFC-to-be], | | | Routing Prefix-SID | draft-ietf-bess-srv6-services | +-------+--------------------+--------------------------------------+ Table 3: "IPFIX IPv6 SRH Segment type" subregistry 4.10. srhSegmentLocatorLength Name: srhSegmentLocatorLength ElementID: TBD10 Description: This Information Element identifies the number of significant bits and together with srhSegmentIPv6 enables the calculation of the SRv6 Locator. Abstract Data Type: unsigned8 Data Type Semantics: default Reference: [RFC-to-be], RFC8986 Section 3.1 4.11. srhSegmentEndpointBehavior Name: srhSegmentEndpointBehavior ElementID: TBD11 Description: This Information Element identifies the 16-bit SRv6 Endpoint behavior. Values for this Information Element are listed in the "IPFIX SRV6 Endpoint Behavior" registry, see Abstract Data Type: unsigned16 Data Type Semantics: identifier Reference: [RFC-to-be], RFC8986 Section 4[IANA-IPFIX]. srhSegmentEndpointBehavior values must not be directly added to this "IPFIX SRV6 Endpoint Behavior" registry. They must instead be added to the "Segment Routing SRv6 Endpoint Behaviors" registry. Both the "IPFIX SRV6 Endpoint Behavior" and the "Segment Routing SRv6 Endpoint Behaviors" registries must be kept in synch. Graf, et al. Expires 11 March 2023 [Page 8] Internet-Draft IPFIX Segment Routing IPv6 Information September 2022 +--------+-------+-------------------------------+------------------+ | Value | Hex | Endpoint Behavior | Reference | Change Controller| +--------+-------+-------------------------------+------------------+ | | | | | | +--------+-------+-------------------------------+------------------+ | | | | | | +--------+-------+-------------------------------+------------------+ | | | | | | +--------+-------+-------------------------------+------------------+ Table 4: "IPFIX SRV6 Endpoint Behavior" registry 5. Operational Considerations 5.1. SRv6 Segment List The zero or more 128-bit IPv6 addresses in the SRH [RFC8754] can be exported in two different ways, with two different IPFIX IEs: * srhSegmentIPv6BasicList * srhSegmentIPv6ListSection The srhSegmentIPv6BasicList encodes the SID list of IPv6 addresses with a basicList, specified in the IPFIX Structured Data [RFC6313]. This encoding offers the advantage to the data collection that the different IPv6 addresses are already structured as a list, without the need of post processing. However, this method requires some extra processing on the exporter, to realize the BasicList data mapping. The srhSegmentIPv6ListSection, on the other hand, encodes the list of IPv6 addresses as an octetArray. This doesn't impose any data flow manipulation on the exporter, facilitating the immediate export. However, the data collection must be able to decode the IPv6 addresses according the SR specifications. Compared to the srhSegmentIPv6BasicList, the srhSegmentIPv6ListSection flow records length is slightly reduced. It is not expected that an exporter would support both srhSegmentIPv6BasicList and srhSegmentIPv6ListSection at the same time. Graf, et al. Expires 11 March 2023 [Page 9] Internet-Draft IPFIX Segment Routing IPv6 Information September 2022 5.2. Compressed SRv6 Segment List Decomposition The SRv6 segment list in the IPFIX IEs srhSegmentIPv6BasicList and srhSegmentIPv6ListSection could contain compressed-SID containers as described in [I-D.ietf-spring-srv6-srh-compression]. The SID endpoint behaviors described in section 4 of [I-D.ietf-spring-srv6-srh-compression] determine wherever the segment list is compressed or not. The SID Locator as described in section 3.1 [RFC8986], determines the common most significant bits. 6. Security Considerations There exists no significant extra security considerations regarding the allocation of these new IPFIX IEs compared to [RFC7012]. 7. Acknowledgements The authors would like to thank Yao Liu, Paolo Lucente, Eduard Vasilenko, Alex Huang Feng and Bruno Decraene for their review and valuable comments. 8. References 8.1. 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, . [RFC7012] Claise, B., Ed. and B. Trammell, Ed., "Information Model for IP Flow Information Export (IPFIX)", RFC 7012, DOI 10.17487/RFC7012, September 2013, . [RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for Writing an IANA Considerations Section in RFCs", BCP 26, RFC 8126, DOI 10.17487/RFC8126, June 2017, . 8.2. Informative References Graf, et al. Expires 11 March 2023 [Page 10] Internet-Draft IPFIX Segment Routing IPv6 Information September 2022 [I-D.ietf-bess-srv6-services] Dawra, G., 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-15, 22 March 2022, . [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(Editor), C., Negi, M. S., Sivabalan, S., Koldychev, M., Kaladharan, P., and Y. Zhu, "Path Computation Element Communication Protocol (PCEP) Extensions for Segment Routing leveraging the IPv6 dataplane", Work in Progress, Internet-Draft, draft-ietf-pce-segment-routing-ipv6-14, 10 July 2022, . [I-D.ietf-spring-srv6-srh-compression] Cheng, W., Filsfils, C., Li, Z., Decraene, B., Cai, D., Voyer, D., Clad, F., Zadok, S., Guichard, J. N., Aihua, L., Raszuk, R., and C. Li, "Compressed SRv6 Segment List Encoding in SRH", Work in Progress, Internet-Draft, draft- ietf-spring-srv6-srh-compression-02, 11 July 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"", . Graf, et al. Expires 11 March 2023 [Page 11] Internet-Draft IPFIX Segment Routing IPv6 Information September 2022 [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, . [RFC8986] Filsfils, C., Ed., Camarillo, P., Ed., Leddy, J., Voyer, D., Matsushima, S., and Z. Li, "Segment Routing over IPv6 (SRv6) Network Programming", RFC 8986, DOI 10.17487/RFC8986, February 2021, . Appendix A. IPFIX Encoding Examples This appendix represents three different encodings for the newly introduced IEs, for the example values in the table 5. The three different encodings uses the following IEs, respectively: srhSegmentIPv6BasicList, srhSegmentIPv6ListSection, and srhSectionIPv6. +-----+------+-----+------------------+--------------------------| | SRH | SRH | SRH | Active Segment | Segment List | | Nr | Flags| Tag | Type | | +-----+------+-----+------------------+--------------------------+ | 1 | 0 | 123 | IS-IS [TBD15] | 2001:db8::1, 2001:db8::2,| | | | | | 2001:db8::3 | +-----+------+-----+------------------+--------------------------+ | 2 | 0 | 456 | IS-IS [TBD15] | 2001:db8::4, 2001:db8::5 | +-----+------+-----+------------------+--------------------------+ | 3 | 0 | 789 | IS-IS [TBD15] | 2001:db8::6 | +-----+------+-----+------------------+--------------------------+ Table 5: three observed SRH headers and their routing protocol A.1. Template Record and Data Set with Segment Basic List With this encoding, the examples in Table 5 are represented with the following IEs: * SR Flags => srhFlagsIPv6 * SR Tag => srhTagIPv6 * Active Segment Type => srhActiveSegmentIPv6Type * Segment List => srhSegmentIPv6BasicList Graf, et al. Expires 11 March 2023 [Page 12] Internet-Draft IPFIX Segment Routing IPv6 Information September 2022 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| srhFlagsIPv6 = TBD1 | Field Length = 1 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0| srhTagIPv6 = TBD2 | Field Length = 2 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0|srhActiveSegmentIPv... = TBD9| Field Length = 1 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0|srhSegmentIPv6BasicList= TBD5| Field Length = 0xFFFF | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Table 6: Template Record with Basic List Encoding Format In this example, the Template ID is 256, which will be used in the Data Record. The field length for srhSegmentIPv6BasicList 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]. 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 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | srhFlagsIPv6 | srhTagIPv6 = 123 | srhActiveSegme| | = 0 | | ntIPv...=TBD15| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | 255 | List Length = 53 |semantic= | | | |ordered | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | srhSegmentIPv6 = TBD3 | Field Length = 16 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Segment List[0] = 2001:db8::1 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Graf, et al. Expires 11 March 2023 [Page 13] Internet-Draft IPFIX Segment Routing IPv6 Information September 2022 | Segment List[1] = 2001:db8::2 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Segment List[2] = 2001:db8::3 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | srhFlagsIPv6 | srhTagIPv6 = 456 | srhActiveSegme| | = 0 | | ntIPv...=TBD15| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | 255 | List Length = 37 |semantic= | | | |ordered | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | srhSegmentIPv6 = TBD3 | Field Length = 16 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Segment List[0] = 2001:db8::4 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Segment List[1] = 2001:db8::5 (16 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | srhFlagsIPv6 | srhTagIPv6 = 789 | srhActiveSegme| | = 0 | | ntIPv...=TBD15| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | 255 | List Length = 21 |semantic= | | | |ordered | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | srhSegmentIPv6 = TBD3 | Field Length = 16 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Graf, et al. Expires 11 March 2023 [Page 14] Internet-Draft IPFIX Segment Routing IPv6 Information September 2022 | Segment List[0] = 2001:db8::6 ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Table 7: Data Set Encoding Format for Basic List A.2. Template Record and Data Set with Segment List Section With this encoding, the examples in Table 5 are represented with the following IEs: * SR Flags => srhFlagsIPv6 * SR Tag => srhTagIPv6 * Active Segment Type => srhActiveSegmentIPv6Type * Segment List => srhSegmentIPv6List 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 = 257 | Field Count = 4 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0| srhFlagsIPv6 = TBD1 | Field Length = 1 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0| srhTagIPv6 = TBD2 | Field Length = 2 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0|srhActiveSegmentIPv... = TBD9| Field Length = 1 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0| srhSegmentIPv6List | Field Length = 0xFFFF | | | Section=TBD6 | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Table 8: Template Record with Segment List Section Encoding Format In this example, the Template ID is 257, which will be used in the Data Record. The field length for srhSegmentIPv6ListSection is 0xFFFF, which means the length of this IE is variable. Graf, et al. Expires 11 March 2023 [Page 15] Internet-Draft IPFIX Segment Routing IPv6 Information September 2022 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 = 257 | Length = 116 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | srhFlagsIPv6 | srhTagIPv6 = 123 | srhActiveSegme| | = 0 | | ntIPv...=TBD15| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | 0xFFFF | 2001:db8::1 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | 2001:db8::2 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | 2001:db8::3 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | srhFlagsIPv6 | srhTagIPv6 = 456 | | | = 0 | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | srhActiveSegme| 0xFFFF | 2001:db8::4 | | ntIPv...=TBD15| | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | 2001:db8::5 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Graf, et al. Expires 11 March 2023 [Page 16] Internet-Draft IPFIX Segment Routing IPv6 Information September 2022 | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... |srhFlagsIPv6=0 | srhTagIPv6... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | = 789 | srhActiveSegment | 0xFFFF | | | IPv6Type=TBD15 | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | 2001:db8::6 ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Table 9: Data Set Encoding Format for Segment List Section A.3. Template Record and Data Set with SRH Section With this encoding, the examples in Table 5 are represented with the following IEs: * SR Flags + SR Tag + Segment List => srhSectionIPv6 * Active Segment Type => srhActiveSegmentIPv6Type 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 = 16 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Template ID = 258 | Field Count = 2 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0| srhActiveSegmentIP... = TBD9| Field Length = 1 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0| srhSectionIPv6 = TBD8 | Field Length = 0xFFFF | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Table 10: Template Record with SRH Section Encoding Format Graf, et al. Expires 11 March 2023 [Page 17] Internet-Draft IPFIX Segment Routing IPv6 Information September 2022 In this example, the Template ID is 258, which will be used in the Data Record. The field length for srhSectionIPv6 is 0xFFFF, which means the length of this IE is variable. 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 = 258 | Length = (*) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | srhActiveSegmentIPv6Type = TBD15 | 0xFFFF | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Next Header | Hdr Ext Len | Routing Type | Segments Left | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Last Entry | Flags | Tag | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Segment List[0] 2001:db8::1 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Segment List[1] 2001:db8::2 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Segment List[2] 2001:db8::3 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ Optional Type Length Value objects (variable) ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | srhActiveSegmentIPv6Type = TBD15 | 0xFFFF | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Next Header | Hdr Ext Len | Routing Type | Segments Left | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Last Entry | Flags | Tag | Graf, et al. Expires 11 March 2023 [Page 18] Internet-Draft IPFIX Segment Routing IPv6 Information September 2022 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Segment List[0] 2001:db8::4 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Segment List[1] 2001:db8::5 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ Optional Type Length Value objects (variable) ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | srhActiveSegmentIPv6Type = TBD15 | 0xFFFF | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Next Header | Hdr Ext Len | Routing Type | Segments Left | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Last Entry | Flags | Tag | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Segment List[0] 2001:db8::6 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ Optional Type Length Value objects (variable) ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Table 11: Data Set Encoding Format for SRH Section (*) The Length must be calculated to include the optional Type Length Value objects. Graf, et al. Expires 11 March 2023 [Page 19] Internet-Draft IPFIX Segment Routing IPv6 Information September 2022 A.4. Options Template Record and Data Set for SRv6 end point behavior and Locator Length This appendix provides an SRv6 EndPoint Bevahior Options Template example, for the values presented in Table 12. In the Options Template case, the srhEndPointIPv6 Information Element is a Scope field +-------+-------------+-------------------------+----------------+ | Entry | SRH End | SRH End | SRH Segment | | Nr | Point IPv6 | Point Behavior | Locator Length | +-------+-------------+-------------------------+----------------+ | 1 | 2001:db8::1 | End [1] | 48 | +-------+-------------+-------------------------+----------------+ | 2 | 2001:db8::4 | End with NEXT-CSID [43] | 48 | +-------+-------------+-------------------------+----------------+ | 3 | 2001:db8::6 | End.DX6 [16] | 48 | +-------+-------------+-------------------------+----------------+ Table 12: three observed SRv6 End Point Behaviors 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 = 3 | Length = 24 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Template ID 259 | Field Count = 3 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Scope Field Count = 1 |0| srhSegmentIPv6 = TBD3 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Scope 1 Field Length = 4 |0|srhSegmentEndpointBeh..=TBD11| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Field Length = 1 |0|srhSegmentLocatorLength=TBD10| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Field Length = 4 | Padding | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Table 13: Template Record with SRH Section Encoding Format In this example, the Template ID is 259, which will be used in the Data Record. The data set is represented as follows: Graf, et al. Expires 11 March 2023 [Page 20] Internet-Draft IPFIX Segment Routing IPv6 Information September 2022 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 = 259 | Length = 28 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | 2001:db8::1 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | End [1] | 48 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | 2001:db8::4 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | End with NEXT-CSID [43] | 48 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | 2001:db8::6 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | End.DX6 [16] | 48 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Table 14: Data Set Encoding Format for SRH Section (*) The Length must be calculated to include the optional Type Length Value objects. Authors' Addresses Thomas Graf Swisscom Binzring 17 CH-8045 Zurich Switzerland Email: thomas.graf@swisscom.com Benoit Claise Huawei Email: benoit.claise@huawei.com Pierre Francois INSA-Lyon Lyon France Email: pierre.francois@insa-lyon.fr Graf, et al. Expires 11 March 2023 [Page 21]