Network Working Group C. Lin Internet Draft New H3C Technologies Intended status: Standards Track Y. Liu Expires: March 09, 2025 China Mobile Y. Zhu China Telecom September 09, 2024 BGP-LS Advertisement of TE Policy Performance Metric draft-lin-idr-bgpls-te-policy-pm-04 Abstract This document describes a way to advertise the performance metrics for Traffic Engineering (TE) Policy using BGP Link State (BGP-LS). 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), its areas, and its working groups. Note that other groups may also distribute working documents as Internet- Drafts. 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." 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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. Table of Contents 1. Introduction...................................................3 1.1. Requirements Language.....................................3 2. Advertisement of TE Policy Performance Metric..................3 3. Extensions for Round-trip TE Performance Metric................4 3.1. Round-trip Delay TLV......................................4 3.2. Min/Max Round-trip Delay TLV..............................4 3.3. Round-trip Delay Variation TLV............................5 3.4. Round-trip Loss TLV.......................................6 4. Security Considerations........................................6 5. Management Considerations......................................7 6. IANA Considerations............................................7 7. References.....................................................7 7.1. Normative References......................................7 Authors' Addresses................................................9 Lin, et al. Expires March 09, 2025 [Page 2] Internet-Draft BGP-LS TE Policy Performance Metric September 2024 1. Introduction BGP Link State (BGP-LS) can be used to distribute link-state and traffic engineering (TE) information to external components [RFC9552]. [I-D.ietf-idr-bgp-ls-te-path] describes the mechanism for BGP-LS to distribute the information of TE policies. [I-D.ietf-idr- bgp-ls-sr-policy] describes the mechanism for BGP-LS to distribute the information of SR policies. In some network scenarios, the controller needs to obtain the performance information of TE Policies, which can be used in service placement to meet better customer requirements and utilize network resources more efficiently. This document describes a way to advertise the performance metrics for Traffic Engineering (TE) Policy using BGP Link State (BGP-LS). 1.1. Requirements Language The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "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. Advertisement of TE Policy Performance Metric [RFC8571] defines several Link Attribute TLVs for BGP-LS to carry the IGP Traffic Engineering Performance Metric Extensions: TLV Code Point Value -------------------------------------------------------- 1114 Unidirectional Link Delay 1115 Min/Max Unidirectional Link Delay 1116 Unidirectional Delay Variation 1117 Unidirectional Link Loss The above TLVs can be re-used to advertise the performance metrics for TE Policies. When used to describe the performance metric of the TE Policy NLRI, they are carried in the optional non-transitive BGP Path Attribute "BGP-LS Attribute" defined in [RFC9552]. The semantics of the above TLVs comply with [RFC8571], except for that they are extended to describe TE Policies besides IGP links. Lin, et al. Expires March 09, 2025 [Page 3] Internet-Draft BGP-LS TE Policy Performance Metric September 2024 The performance metric of TE Policy may be measured at the headend, for example, by using TWAMP for SR Policy. But the measurement methods are out of the scope of this document. The existing performance metrics above are all unidirectional. However, there are also requirements to advertise round-trip performance metrics for TE Policies. The BGP-LS extensions for round-trip TE performance metrics are defined in the following section. 3. Extensions for Round-trip TE Performance Metric 3.1. Round-trip Delay TLV This TLV advertises the average round-trip delay for TE Policy. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |A| RESERVED | Delay | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ where: o Type: TBD o Length: 4 o Reserved: Reserved for future use. MUST be set to 0 when sent and MUST be ignored when received. o A: Anomalous (A) Bit. Same with the A Bit in Unidirectional Link Delay TLV [RFC8571]. o Delay: Similar with the Delay filed in Unidirectional Link Delay TLV [RFC8571], except for that the delay is round-trip. 3.2. Min/Max Round-trip Delay TLV This TLV advertises the minimum and maximum round-trip delay for TE Policy. Lin, et al. Expires March 09, 2025 [Page 4] Internet-Draft BGP-LS TE Policy Performance Metric September 2024 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |A| RESERVED | Min Delay | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | RESERVED | Max Delay | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ where: o Type: TBD o Length: 4 o Reserved: Reserved for future use. MUST be set to 0 when sent and MUST be ignored when received. o A: Anomalous (A) Bit. Same with the A Bit in Min/Max Unidirectional Link Delay TLV [RFC8571]. o Min Delay: Similar with the Min Delay filed in Min/Max Unidirectional Link Delay TLV [RFC8571], except for that the delay is round-trip. o Max Delay: Similar with the Max Delay filed in Min/Max Unidirectional Link Delay TLV [RFC8571], except for that the delay is round-trip. 3.3. Round-trip Delay Variation TLV This TLV advertises the average round-trip delay variation for TE Policy. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |A| RESERVED | Delay Variation | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ where: o Type: TBD o Length: 4 Lin, et al. Expires March 09, 2025 [Page 5] Internet-Draft BGP-LS TE Policy Performance Metric September 2024 o Reserved: Reserved for future use. MUST be set to 0 when sent and MUST be ignored when received. o A: Anomalous (A) Bit. Same with the A Bit in Unidirectional Delay Variation TLV [RFC8571]. o Delay Variation: Similar with the Delay Variation filed in Unidirectional Delay Variation TLV [RFC8571], except for that the delay variation is round-trip. 3.4. Round-trip Loss TLV This TLV advertises the round-trip loss for TE Policy. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |A| RESERVED | Loss | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ where: o Type: TBD o Length: 4 o Reserved: Reserved for future use. MUST be set to 0 when sent and MUST be ignored when received. o A: Anomalous (A) Bit. Same with the A Bit in Unidirectional Link Loss TLV [RFC8571]. o Loss: Similar with the Link Loss filed in Unidirectional Link Loss TLV [RFC8571], except for that the loss is round-trip. 4. Security Considerations Procedures and protocol extensions defined in this document do not affect the BGP security model. See the "Security Considerations" section of [RFC4271] for a discussion of BGP security. Also, refer to [RFC4272] and [RFC6952] for analyses of security issues for BGP. Security considerations for acquiring and distributing BGP-LS information are discussed in [RFC9552], [I-D.ietf-idr-bgp-ls-te- path] and [I-D.ietf-idr-bgp-ls-sr-policy]. Lin, et al. Expires March 09, 2025 [Page 6] Internet-Draft BGP-LS TE Policy Performance Metric September 2024 The mechanism proposed in this document is subject to the same vulnerabilities as any other protocol that relies on BGP-LS. 5. Management Considerations An implementation SHOULD allow the operator to specify neighbors to which Link-State NLRIs will be advertised and from which Link-State NLRIs will be accepted. An implementation SHOULD allow the operator to control the content of advertisements, such as whether or not to advertise latency, packet loss rate, bidirectional latency, and bidirectional packet loss rate. An implementation SHOULD allow the operator to control advertisement thresholds to avoid frequent announcements. 6. IANA Considerations This document defines the following TLVs for BGP-LS. TLV Code Point Value -------------------------------------------------------- TBD Round-trip Delay TBD Min/Max Round-trip Delay TBD Round-trip Variation TBD Round-trip Loss 7. References 7.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A Border Gateway Protocol 4 (BGP-4)", RFC 4271, DOI 10.17487/RFC4271, January 2006,. [RFC6952] Jethanandani, M., Patel, K., and L. Zheng, "Analysis of BGP, LDP, PCEP, and MSDP Issues According to the Keying and Authentication for Routing Protocols (KARP) Design Guide", RFC 6952, DOI 10.17487/RFC6952, May 2013, . [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, May 2017 Lin, et al. Expires March 09, 2025 [Page 7] Internet-Draft BGP-LS TE Policy Performance Metric September 2024 [RFC8571] Ginsberg, L., Ed., Previdi, S., Wu, Q., Tantsura, J., and C. Filsfils, "BGP - Link State (BGP-LS) Advertisement of IGP Traffic Engineering Performance Metric Extensions", RFC 8571, DOI 10.17487/RFC8571, March 2019, . [RFC9552] Talaulikar, K., Ed., "Distribution of Link-State and Traffic Engineering Information Using BGP", RFC 9552, DOI 10.17487/RFC9552, December 2023, . [I-D.ietf-idr-bgp-ls-te-path] Previdi, S., Talaulikar, K., Dong, J., Gredler, H., and J. Tantsura, "Advertisement of Traffic Engineering Paths using BGP Link-State", Work in Progress, Internet-Draft, draft-ietf-idr-bgp-ls-te-path-01, September 2023, . [I-D.ietf-idr-bgp-ls-sr-policy] Previdi, S., Talaulikar, K., Dong, J., Gredler, H., and J. Tantsura, "Advertisement of Segment Routing Policies using BGP Link-State", Work in Progress, Internet-Draft, draft-ietf-idr-bgp-ls-sr-policy- 03, November 2023, . Lin, et al. Expires March 09, 2025 [Page 8] Internet-Draft BGP-LS TE Policy Performance Metric September 2024 Authors' Addresses Changwang Lin New H3C Technologies Email: linchangwang.04414@h3c.com Yisong Liu China Mobile Email: liuyisong@chinamobile.com Yongqing Zhu China Telecom Guangzhou Email: zhuyq8@chinatelecom.cn Lin, et al. Expires March 09, 2025 [Page 9]