IDR Working Group J. Tantsura Internet-Draft Juniper Networks Intended status: Standards Track Z. Wang Expires: December 6, 2021 Q. Wu Huawei K. Talaulikar Cisco Systems June 4, 2021 Distribution of Traffic Engineering Extended Administrative Groups using BGP-LS draft-ietf-idr-eag-distribution-19 Abstract Administrative groups are link attributes used for traffic engineering. This document defines an extension to BGP-LS for advertisement of extended administrative groups (EAGs). 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 6, 2021. Copyright Notice Copyright (c) 2021 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 Tantsura, et al. Expires December 6, 2021 [Page 1] Internet-Draft Extended Administrative Group June 2021 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 . . . . . . . . . . . . . . . . . . . . . . . . 2 1.1. Requirements Language . . . . . . . . . . . . . . . . . . 2 2. Advertising Extended Administrative Group in BGP-LS . . . . . 3 3. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 3 4. Manageability Considerations . . . . . . . . . . . . . . . . 4 5. Security Considerations . . . . . . . . . . . . . . . . . . . 4 6. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 5 7. References . . . . . . . . . . . . . . . . . . . . . . . . . 5 7.1. Normative References . . . . . . . . . . . . . . . . . . 5 7.2. Informative References . . . . . . . . . . . . . . . . . 5 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 6 1. Introduction Administrative groups (commonly referred to as "colors" or "link colors") are link attributes that are advertised by link state protocols like IS-IS [RFC1195], OSPFv2 [RFC2328] and OSPFv3 [RFC5340]. The BGP-LS advertisement of the originally defined (non- extended) administrative groups is encoded using the Administrative Group (color) TLV 1088 as defined in [RFC7752]. These administrative groups are defined as a fixed-length 32-bit bitmask. As networks grew and more use-cases were introduced, the 32-bit length was found to be constraining and hence extended administrative groups (EAG) were introduced in [RFC7308]. The EAG TLV (Section 2) is not a replacement for the Administrative Group (color) TLV; as explained in [RFC7308] both values can coexist. It is out of scope for this document to specify the behavior of the BGP-LS consumer [RFC7752]. This document specifies an extension to BGP-LS for advertisement of the extended administrative groups. 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. Tantsura, et al. Expires December 6, 2021 [Page 2] Internet-Draft Extended Administrative Group June 2021 2. Advertising Extended Administrative Group in BGP-LS This document defines an extension that enables BGP-LS speakers to signal the EAG of links in a network to a BGP-LS consumer of network topology such as a centralized controller. The centralized controller can leverage this information in traffic engineering computations and other use-cases. When a BGP-LS speaker is originating the topology learnt via link-state routing protocols like OSPF or IS-IS, the EAG information of the links is sourced from the underlying extensions as defined in [RFC7308]. The EAG of a link is encoded in a new Link Attribute TLV [RFC7752] using the following format: 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 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Extended Administrative Group (variable) // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 1: Extended Administrative Group TLV Format Where: o Type: 1173 o Length: variable length which represents the total length of the value field in octets. The length value MUST be a multiple of 4. If the length is not a multiple of 4, the TLV MUST be considered malformed. o Value: one or more sets of 32-bit bitmasks that indicate the administrative groups (colors) that are enabled on the link when those specific bits are set. 3. IANA Considerations This document requests assigning a code-point from the registry "BGP- LS Node Descriptor, Link Descriptor, Prefix Descriptor, and Attribute TLVs" based on table below. Early allocation for these code-points have been done by IANA. Tantsura, et al. Expires December 6, 2021 [Page 3] Internet-Draft Extended Administrative Group June 2021 +------------+-------------------------------+-------------------+ | Code Point | Description | IS-IS TLV/Sub-TLV | +------------+-------------------------------+-------------------+ | 1173 | Extended Administrative Group | 22/14 | +------------+-------------------------------+-------------------+ 4. Manageability Considerations The new protocol extensions introduced in this document augment the existing IGP topology information that is distributed via [RFC7752]. Procedures and protocol extensions defined in this document do not affect the BGP protocol operations and management other than as discussed in the Manageability Considerations section of [RFC7752]. Specifically, the malformed attribute tests for syntactic checks in the Fault Management section of [RFC7752] now encompass the new BGP- LS Attribute TLV defined in this document. The semantic or content checking for the TLV specified in this document and its association with the BGP-LS NLRI types or its BGP-LS Attribute is left to the consumer of the BGP-LS information (e.g. an application or a controller) and not the BGP protocol. A consumer of the BGP-LS information retrieves this information over a BGP-LS session (refer Section 1 and 2 of [RFC7752]). 5. Security Considerations The 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. This document only introduces a new Attribute TLV and any syntactic error in it would result in the BGP-LS Attribute being discarded [RFC7752]. 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 [RFC7752]. The TLV introduced in this document is used to propagate the EAG extensions defined in [RFC7308]. It is assumed that the IGP instances originating this TLV will support any required security mechanisms for OSPF and IS-IS, in order to prevent any security issues when propagating the Sub-TLVs into BGP-LS. Security concerns for OSPF are addressed in [RFC7474], [RFC4552] and [RFC7166]. Further security analysis for OSPF protocol is done in [RFC6863]. Security considerations for IS-IS are specified by [RFC5304]. Tantsura, et al. Expires December 6, 2021 [Page 4] Internet-Draft Extended Administrative Group June 2021 The advertisement of the link attribute information defined in this document presents no significant additional risk beyond that associated with the existing link attribute information already supported in [RFC7752]. 6. Acknowledgments The authors would like to thank Eric Osborne, Les Ginsberg, Tim Chown, Ben Niven-Jenkins and Alvaro Retana for their reviews and valuable comments. 7. References 7.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . [RFC7308] Osborne, E., "Extended Administrative Groups in MPLS Traffic Engineering (MPLS-TE)", RFC 7308, DOI 10.17487/RFC7308, July 2014, . [RFC7752] Gredler, H., Ed., Medved, J., Previdi, S., Farrel, A., and S. Ray, "North-Bound Distribution of Link-State and Traffic Engineering (TE) Information Using BGP", RFC 7752, DOI 10.17487/RFC7752, March 2016, . [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017, . 7.2. Informative References [RFC1195] Callon, R., "Use of OSI IS-IS for routing in TCP/IP and dual environments", RFC 1195, DOI 10.17487/RFC1195, December 1990, . [RFC2328] Moy, J., "OSPF Version 2", STD 54, RFC 2328, DOI 10.17487/RFC2328, April 1998, . Tantsura, et al. Expires December 6, 2021 [Page 5] Internet-Draft Extended Administrative Group June 2021 [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, . [RFC4272] Murphy, S., "BGP Security Vulnerabilities Analysis", RFC 4272, DOI 10.17487/RFC4272, January 2006, . [RFC4552] Gupta, M. and N. Melam, "Authentication/Confidentiality for OSPFv3", RFC 4552, DOI 10.17487/RFC4552, June 2006, . [RFC5304] Li, T. and R. Atkinson, "IS-IS Cryptographic Authentication", RFC 5304, DOI 10.17487/RFC5304, October 2008, . [RFC5340] Coltun, R., Ferguson, D., Moy, J., and A. Lindem, "OSPF for IPv6", RFC 5340, DOI 10.17487/RFC5340, July 2008, . [RFC6863] Hartman, S. and D. Zhang, "Analysis of OSPF Security According to the Keying and Authentication for Routing Protocols (KARP) Design Guide", RFC 6863, DOI 10.17487/RFC6863, March 2013, . [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, . [RFC7166] Bhatia, M., Manral, V., and A. Lindem, "Supporting Authentication Trailer for OSPFv3", RFC 7166, DOI 10.17487/RFC7166, March 2014, . [RFC7474] Bhatia, M., Hartman, S., Zhang, D., and A. Lindem, Ed., "Security Extension for OSPFv2 When Using Manual Key Management", RFC 7474, DOI 10.17487/RFC7474, April 2015, . Authors' Addresses Tantsura, et al. Expires December 6, 2021 [Page 6] Internet-Draft Extended Administrative Group June 2021 Jeff Tantsura Juniper Networks Email: jefftant.ietf@gmail.com Zitao Wang Huawei 101 Software Avenue, Yuhua District Nanjing, Jiangsu 210012 China Email: wangzitao@huawei.com Qin Wu Huawei 101 Software Avenue, Yuhua District Nanjing, Jiangsu 210012 China Email: bill.wu@huawei.com Ketan Talaulikar Cisco Systems Email: ketant@cisco.com Tantsura, et al. Expires December 6, 2021 [Page 7]