--- 1/draft-ietf-lsr-ip-flexalgo-00.txt 2021-04-27 09:45:06.422049459 -0700 +++ 2/draft-ietf-lsr-ip-flexalgo-01.txt 2021-04-27 09:45:10.390148141 -0700 @@ -1,23 +1,23 @@ LSR Working Group W. Britto Internet-Draft S. Hegde Intended status: Standards Track P. Kaneriya -Expires: June 26, 2021 R. Shetty +Expires: October 29, 2021 R. Shetty R. Bonica Juniper Networks P. Psenak Cisco Systems - December 23, 2020 + April 27, 2021 IGP Flexible Algorithms (Flex-Algorithm) In IP Networks - draft-ietf-lsr-ip-flexalgo-00 + draft-ietf-lsr-ip-flexalgo-01 Abstract An IGP Flexible Algorithm (Flex-Algorithm) allows IGP to compute constraint-based paths. As currently defined, IGP Flex-Algorithm is used with Segment Routing (SR) data planes - SR MPLS and SRv6. Therefore, Flex-Algorithm cannot be deployed in the absence of SR. This document extends IGP Flex-Algorithm, so that it can be used for regular IPv4 and IPv6 prefixes. This allows Flex-Algorithm to be @@ -31,25 +31,25 @@ 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 June 26, 2021. + This Internet-Draft will expire on October 29, 2021. Copyright Notice - Copyright (c) 2020 IETF Trust and the persons identified as the + 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 include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as @@ -165,21 +165,21 @@ 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 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Algorithm 1 | Algorithm 2 | Algorithm ... | Algorithm n | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 1: ISIS IP Algorithm Sub-TLV - o Type: IP Algorithm Sub-TLV (Value TBD by IANA) + o Type: IP Algorithm Sub-TLV (Value 29) o Length: Variable o Algorithm (1 octet): value from 1 to 255. The IP Algorithm Sub-TLV MUST be propagated throughout the level and MUST NOT be advertised across level boundaries. Therefore, the S bit in the Router Capability TLV, in which the IP Algorithm Sub-TLV is advertised, MUST NOT be set. @@ -282,21 +282,21 @@ 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 |R|R|R|R| MTID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ISIS IPv4 Algorithm Prefix Reachability TLV - o Type: IPv4 Algorithm Prefix Reachability TLV (Value TBD by IANA). + o Type: IPv4 Algorithm Prefix Reachability TLV (Value 126). o Length: variable. o R bits (4 bits): reserved for future use. They MUST be set to zero on transmission and MUST be ignored on receipt. o MTID (12 bits): Multitopology Identifier as defined in [RFC5120]. Note that the value 0 is legal. Followed by one or more prefix entries of the form: @@ -356,21 +356,21 @@ In cases where a prefix advertisement is received in both a IPv4 Prefix Reachability TLV and an IPv4 Algorithm Prefix Reachability TLV, the IPv4 Prefix Reachability advertisement MUST be preferred when installing entries in the forwarding plane. 6.2. The ISIS IPv6 Algorithm Prefix Reachability TLV The ISIS IPv6 Algorithm Prefix Reachability TLV is identical to the ISIS IPv4 Algorithm Prefix Reachability TLV, except that it has a - unique type. The type is TBD by IANA. + unique type. The type is 127. A router receiving multiple IPv6 Algorithm Prefix Reachability advertisements for the same prefix, from the same originator, each with a different Algorithm, MUST select the first advertisement in the lowest-numbered LSP and ignore any subsequent IPv6 Algorithm Prefix Reachability advertisements for the same prefix for any other Algorithm. A router receiving multiple IPv6 Algorithm Prefix Reachability advertisements for the same prefix, from different originators, each @@ -604,34 +604,33 @@ +-------+------------------+---------------------------+ | TBD | IP Algorithm TLV | This Document Section 5.2 | +-------+------------------+---------------------------+ This document also updates the "Sub-TLVs for TLV 242" registry as follows: +-------+----------------------+---------------------------+ | Value | TLV Name | Reference | +-------+----------------------+---------------------------+ - | TBD | IP Algorithm Sub-TLV | This Document Section 5.1 | + | 29 | IP Algorithm Sub-TLV | This Document Section 5.1 | +-------+----------------------+---------------------------+ This document also updates the "ISIS TLV Codepoints Registry" registry as follows: +-------+----------------------------------+------------------------+ | Value | TLV Name | Reference | +-------+----------------------------------+------------------------+ - | TBD | IPv4 Algorithm Prefix | This document, | + | 126 | IPv4 Algorithm Prefix | This document, | | | Reachability TLV | Section 6.1 | - | TBD | IPv6 Algorithm Prefix | This document, | + | 127 | IPv6 Algorithm Prefix | This document, | | | Reachability TLV | Section 6.2 | - | TBD | +-------+----------------------------------+------------------------+ This document updates the "OSPFv2 Extended Prefix Opaque LSA TLVs" registry as follows:: +-------+----------------------------------+------------------------+ | Value | TLV Name | Reference | +-------+----------------------------------+------------------------+ | TBD | OSPFv2 Algorithm Prefix | This Document, | | | Reachability TLV | Section 6.1 | @@ -719,21 +718,21 @@ [RFC8200] Deering, S. and R. Hinden, "Internet Protocol, Version 6 (IPv6) Specification", STD 86, RFC 8200, DOI 10.17487/RFC8200, July 2017, . 14.2. Informative References [I-D.ietf-spring-srv6-network-programming] Filsfils, C., Camarillo, P., Leddy, J., Voyer, D., Matsushima, S., and Z. Li, "SRv6 Network Programming", - draft-ietf-spring-srv6-network-programming-27 (work in + draft-ietf-spring-srv6-network-programming-28 (work in progress), December 2020. [IANA-ALG] IANA, "Sub-TLVs for TLV 242 (IS-IS Router CAPABILITY TLV)", August 1987, . [RFC5286] Atlas, A., Ed. and A. Zinin, Ed., "Basic Specification for IP Fast Reroute: Loop-Free Alternates", RFC 5286, DOI 10.17487/RFC5286, September 2008,