--- 1/draft-ietf-ospf-mpls-elc-14.txt 2020-06-01 02:13:09.321495100 -0700 +++ 2/draft-ietf-ospf-mpls-elc-15.txt 2020-06-01 02:13:09.341495608 -0700 @@ -1,26 +1,26 @@ LSR Working Group X. Xu Internet-Draft Alibaba Inc Intended status: Standards Track S. Kini -Expires: November 29, 2020 +Expires: December 3, 2020 P. Psenak C. Filsfils S. Litkowski Cisco Systems, Inc. M. Bocci Nokia - May 28, 2020 + June 1, 2020 Signaling Entropy Label Capability and Entropy Readable Label Depth Using OSPF - draft-ietf-ospf-mpls-elc-14 + draft-ietf-ospf-mpls-elc-15 Abstract Multiprotocol Label Switching (MPLS) has defined a mechanism to load- balance traffic flows using Entropy Labels (EL). An ingress Label Switching Router (LSR) cannot insert ELs for packets going into a given Label Switched Path (LSP) unless an egress LSR has indicated via signaling that it has the capability to process ELs, referred to as the Entropy Label Capability (ELC), on that LSP. In addition, it would be useful for ingress LSRs to know each LSR's capability for @@ -37,21 +37,21 @@ 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 November 29, 2020. + This Internet-Draft will expire on December 3, 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 @@ -59,21 +59,21 @@ 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. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 3. Advertising ELC Using OSPF . . . . . . . . . . . . . . . . . 3 - 3.1. Advertising ELC Using OSPFv2 . . . . . . . . . . . . . . 4 + 3.1. Advertising ELC Using OSPFv2 . . . . . . . . . . . . . . 3 3.2. Advertising ELC Using OSPFv3 . . . . . . . . . . . . . . 4 4. Advertising ERLD Using OSPF . . . . . . . . . . . . . . . . . 4 5. Signaling ELC and ERLD in BGP-LS . . . . . . . . . . . . . . 5 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 5 7. Security Considerations . . . . . . . . . . . . . . . . . . . 5 8. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 6 9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 6 10. References . . . . . . . . . . . . . . . . . . . . . . . . . 6 10.1. Normative References . . . . . . . . . . . . . . . . . . 6 10.2. Informative References . . . . . . . . . . . . . . . . . 8 @@ -123,20 +123,30 @@ originator. Similarly, in a multi domain network, the identity of the prefix originator and its capabilities may not be known to the ingress LSR. If a router has multiple interfaces, the router MUST NOT announce ELC unless all of its interfaces are capable of processing ELs. If the router supports ELs on all of its interfaces, it SHOULD advertise the ELC with every local host prefix it advertises in OSPF. +3.1. Advertising ELC Using OSPFv2 + + [RFC7684] defines the OSPFv2 Extended Prefix TLV to advertise + additional attributes associated with a prefix. The OSPFv2 Extended + Prefix TLV includes a one-octet Flags field. A new flag in the Flags + field is used to signal the ELC for the prefix: + + 0x20 - E-Flag (ELC Flag): Set by the advertising router to + indicate that the prefix originator is capable of processing ELs. + The ELC signaling MUST be preserved when an OSPF Area Border Router (ABR) distributes information between areas. To do so, an ABR MUST originate an OSPFv2 Extended Prefix Opaque LSA [RFC7684] including the received ELC setting. When an OSPF Autonomous System Boundary Router (ASBR) redistributes a prefix from another instance of OSPF or from some other protocol, it SHOULD preserve the ELC signaling for the prefix if it exists. To do so, an ASBR SHOULD originate an Extended Prefix Opaque LSA [RFC7684] including the ELC setting of the redistributed prefix. The flooding @@ -135,34 +145,23 @@ originate an OSPFv2 Extended Prefix Opaque LSA [RFC7684] including the received ELC setting. When an OSPF Autonomous System Boundary Router (ASBR) redistributes a prefix from another instance of OSPF or from some other protocol, it SHOULD preserve the ELC signaling for the prefix if it exists. To do so, an ASBR SHOULD originate an Extended Prefix Opaque LSA [RFC7684] including the ELC setting of the redistributed prefix. The flooding scope of the Extended Prefix Opaque LSA MUST match the flooding scope of the LSA that an ASBR originates as a result of the redistribution. - The exact mechanism used to exchange ELC between protocol instances on an ASBR is outside of the scope of this document. -3.1. Advertising ELC Using OSPFv2 - - [RFC7684] defines the OSPFv2 Extended Prefix TLV to advertise - additional attributes associated with a prefix. The OSPFv2 Extended - Prefix TLV includes a one-octet Flags field. A new flag in the Flags - field is used to signal the ELC for the prefix: - - 0x20 - E-Flag (ELC Flag): Set by the advertising router to - indicate that the prefix originator is capable of processing ELs. - 3.2. Advertising ELC Using OSPFv3 [RFC5340] defines the OSPFv3 PrefixOptions field to indicate capabilities associated with a prefix. A new bit in the OSPFv3 PrefixOptions is used to signal the ELC for the prefix: 0x40 - E-Flag (ELC Flag): Set by the advertising router to indicate that the prefix originator is capable of processing ELs. The ELC signaling MUST be preserved when an OSPFv3 Area Border @@ -283,21 +282,21 @@ Tantsura, J., Chunduri, U., Talaulikar, K., Mirsky, G., and N. Triantafillis, "Signaling MSD (Maximum SID Depth) using Border Gateway Protocol - Link State", draft-ietf- idr-bgp-ls-segment-routing-msd-18 (work in progress), May 2020. [I-D.ietf-isis-mpls-elc] Xu, X., Kini, S., Psenak, P., Filsfils, C., Litkowski, S., and M. Bocci, "Signaling Entropy Label Capability and Entropy Readable Label Depth Using IS-IS", draft-ietf- - isis-mpls-elc-12 (work in progress), April 2020. + isis-mpls-elc-13 (work in progress), May 2020. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . [RFC5340] Coltun, R., Ferguson, D., Moy, J., and A. Lindem, "OSPF for IPv6", RFC 5340, DOI 10.17487/RFC5340, July 2008, .