--- 1/draft-ietf-bfd-seamless-use-case-02.txt 2015-07-31 10:14:57.900608395 -0700 +++ 2/draft-ietf-bfd-seamless-use-case-03.txt 2015-07-31 10:14:57.924608967 -0700 @@ -1,25 +1,25 @@ -Network Working Group A. Aldrin -Internet-Draft +Network Working Group S. Aldrin +Internet-Draft Google, Inc Intended status: Informational M. Bhatia -Expires: October 30, 2015 Ionos Networks +Expires: February 1, 2016 Ionos Networks S. Matsushima Softbank G. Mirsky Ericsson N. Kumar Cisco - April 28, 2015 + July 31, 2015 Seamless Bidirectional Forwarding Detection (BFD) Use Case - draft-ietf-bfd-seamless-use-case-02 + draft-ietf-bfd-seamless-use-case-03 Abstract This document provides various use cases for Bidirectional Forwarding Detection (BFD) such that extensions could be developed to allow for simplified detection of forwarding failures. Status of This Memo This Internet-Draft is submitted in full conformance with the @@ -28,21 +28,21 @@ 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 http://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 October 30, 2015. + This Internet-Draft will expire on February 1, 2016. Copyright Notice Copyright (c) 2015 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 (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents @@ -56,30 +56,32 @@ 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3 2. Introduction to Seamless BFD . . . . . . . . . . . . . . . . 3 3. Use Cases . . . . . . . . . . . . . . . . . . . . . . . . . . 4 3.1. Unidirectional Forwarding Path Validation . . . . . . . . 4 3.2. Validation of forwarding path prior to traffic switching 5 3.3. Centralized Traffic Engineering . . . . . . . . . . . . . 5 3.4. BFD in Centralized Segment Routing . . . . . . . . . . . 6 3.5. BFD Efficient Operation Under Resource Constraints . . . 6 - 3.6. BFD for Anycast Address . . . . . . . . . . . . . . . . . 6 + 3.6. BFD for Anycast Address . . . . . . . . . . . . . . . . . 7 3.7. BFD Fault Isolation . . . . . . . . . . . . . . . . . . . 7 3.8. Multiple BFD Sessions to Same Target . . . . . . . . . . 7 3.9. MPLS BFD Session Per ECMP Path . . . . . . . . . . . . . 7 4. Security Considerations . . . . . . . . . . . . . . . . . . . 8 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8 6. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 8 7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 9 - 8. Normative References . . . . . . . . . . . . . . . . . . . . 9 - Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 9 + 8. References . . . . . . . . . . . . . . . . . . . . . . . . . 9 + 8.1. Normative References . . . . . . . . . . . . . . . . . . 9 + 8.2. Informative References . . . . . . . . . . . . . . . . . 10 + Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 10 1. Introduction Bidirectional Forwarding Detection (BFD) is a lightweight protocol, as defined in [RFC5880], used to detect forwarding failures. Various protocols and applications rely on BFD for failure detection. Even though the protocol is simple and lightweight, there are certain use cases, where faster setting up of sessions and continuity check of the data forwarding paths is necessary. This document identifies use cases such that necessary enhancements could be made to BFD protocol @@ -103,26 +105,27 @@ enhancement proposals are outside the scope of this document as well. 1.1. Terminology The reader is expected to be familiar with the BFD, IP, MPLS and Segment Routing (SR) terminology and protocol constructs. This section identifies only the new terminology introduced. 2. Introduction to Seamless BFD - BFD, as defined in standard [RFC5880], requires two network nodes, to - exchange locally allocated discriminators. The discriminator enables + BFD, as defined in [RFC5880], requires two network nodes, to exchange + locally allocated discriminators. The discriminator enables identification of the sender and receiver of BFD packets of the particular session and proactive continuity monitoring of the forwarding path between the two. [RFC5881] defines single hop BFD - whereas [RFC5883] and [RFC5884] defines multi-hop BFD. + whereas [RFC5883] defines multi-hop BFD, [RFC5884] BFD for MPLS + LSPs, and [RFC5885] - BFD for PWs. Currently, BFD is best suited to verify that two end points are reachable or that an existing connection continues to be valid. In order for BFD to be able to initially verify that a connection is valid and that it connects the expected set of end points, it is necessary to provide the node information associated with the connection at each end point prior to initiating BFD sessions, such that this information can be used to verify that the connection is valid. @@ -368,70 +372,89 @@ Email: gh1691@att.com Santosh P K Juniper Email: santoshpk@juniper.net Mach Chen - Huawei Email: mach.chen@huawei.com Nobo Akiya + Cisco Systems Email: nobo@cisco.com 7. Acknowledgements The authors would like to thank Eric Gray for his useful comments. -8. Normative References +8. References - [I-D.geib-spring-oam-usecase] - ?, "Geib, R., Filsfils, C., Pignataro, C. and Kumar, N., - "SR MPLS monitoring use case", draft-geib-spring-oam- - usecase-03(work in progress), October 2014.", 1900. +8.1. Normative References [RFC4379] Kompella, K. and G. Swallow, "Detecting Multi-Protocol Label Switched (MPLS) Data Plane Failures", RFC 4379, - February 2006. + DOI 10.17487/RFC4379, February 2006, + . [RFC5880] Katz, D. and D. Ward, "Bidirectional Forwarding Detection - (BFD)", RFC 5880, June 2010. + (BFD)", RFC 5880, DOI 10.17487/RFC5880, June 2010, + . [RFC5881] Katz, D. and D. Ward, "Bidirectional Forwarding Detection - (BFD) for IPv4 and IPv6 (Single Hop)", RFC 5881, June - 2010. + (BFD) for IPv4 and IPv6 (Single Hop)", RFC 5881, + DOI 10.17487/RFC5881, June 2010, + . [RFC5883] Katz, D. and D. Ward, "Bidirectional Forwarding Detection - (BFD) for Multihop Paths", RFC 5883, June 2010. + (BFD) for Multihop Paths", RFC 5883, DOI 10.17487/RFC5883, + June 2010, . [RFC5884] Aggarwal, R., Kompella, K., Nadeau, T., and G. Swallow, "Bidirectional Forwarding Detection (BFD) for MPLS Label - Switched Paths (LSPs)", RFC 5884, June 2010. + Switched Paths (LSPs)", RFC 5884, DOI 10.17487/RFC5884, + June 2010, . + + [RFC5885] Nadeau, T., Ed. and C. Pignataro, Ed., "Bidirectional + Forwarding Detection (BFD) for the Pseudowire Virtual + Circuit Connectivity Verification (VCCV)", RFC 5885, + DOI 10.17487/RFC5885, June 2010, + . + +8.2. Informative References + + [I-D.geib-spring-oam-usecase] + Geib, R., Filsfils, C., Pignataro, C., and N. Kumar, "Use + case for a scalable and topology aware MPLS data plane + monitoring system", draft-geib-spring-oam-usecase-06 (work + in progress), July 2015. Authors' Addresses Sam Aldrin - 2330 Central Expressway + Google, Inc + 1600 Amphitheatre Parkway + Mountain View, CA Email: aldrin.ietf@gmail.com Manav Bhatia Ionos Networks Email: manav@ionosnetworks.com + Satoru Matsushima Softbank Email: satoru.matsushima@g.softbank.co.jp Greg Mirsky Ericsson Email: gregory.mirsky@ericsson.com