Bidirectional Forwarding Detection (bfd) ---------------------------------------- Charter Last Modified: 2007-04-02 Current Status: Active Working Group Chair(s): David Ward Jeffrey Haas Routing Area Director(s): Ross Callon David Ward Routing Area Advisor: Ross Callon Technical Advisor(s): Dave Katz Mailing Lists: General Discussion:rtg-bfd@ietf.org To Subscribe: rtg-bfd-request@ietf.org In Body: With a subject line: subscribe Archive: ftp://ftp.ietf.org/ietf-mail-archive/rtg-bfd/ Description of Working Group: The BFD Working Group is chartered to specify a protocol for bidirectional forwarding detection (BFD), as well as extensions to be used within the scope of BFD and IP routing, or protocols such as MPLS that are based on IP routing, in a way that will encourage multiple, inter-operable vendor implementations. BFD is a protocol intended to detect faults in the bidirectional path between two forwarding engines, including physical interfaces, subinterfaces, data link(s), and to the extent possible the forwarding engines themselves, with potentially very low latency. It operates independently of media, data protocols, and routing protocols. An additional goal is to provide a single mechanism that can be used for liveness detection over any media, at any protocol layer, with a wide range of detection times and overhead, to avoid a proliferation of different methods. Important characteristics of BFD include: - Simple, fixed-field encoding to facilitate implementations in hardware - Independence of the data protocol being forwarded between two systems. BFD packets are carried as the payload of whatever encapsulating protocol is appropriate for the medium and network. - Path independence: BFD can provide failure detection on any kind of path between systems, including direct physical links, virtual circuits, tunnels, MPLS LSPs, multihop routed paths, and unidirectional links (so long as there is some return path, of course.) - Ability to be bootstrapped by any other protocol that automatically forms peer, neighbor or adjacency relationships to seed BFD endpoint discovery. At this time the WG is chartered to complete the following work items (additional items will require rechartering): 1. Develop the base BFD protocol specification and submit it to the IESG for publication as a Proposed Standard 2. Document BFD encapsulation and usage profile for single-hop IPv4 and IPv6 adjacencies (e.g, physical links and IP/GRE tunnels for static routes, IS-IS, OSPFv2, OSPFv3, single-hop BGP) and submit the specification to the IESG for publication as a Proposed Standard. 3. Document BFD encapsulation and usage profile for MPLS LSPs and submit the specification to the IESG for publication as a Proposed Standard. 4. Develop the MIB module for BFD and submit it to the IESG for publication as a Proposed Standard. 5. Document BFD encapsulation and usage profile for multi-hop IPv4 and IPv6 adjacencies (e.g. OSPF virtual links and iBGP sessions) and submit the specification to the IESG for publication as a Proposed Standard. Topics for Possible Future Work: 1. Document BFD directly over 802.3 in close collaboration and synchronization with the IEEE. Goals and Milestones: Aug 2004 Submit the base protocol specification to the IESG to be considered as a Proposed Standard. Aug 2004 Submit BFD encapsulation and usage profile for single-hop IPv4 and IPv6 adjacencies to the IESG to be considered as a Proposed Standard Aug 2004 Submit BFD encapsulation and usage profile for MPLS LSPs to the IESG to be considered as a Proposed Standard Nov 2004 Submit BFD MIB to the IESG to be considered as Proposed Standard. Feb 2005 Submit BFD encapsulation and usage profile for multi-hop IPv4 and IPv6 adjacencies to the IESG to be considered as a Proposed Standard Internet-Drafts: Posted Revised I-D Title ------ ------- -------------------------------------------- Jul 2004 Nov 2007 BFD For MPLS LSPs Jul 2004 Jan 2008 Bidirectional Forwarding Detection Jul 2004 Jan 2008 BFD for Multihop Paths Jul 2004 Jan 2008 BFD for IPv4 and IPv6 (Single Hop) Jul 2005 Jan 2008 Generic Application of BFD Request For Comments: None to date.