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Bidirectional Forwarding Detection

The information below is for an older approved charter
Document Charter Bidirectional Forwarding Detection WG (bfd) Snapshot
Title Bidirectional Forwarding Detection
Last updated 2004-05-27
State Approved
WG State Active
IESG Responsible AD John Scudder
Charter edit AD (None)
Send notices to (None)

The BFD Working Group is chartered to standardize and support the
  bidirectional forwarding detection protocol (BFD) and its extensions.  A
  core goal of the working group is to standardize BFD in the context of IP
  routing, or protocols such as MPLS that are based on IP routing, in a way
  that will encourage multiple, inter-operable vendor implementations.  The
  Working Group will also provide advice and guidance on BFD to other working
  groups or standards bodies as requested.
  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.
  The working group is chartered to complete the following work items:
  1. Develop the MIB module for BFD and submit it to the IESG for publication
  as a Proposed Standard.
  2a. Provide a generic keying-based cryptographic authentication mechanism for
  the BFD protocol.  This mechanism will support authentication through a key
  identifier for the BFD session's Security Association rather than specifying
  new authentication extensions.
  2b. Provide extensions to the BFD MIB in support of the generic keying-based
  cryptographic authentication mechanism.
  2c. Specify cryptographic authentication procedures for the BFD protocol
  using HMAC-SHA-256 (possibly truncated to a smaller integrity check value)
  using the generic keying-based cryptographic authentication mechanism.
  3. Provide an extension to the BFD core protocol in support of
  point-to-multipoint links and networks.
  4. Provide a mechanism for bootstrapping BFD on dynamically configured edge
  devices using DHCPv4 and DHCPv6.
  5. Assist in the standardization of the BFD protocol for MPLS-TP.  The
  preferred solution will be interoperable with the current BFD specification.
  6. Assist with the standardization of the BFD protocol for Trill.