You are viewing an old version of this page. View the current version.

Compare with Current View Page History

« Previous Version 2 Next »

Summary

Bidirectional Forwarding Detection (BFD) is a low-overhead and short-duration protocol intended to detect faults in the bidirectional path between two forwarding engines, including physical interfaces, sub-interfaces, 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.

BFD is basically a hello protocol for checking bidirectional neighbor reachability. It provides sub-second link failure detection support. BFD is not routing protocol specific, unlike protocol hello timers or such.

BFD Control packets is transmitted in UDP packets with destination port 3784, BFD also uses port 4784 for multihop paths. Source port is in the range 49152 through 65535. And BFD Echo packets are encapsulated in UDP packet with destination port 3785.

Standards and Technologies:

  • RFC 5880 Bidirectional Forwarding Detection (BFD)
  • RFC 5881 BFD for IPv4 and IPv6
  • RFC 5882 Generic Application of BFD
  • RFC 5883 Bidirectional Forwarding Detection (BFD) for Multihop Paths


  • No labels