Analysis Of Bidirectional Forwarding Detection

IP networks were not designed to repair failures in sub-second intervals, but applications such as VoIP increasingly are driving the need for rapid failure detection and correction. Traditional routing infrastructure has been limited in meeting the failure-resolution requirements of real-time applications such as voice.Bidirectional Forwarding Detection (BFD) , is helping to overcome these limitations and increase the speed of failure detection and recovery. BFD provides a simple, lightweight and abstract method of detecting the ability of links or systems to forward traffic. This article analysis BFD's state machine, state variable, function module and package format in detail. BFD's co(?)peration with unicast routing protocols, MPLS, and tunnel technology is also considered deeply in this article.BFD is still an IETF draft standard, and there are some problems with BFD. This article gives a brief introduction about these problems as well as some suggestions to overcome them.