The BFD protocol

Kaspersky SD-WAN supports the use of the Bidirectional Forwarding Detection (BFD) protocol for fast (within one second) detection of network connectivity problems on data channels and links. When a problem is detected, BFD relays information about the problem from the data plane to the control plane.

Between BFD peers, a BFD session is established, as part of which they exchange control packets to detect network connectivity problems. If a problem with network connectivity occurs during a BFD session, the routing protocol session is terminated on the corresponding interface of the CPE device, and routing tables are subsequently rebuilt.