The firewall supports Bidirectional Forwarding Detection (BFD),
a protocol that recognizes a failure in the bidirectional path between
two routing peers. BFD failure detection is extremely fast, providing
for a faster failover than can be achieved by link monitoring or
frequent dynamic routing health checks, such as Hello packets or
heartbeats. Mission-critical data centers and networks that require high
availability and extremely fast failover need the extremely fast
failure detection that BFD provides.