BFD for TE supports BFD for TE tunnel and BFD for TE CR-LSP. This section describes BFD for TE tunnel.
The BFD mechanism detects communication faults in links between forwarding engines. The BFD mechanism monitors the connectivity of a data protocol on a bidirectional path between systems. The path can be a physical link or a logical link, for example, a TE tunnel.
BFD detects faults in an entire TE tunnel. If a fault is detected and the primary TE tunnel is enabled with virtual private network (VPN) FRR, a traffic switchover is rapidly triggered, which minimizes the impact on traffic.
On a VPN FRR network, a TE tunnel is established between PEs, and the BFD mechanism is used to detect faults in the tunnel. If the BFD mechanism detects a fault, VPN FRR switching is performed in milliseconds.