BFD – Bidirectional Forwarding Detection

What is one pain-in-the-butt thing with wireless links connected to a Ethernet port on a Cisco router?
You don’t know when the wireless link goes down?

Since Ethernet technology does not provide for end-to-end connectivity checks, like ATM OAM F5, Frame-Relay EEK, or PPP LCP Keepalive, you need a similar method to know when the wireless link or the remote site is unreachable.

There are varies workarounds, eg using IP SLA monitor, or using BGP with reduced timers. A better solution is to use Bidirectional Forwarding Detection (BFD), to quickly identify the failing wireless VLANs and route your retraffic quickly and efficiently.

Continue reading “BFD – Bidirectional Forwarding Detection”