Talk:Cisco Discovery Protocol

Cisco has document online describing CDP frame format of protocol version 1. One can find at Cisco site also additions to the original set of type/length/values online but it's bit harder to find.

But anyway one can't trust the informations provided in the protocol if you can't trust every node on the links. As long as you trust it it's usefull. One can install on non Cisco nodes CDP agents under various operating systems that can use this protocol to advertise itself and provide administrator with additional informations on network topology.

For "free" alternative to discover what informations are advertised by the nodes on the link search www for "cdpr".