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Cisco Discovery Protocol (CDP)

CDP (Cisco Discovery Protocol) is a Cisco proprietary protocol that runs between direct connected network entities (routers, switches, remote access devices, firewalls, etc.). The purpose of the protocol is to supply a network entity with information about its direct connected neighbors.


XXX - add a brief description of CDP history

Protocol dependencies

Example traffic

XXX - Add example traffic here (as plain text or Ethereal screenshot).


The CDP dissector is (fully functional, partially functional, not existing, ... whatever the current state is). Also add info of additional Ethereal features where appropriate, like special statistics of this protocol.

Preference Settings

(XXX add links to preference settings affecting how CDP is dissected).

Example capture file

XXX - Add a simple example capture file to the SampleCaptures page and link from here (see below). Keep this file short, it's also a good idea to gzip it to make it even smaller, as Ethereal can open gzipped files automatically.

Display Filter

A complete list of CDP display filter fields can be found in the [ display filter reference]

Capture Filter

XXX - filter for SNAP OUI/PID pair?