CDP can pass Riverbed?

[wfqk]

Hi It looks like that CDP can pass Riverbed. I noticed two Cisco device can see each other by CDP when Riverbed sits between the two Cisco devices. In our past knowledge, this could not happen. Anyone can comment on this? Thank you

[Richard Burts · Accepted solution]

I wonder what it was in your past knowledge that indicated that it could not happen. Assuming that this connection is on Ethernet CDP is sent using a specific multicast destination address of 01-00-0c-cc-cc-cc. Devices that understand and process CDP recognize that mac destination address and will process the CDP frame. Devices like Riverbed that do not recognize or process CDP will just see an Ethernet frame with a multicast destination and will forward the frame. This allows two Cisco devices with Riverbed in between to see each other with CDP.

See this page for some additional information about CDP

https://en.wikipedia.org/wiki/Cisco_Discovery_Protocol

HTH

Rick

[wfqk]

Thank you!!