And here I thought only Cisco equipment used CDP

Turns out polycom phones use this protocol as well... You know, the one that I assumed was proprietary. Based on that assumption, I made another assumption that it would not be an issue to run them in parallel to the replacement Cisco phones. Boy was I wrong! After adding the new voice vlan, these older polycom phones reregistered with their phone server using the newly created subnet. This caused the address space to deplete and the new phones could not register due to a lack of addresses. Lesson learned. DO NOT ASSUME ANYTHING IN THIS FIELD! I'll admit that it was fun to troubleshoot this issue (I wasn't the one who put this together).

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Comments

it_consultant

Cisco must have released an API for CDP because a lot of non-Cisco equipment is capable of using CDP. I run CDP/FDP in my Brocade environment (Cisco phones and BNA uses CDP, FDP, or LLDP to create graphical maps) because it is easier than LLDP, although I think LLDP will give you better information if you bother to set it up.

WafflesAndRootbeer

It's reverse engineered and spoofed to allow mixed vendor networks as Cisco-Only isn't practical for everyone. A few of their competitors have dropped CDP from their products though CDP is still functional to a certain degree.

CodeBlox

I was gonna say... I could probably reverse engineer it using wireshark and whip something up in C to have my desktop speak CDP.

EV42TMAN

its available on VMware ESXi too. you can see which switch/port that you virtual switches are plugged into.

Cdp is so yesterday.

Yeah OK buddy.

LLDP is the new CDP.

Why cant I get my Mitel phones to pick up VLAN assignment using CDP from a cisco switch, its a conspisory I tell you!!

networkjutsu

Even though we use Cisco phones here, we disabled CDP on our switches and use LLDP.