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New User
Posts: 2
Registered: ‎02-21-2010
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Cisco CDP

Hi All,


Does EX4200 support CDP protcol to discover the IP phones automatically?


if no, are there any alternatives other than the LLDP?

Distinguished Expert
Posts: 493
Registered: ‎06-30-2009
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Re: Cisco CDP



EX-series and any other Juniper products do not support CDP. The only standard-based alternative is LLDP-MED.


Kind Regards

Michael Pergament


If this worked for you please flag my post as an "Accepted Solution" so others can benefit. A kudo would be cool if you think I earned it.

Posts: 19
Registered: ‎01-06-2010
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Re: Cisco CDP

Hi Junos-A

     My organization is in the process of deploying EX4200 chassis switches in the IDFs and have found that the more recent firware for Cisco phones (can be found on CUCM as of 7, I believe) supports LLDP for the phones just fine.  If you're running older firmware, you need to upgrade the phones first before being able to use them on Juniper switches with dynamic VLAN assignments.  I've found that configuring swithports as trunks and pointing the phones to a CUCM cluster with the appropriate firmware as all that's needed to get the phones prepped.


     An alternative is to configure Juniper switchports as trunks and assisgning a native VLAN (for the phone) and have membership to the data vlan.

Trusted Contributor
Posts: 92
Registered: ‎10-17-2008
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Re: Cisco CDP

none...LLDP-MED is the only option..i guess if you're looking to buy large quantities of ex-4200..they might get juiper to emulate CDP somehow

Posts: 73
Registered: ‎02-17-2009
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Re: Cisco CDP

I have seen HP Procurve switches which support CDP, but they cannot be used to assign data and voice vlan to the phone. So the only possible option is to upgrade the phones to firmware which support LLDP , otherwise i dont think there is any feasible workaround for this.