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IP Phone and VT Advantage


not sure of what is going on because the phones were working when we tested a month ago. anyhow i have 7961 and 7941 phones connected and we are using the vt cams and the vt advantage software. im getting no phone present but if i use ip communicator it works fine.

all phones have the latest loads SCCP41.8-2-2SR2S (this one is what i have for the 7961).

any assistance would be appreciated.

PS. they are connected to a 3750 10/100 poe.


Re: IP Phone and VT Advantage

Hi friend, are you using VLANS?, if yes, make sure that the data vlan can reach the voice vlan.

All the best


Cisco Employee

Re: IP Phone and VT Advantage


Also make sure that CDP is enabled on the phones.


Re: IP Phone and VT Advantage


ive verified those things previous to posting and they are all good. firewall may be the issue here although everything was working fine for a demo we did a couple of months ago before they bought the product.

what are the port type and numbers i should look for from the firewall side?

thanks in advance


Re: IP Phone and VT Advantage

Hi, the protocols used by Cisco VTA are:

- Cisco Discovery Protocol: Discovery between IP phone and PC

- Cisco Audio Session Tunnel: Association and signaling between

IP phone and Cisco Unified Video Advantage software. TCP port 4224

- SCCP: Signaling between IP phone and Unified CM. TCP port 2000

- RTP: Media transport (video to Cisco Unified Video Advantage,

audio to phone). UDP 16384 to 32767.

All the best



Re: IP Phone and VT Advantage

david thanks

ill advise if i have a solution and/or what i was doing incorrectly.

thanks again


Re: IP Phone and VT Advantage

just to advise that the firewall was the cause of this issue. this was my first recommendation but the firewall administrators advised that it was not on thier side. after much testing i brought in another firewall person and they resolved issue as being an issue with NAT between two networks.

Glad we got this working..thanks in advance.

PS as you might have gathered its a firewall centric network just in case you guys were wondering :)