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New Member

Cisco voice vlans w/ nortel VOIP system

Hello everyone,

I am going to segment a network with a Nortel VOIP system. Right now, the network is completely flat with PCs plugged into the back of the nortel phones. I would like to set up a voice vlan for the nortel phones but am not sure if voice vlans will work w/ non-cisco phones (cdp). Please provide me some insight if you can. Thanks!


Re: Cisco voice vlans w/ nortel VOIP system

Can you set the switchport up as a dot1q trunk with the data and voice vlan, then on the phone set the vlan for the voice and data? (not that familar with nortel phones). This would be just a trunk then.

The voice vlan option sets the cdp value so that is how cisco phones know what the voice vlan is. In future, LLDP will be useful (new IEEE standard).

New Member

Re: Cisco voice vlans w/ nortel VOIP system

If your are Using Recent Cisco Switches it is quite easy.

Using 4006 SUP III core switches or 3560 PSE's should be okay.

If you have Nortel Phase II phones they can also be powered by the 802.3 cisco switches with no probs.

Anyway set the switchport mode to switchport voice vlan. Set spanning tree portfast and configure qos as you see fit on the port. Configure the voice vlan on the switch eg switchport voice vlan 111. You may need to configure the port to switchport mode dynamic desriable as well. Some older switches may have problems but you can enable trunking to cheat and then a default vlan for the pc on the switchport

As regards to the phones when the phone reboots and you enter the configuration mode via flipping the 4 soft keys. You should then see the vlan option and configure the same vlan number on the phone as the cisco switch eg 111.

The phone should then register again without any problems. All i2002/i2004 firmware for last 2 years has the vlan option. I looked after about 400 nortel phones all on cisco switches of various ages with only minor setting up issues.

Best of luck


Re: Cisco voice vlans w/ nortel VOIP system

has anyone used the "SmartPort" feature on the Cisco Network Assistant? I loaded 4.0 on my laptop to check it out and it can set up the whole swithc for you basically. It does add all these security settings I am not sure of