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A voice vlan port must be a trunk?

Hi all,

I had saw some discuss in other forum said that a voice vlan port in 3550 must be a trunk port, and the data traffic vlan should be the native vlan of the trunk. But some body that the port need not be a trunk. Also the doc of 3550 does not say that the port must be a trunk. And I tried to use command "switchport mode access" "switchport access vlan x" "switchport voice vlan y" in a same port and there is no error. but at that time when I try to use command "show vlan" to verify the config, the display just showed that the port is in vlan x. Is there any body knows the answer? And can I use "switchport mode access" in a voice vlan port? Thank You!

Best Regards

Teru Lei


Re: A voice vlan port must be a trunk?


I've heard that Cisco phones can act as a mini-switch, taking an ethernet connection from the network, and providing an ethernet connection to the desktop. This allows both voice and data to ride the same network connection. The way that the phone differentiates between voice and data is by accepting a trunk from the network, switching data from the data VLAN to the data port, and keeping traffic in the voice VLAN for itself. This would only be necessary if your VOIP design includes separate network lines for voice and data.



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