Voice Vlan = trunk + BPDUGuard?

Unanswered Question
Aug 10th, 2009
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I haven't sniffed the data yet to see what's going on - but it's my understanding that the "switchport voice vlan" command works in conjunction with CDP. When a phone is detected, the switch establishes a 'lite' trunk with the phone, passing both voice and data VLANs.

Is this trunk maintained without any BPDUs? How does that work, exactly?

If I have BPDUGuard on my access ports, does it just 'ignore' bpdu's related to Voice-VLAN related trunks, or does this trunk really exist without BPDUs?

if so... how?

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ivillegas Fri, 08/14/2009 - 06:00
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BPDU can only be received on a port existing on the trunk. If a BPDU is received on a VLAN that is not configured on the trunk/voice port, it will be dropped and will not trigger bpduguard.


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