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New Member

Daisy-chained IP Phone/PC Question

1) With a PC connected to the network via a IP Phone, if the IP Phone fails, will the PC still be connected to the Network/Switch Port which is configured as a trunk port?

2) Similarly, if the IP Phone is disconnected from the Switch Port (trunk port) and a PC is directly connected to this port, will the PC be connected to the network with the appropriate VLAN that is originally configured for the data PC.

New Member

Re: Daisy-chained IP Phone/PC Question

1) As long as the phone has power and it isn't the switch component that has failed then the PC maintains it's network connection even if the phone cannot register with CallManager.

2) That packets from the PC are not tagged with VLAN information so they are seen at the switch as arriving on the native/untagged 802.1Q VLAN which is normally the data VLAN. The phones send tagged 802.1Q packets for the voice VLAN.

This means that phones and PCs can be swapped on the switch ports and still arrive on the correct VLAN.