For interest: obviously the phone needs to know the tag number. LLDP-MED
is the "normal" way of signalling this, or CDP on all-Cisco networks.
Responding to the OP, whether you can do this and the syntax to use depends on your switch. For example with 3Com 4400 and (I think) Extreme
x450 you do this:
Tunnel-Type = VLAN, Tunnel-Medium-Type = IEEE-802, Tunnel-Private-Group-id = "20 30t"
...to put vlan 20 untagged and 30 tagged.
I heard that cisco doesn't "do" lldp-med yet. Thanks for the info i'll try this and let you know. I'm currently running an all procurve network with 3500yl switches. I am told that with newest firmware this should be possible. "This e-mail is property of the company and is supposed to contain only professional content. The company can at all times consult the content of this e-mail and the reply to this e-mail. By replying to this e-mail, you confirm your explicit agreement with the preceding." "Deze e-mail is het eigendom van de Vennootschap en wordt verondersteld enkel beroepsmatige informatie te bevatten. De Vennootschap kan ten allen tijden de inhoud van deze e-mail en van het antwoord daarop raadplegen. Door het beantwoorden van deze e-mail bevestigt U uitdrukkelijk uw akkoord met het voorafgaande."