From: Avner Izhar (aizhar@ccbootcamp.com)
Date: Sat Jan 26 2008 - 05:42:46 ARST
Hi Daniel,
As far as I know, the Cisco ip phones do not support DTP or VTP.
If you connect a phone to a switch that has DTP in dynamic desirable, it will not negotiate a trunk.
The recommended way is to configure an access mode port with a single tagged vlan,
using the 'switchport voice vlan xx' command.
That way you prevent floods, but allow separate vlan for voice and for data.
Some old switches will require a trunk (the XL family of switches), on them it is a good idea to manually allow only two vlans.
HTH,
-------------------------------------------
thanks,
Avner Izhar
CCIE#15999 (Voice), CCVP, CCSI# 31623
Technical Training Manager
CCBOOTCAMP - A Cisco Sponsored Organization (SO)
Email: aizhar@ccbootcamp.com
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-----Original Message-----
From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of Daniel Valle
Sent: Thursday, January 24, 2008 16:02
To: ccielab@groupstudy.com
Subject: IP Phones and trunks.
Hi GS,
I have a question: when an IP phone connects to a switch, by default,
the switch will automatically establish a trunk with the IPphone.
Good. I didn' check that yet, but this makes me conclude tha DTP is
working in the IP phone. Does it also supports VTP ?
To be clearer, If I configure vtp prunning in my switch domain and
later on I plug a IP phone in an interface, is that new trunked
interface prunned by default or will it be receiving
floods/broadcast/multicast unnecessarily ( and so to solve it I make
tune the vlan allowed list )?
Thanks !
Daniel
This archive was generated by hypermail 2.1.4 : Fri Feb 01 2008 - 10:38:01 ARST