Basic Cisco 7960 Phone Question

[cableip]

Hi, folks:

I am new to Cisco VoIP solution. I would like to set up a Cisco 7960 phone. When I provisioned the phone, I noticed that there is a parameter called "Admin VLAN ID".

Since my phone is connected to an access port of a switch, I believe it should not use any VLAN tagging.

So I am wondering whether this vlan tagging is only applied when a PC is subtended to the phone? If the PC belongs to a different VLAN, does it automatically change the connection to the switch to VLAN trunking?

If no PC is subtended to the phone, then, does the phone automatically turn off VLAN tagging?

I saw the phone got IP address from the local DHCP server, however, I cannot ping it. So does Cisco phone rejects ICMP packet by default?

Thanks a lot!

Shixiong

[nates]

The "Cisco" solution to your problem would be to segment your voice and data networks and run QOS on the network to preserve voice quality. A typical Cisco switch port would look like this.

interface GigabitEthernet0/4

switchport trunk encapsulation dot1q

switchport mode trunk

switchport voice vlan 10

srr-queue bandwidth share 10 10 60 20

srr-queue bandwidth shape 10 0 0 0

queue-set 2

mls qos trust device cisco-phone

mls qos trust cos

no mdix auto

auto qos voip cisco-phone

spanning-tree portfast

!

This config would put a phone in VLAN 10 and either a directly attached PC or a PC hanging off the phone into VLAN 1. You would be responsible for making sure the proper routing and DHCP are available for both your Voice and Data network.

If you are just playing around and want to get a 7960 to work in the data network, remove all trunking info and voice vlan info and the phone should boot up with the same IP scheme as a PC on the data network (make sure this DHCP scope has correct option 150 settings - or this test will be very un-eventful for you - phone will not get a config.)

ICMP is not disabled by default, but if you have a phone that thinks it is in the voice vlan (called admin vlan on phone) but an address on the data network, it isn't going to work.

-nate