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New Member

IP phone integration,qos

Dear All,

We are planning to implement IP phones in our network(attached the switch-diagram). Right now we have the following switches configured as our Access layer switches.all are cisco 2950 switches but in some switches there is a slight change in the IOS version. all switches are configured as VTP client.

We have only one Core & Distribution switch serve in our network which is a 4507 Switch.this switch has been configured as VTP server.Intervlan communication is happening through this switch.(IOS (tm) Catalyst 4000 L3 Switch Software (cat4000-I5S-M), Version 12.2(20)EWA,cisco WS-C4507R (MPC8245)

Right now clients are connected to this access layer switches and receiving ip through DHCP server which is our active directory.while configuring voice vlan can we still use our active directory as our DHCP server for this vlan? is a native Vlan must for Voice traffic? any changes or modification needed in current spanning-tree configuration.

Can we implement IP phones in the following switches and configure QOS for this voice traffic.Can i have some sample configurations and design docs.

5th floor-01


IOS (tm) C2950 Software (C2950-I6Q4L2-M), Version 12.1(13)EA

Model number: WS-C2950G-48-EI

5th Floor-02


IOS (tm) C2950 Software (C2950-I6Q4L2-M), Version 12.1(13)EA1

5th floor -03


IOS (tm) C2950 Software (C2950-I6Q4L2-M), Version 12.1(22)EA4

Model number: WS-C2950G-48-EI




IOS (tm) C2950 Software (C2950-I6Q4L2-M), Version 12.1(13)EA1




IOS (tm) C2950 Software (C2950-I6Q4L2-M), Version 12.1(13)EA1

Model number: WS-C2950G-48-EI

1st floor


IOS (tm) C2950 Software (C2950-I6Q4L2-M), Version 12.1(22)EA1

Model number: WS-C2950G-48-EI


Re: IP phone integration,qos

Here is a good starting point. Its vital that you get a handle on the capabilities of your edge devices first.

Re: IP phone integration,qos


a native vlan is not a must for voice traffic.

What is must is the CDP on your Switch ports enabled for Voice Vlan and the IP-phones. as IP-Phones learns the VOICE vlan through CDP protocol.

Here are some consideration when designing & implementing QoS:

1- always classify and Mark as close to the source as possible.

2- If you could do QoS on hardware better than implementing QoS in software which could impact your CPU resources.

3- always drop unwanted traffic as close to the source as possible.

Here is a good document to start with:

I am not sure if your Switches supports the needed QoS features. Please post the (show version) from one switch as they all have the same image with the same platform.



New Member

Re: IP phone integration,qos

Dear all,

Thanks for the reply. just to add my previous querries we are planning to have Avaya IP phone not cisco IP phone.

will cisco switches support Avaya IP phones?

Please find below sh ver output

Cisco Internetwork Operating System Software

IOS (tm) C2950 Software (C2950-I6Q4L2-M), Version 12.1(13)EA1, RELEASE SOFTWARE (fc1)

Copyright (c) 1986-2003 by cisco Systems, Inc.

Compiled Tue 04-Mar-03 02:14 by yenanh

Image text-base: 0x80010000, data-base: 0x805A8000

ROM: Bootstrap program is CALHOUN boot loader

Bahrain-5F-03 uptime is 1 year, 43 weeks, 4 days, 1 hour, 9 minutes

System returned to ROM by power-on

System restarted at 09:13:56 UTC Fri Oct 26 2007

System image file is "flash:/c2950-i6q4l2-mz.121-13.EA1.bin"

cisco WS-C2950G-48-EI (RC32300) processor (revision K0) with 20839K bytes of memory.

Processor board ID FOC0733Y34L

Last reset from system-reset

Running Enhanced Image

48 FastEthernet/IEEE 802.3 interface(s)

2 Gigabit Ethernet/IEEE 802.3 interface(s)

32K bytes of flash-simulated non-volatile configuration memory.

Base ethernet MAC Address: 00:0D:BD:C9:52:40

Motherboard assembly number: 73-7409-12

Power supply part number: 34-0965-01

Motherboard serial number: FOC073314Y4

Power supply serial number: DAB0732AH2P

Model revision number: K0

Motherboard revision number: A0

Model number: WS-C2950G-48-EI

System serial number: FOC0733Y34L

Configuration register is 0xF