Voice Solution, Layer 3 needed or can i get away with a Layer 2 Switch

[TheBR]

Hi,
We are currently using a solution to provide voice and data connectivity to PC's and non Cisco IP phones using Cisco 3750 Switches at the edge with IP routing on and connected back to distribution layer 6500's which are also layer 3.

The configuration of the interfaces on the 3750's are as follows:-

interface GigabitEthernet1/0/X
description +++End-User Ports+++
switchport access vlan 1
switchport mode access
switchport voice vlan 2
srr-queue bandwidth share 1 70 25 5
priority-queue out
mls qos trust cos
spanning-tree portfast
spanning-tree bpduguard enable

The phones themselves are tagging packets and giving the Voice traffic DSCP value 46.

We currently have an Ip Access list in place preventing communication between the two VLANS.

Im wondering, if we used a Layer 2 Cisco 2960 with PoE instead of the more expensive Layer 3 3750 if the same solution would work, given that the two Vlans shoudlnt talk to each other AND that the 6500 can do routing anyway.

Or are the Layer 3 capabilities needed for the "trunk", i.e. the two VLans on the one interface?

Thanks.

 

[vipergg]

Yes if you are going to trust the incoming cos then you can use a 2960 without a problem . Most of the qos commands are the same for the 2960 and 3750 . If you are going to get into remarking packets then I think you need a layer 3 device.

 

[TheBR]

Remarking packets is not a problem, the are simply trusted. I just wasn't sure if this specifically:-

switchport access vlan 1
switchport mode access
switchport voice vlan 2

Would have required a layer 3 device as you have 2 Vlans on the one interface.

 

[baddos]

You don't need a layer3 switch to use "voice vlan" configuration.