Setting up QOS

[carl_townshend]

hi all, when setting up qos in my network, I set up untrusted ports for my phones, then apply qos to it, between switches I gather I create a trusted port, my question is, on the trusted port, will it honour any tags that come through, ie vlan 128 has 0x2e, and vlan 100 has 0x22 ?

[Collin Clark]

Best practices is to set the trust point as close to the phone as possible. If you're all Cisco, you can trust the phone (and probably should). As far as honoring, let's look at a data example, that might help clear it up a bit. Let's say you want to trust the phone, but not the PC. You can configure the switch to trust the phone markings, but reset all the data marking to 0. Imagine a user that figured out how to set the QoS markings in WindowsXP to EF! Does that make sense? As far as trunks, you don't need to trust the ports, but it doesn't hurt (AFAIK) to have it on.