The first thing I would do is see what software options are available for your equipment. Sometimes enabling QoS is a matter of a software upgrade. If that is not possible, then check with Polycom and see if it is necessary. Sometimes the software utilizes streaming and multicast which eliminates the need for rolling QoS out to every laptop. The other option you have, obviously, is IP nailing and to enable QoS based on IP address if it is possible. You can do about the same with DHCP long term leases based on MAC address. If you have to do QoS via switch port and have no higher capabilities, then it gets tricky. You certainly don’t want to “trust” all, but you might be able to trust all and then remove that trust in your firewall. There really are a lot of options, but I think your safest and cheapest bet is to determine if you really need QoS on the desktops. Think of it this way, if you use Skype, or other messenger services with video, QoS isn’t needed as the software handles compression, etc. You may be OK the way you are. And finally, you may be able to share the Polycom resources via the network and have users attach through those resources for the conferencing.