I'm installing a Norstar BCM 400 with all IP phones. 20 IP phones will be at the main site. 6 of the IP phones will be at a remote site 500 ft away. The network between the buildings is connected by a cat5e cable.I am going to upgrade the main site switch to QOS, and will install either a hub or another QOS switch, if necessary, at remote site. Is it necessary to buy a QOS switch for the remote site as well, or will a hub suffice?

Is 500 ft too far away for the 6 remote IP phones to work off the main QOS switch? Do I need a data extender of some kind?

500 feet is over what it is rated at. I am surprised you are not using fiber.

The cat5e was already in place. The cost of installing fiber is cost prohibitive.

An IP phone is a data appliance. Sames rules apply -100m.

how far is it between the buildings? You can put a small switch in at the exit point of the cable, hopefully getting the distance under 100m, or 323'

jjimm, you can put a pair of RAD ASM-61 units in to extend the ethernet. It will only give you 10mbps. It only uses 1 pair. Make sure you put surge protection on both the power and cable pair. They are simple to install and work well for low cost.

Using the RAD ASM-61 unit, how would you determine which of the (4) cat5 data pairs to use for extending the network?

You could also use a TUT MDU Lite on one end. Then use a TUT "Modem" on the other side. Once again it will only push 10mbps. However I belive the TUT equipment is about 1/2 the cost of RAD.

Also the pair that carries the signal is whatever pair you wire it to. Which is typically the blue pair, as you can use 6p4c (RJ11) connectors for DSL/PNA.