OS Image distribution subnet in a WAN

What are the fundamentals to establishing a traffic isolating subnet in a large routed WAN using Cisco switches and routers? The subnet should handle only image distribution requests from clients connected to the WAN that have a need for OS re-imaging. For example WAN is 192.168.x.x and Imaging subnet is 192.168.254.x which hosts the an imaging/ghosting server that supports clients on the 192.168.x.x WAN.

This will be helpful for majority of large networks out there using chatty protocols that can become a performance choke point even with ever growing bandwidth addition.