My company is in the planning phase of relocating one of our departments from our HQ building (10.1.x.x) to one of our other existing sites (10.5.x.x). The one thing of key importance to the project is that the phone extensions of the department stay the same as they presently are. I was told that in order to do this, I need to setup a subnet on the 10.1.x.x within the 10.5.x.x site. Both sites have not been subnetted but just run with the 10.x.x.x 255.255.0.0 mask.
The network breakdown is as follows. We are using a 3com NBX at both sites, which each have different extension groups. We have Cisco routers at both sites, connected via T1.
My question is how do I make the 10.1.x.x subnet work at the 10.5.x.x site? Do I need a dedicated port on each router to accomplish this or could I just specify the subnet via a route command in one or both routers?
