Networks

Does anyone have a "best practice" document that you have developed for changing an active subnet to another subnet? We have a division that we need to move IP address ranges to another range. The old address range needs to remain in effect for a period of time for some critical services. We don't want the traffic to hit our frame relay router to resolve the best path between networks since they are both on the same local LAN. Other sites come into the frame relay router to get to services on both networks.

Thanks for your support on this.