We have a customer with a voip network. There is a central router (cisco3620) connected with a PBX and 100 remote sites with a cisco827-4v or cisco 1760-v with two analog phones connected.
At this point we need to introduce a gatekeeper to help us to manage the numbering plan.
A year ago we planned to use two cisco2621 (redundant configuration) fot this purpose. The IOS we needed for this case was IP/H323. But now we prefer to use a cisco2801, what IOS we need? Are we going to have compatibility problems with older routers like cisco827?