I want to allow extension mobility.
i have a Cisco 2811 router with a cme 3.3.
I just saw from :
Im not sure but it seems my cme is not compatible. is it possible to upgrade ? or what's my other options?
thanks in advance.
Yes, you need to upgrade. For this, you need to purchase (if you haven't already) a support contract for your router, available at any official cisco reseller. You will register under your CCO profile and will be allowed to download software.
The one you want is IOS 12.4(11)XW5.
Hope this helps, please rate post if it does!