this is my first post in the forum,
i want to know if Cisco 2821 router a voice gateway also? or should i have to add some module or wic? A PRI will be terminated at 2821.
Remember you also need PVDM2 that is the required DSP resources, to use router for VoIP. Do "show diag" to know if you have it and what "size" it is.
Hope this helps, please rate post if it does!