We have an existing 3845 router that we were planning on using for a voice gateway with traditional T1s. It has the voice IOS feature set and enough DSPs.
Our provider (AT&T) is proposing a 10MB SIP connection instead of traditional T1s. But they've also indicated I'll need a CUBE license.
I read about CUBE at http://www.cisco.com/en/US/prod/collateral/voicesw/ps6790/gatecont/ps5640/product_data_sheet09186a00801da698.html but I wasn't sure if it's required or just recommended -- and what features it gives me. It seems like it's an added hidden expense of SIP vs traditional T1s.
Also are the DSPs still needed if my incoming connection is SIP? I imagine it is to translate between codecs?