We currently have 3 sites using Alcatel OmniPCX PBX`s (SIP trunks between sites currently) + 1 sites using an legacy PBX all connected via WAN (All Cisco routers) from a central data center (2921 ISR w/ SECK9).
What we are looking at doing is centralize the ISDN and PSTN trunks at each site to a single 20 channel (possibly 30) IP SIP trunk delivered to the data center.
What we would need to do is terminate the 20 or 30 channel SIP trunk in the DC then depending on the Dialed number passed through the trunk the router would then forward to the configured SIP trunk being the Alcatels at each site depending on routing rules for numbers.
Would I correct in saying that we would need to purchase the Cisco Unified Border Element and an UC license for the 2921 to support this and perform these operations ? Then the CUBE would handle the routing of calls based on passed through parameters from the Voice Carrier by SIP ?
Also would the UC license allow us to utilize CME or is there an additional license for this as possible we would deploy CME w/ Cisco IP Phones at the 4th Site (Legal PBX) utilizing the DC router for the host of the CME.
Thanks for your assistance in advanced quite confused with the new Cisco Licensing structure ( IOS 15 )