Pretty straight-forward question here, I think:
We have a customer that currently has Cisco ISR routers (2821s, specifically) serving as voice gateways for PRI circuits at multiple sites. This customer is converting their voice connectivity to SIP trunks, which were all turned up this past week w/ an Ethernet handoff. They want to test out the SIP trunking before they officially cut everything over from the PSTN voice circuits. So...
We need to know if it's possible to have an ISR router operate as the current voice gateway AND Cisco Unified Border Element (CUBE) for the SIP trunk endpoint simultaneously. This way, they could test the SIP trunking operation w/o any downtime and w/o buying extra ISRs to operate as separate CUBEs. I don't see why this wouldn't be allowed, but someone indicated today that this MAY not be supported by Cisco (that the CUBE must be a standalone router dedicated to this role).
Looking for input or confirmation either way, and thanks!