I would also like know if there is a way to monitor "location" bandwidth. We have a private fiber network running GigE between three locations. We've allocated 50 Mbps for voice calls (we're talking less than 1,000 phones here using G.711 codex). We run only about 40 Mbps of traffic even on a heavy day on any one segment and our delay is less than 1 ms (its a MAN).
Today, we got hit with an apparently "bandwidth leakage" issue (Cisco's term, not mine). The clue was when we used our IP phones to make certain calls, we got the message on the phone display "Not enough bandwidth" along with a reorder tone (fast busy).
Logging into Communications Manager (version 6.1(1)), navigating to Locations (and selecting the target locations) and clicking the Resync Bandwidth fixed the issue (at 12:25 PM during a business day!!).