I would think you could use CAC based on the location field which should take into account the bandwidth.
Location
Use locations to implement call admission control (CAC) in a centralized call-processing system. CAC enables you to regulate audio quality and video availability by limiting the amount of bandwidth that is available for audio and video calls over links between locations. The location specifies the total bandwidth that is available for calls to and from this location.
From the drop-down list box, choose the appropriate location for this conference bridge.
A location setting of Hub_None means that the locations feature does not keep track of the bandwidth that this conference bridge consumes. A location setting of Phantom specifies a location that enables successful CAC across intercluster trunks that use H.323 protocol or SIP.
To configure a new location, use the System > Location menu option.
For more details about locations, see the Location Configuration topic. For an explanation of location-based CAC across intercluster trunks, see Location-Based Call Admission Control Over Intercluster Trunk in the Cisco Unified Communications Manager System Guide.
TONY
