Location-based call admission control is used in Cisco UCM to control the amount of bandwidth...

A limit of 900 kb is the total amount of bandwidth used for the sum of calls. The use of compression does not impact the amount of calls because only the codec definition is considered when calculating the CAC in Cisco UCM

A limit of 900 kb is the total amount of actual used RTP traffic so the oversubscription can be done for multiple calls adding its maximum RTP stream requirements.

A limit of 900 kb is the total amount of bandwidth used for the sum of the media and signaling in the calls The system allows for an actual of 20% overhead of IP packet headers This is to compare the use of ISDN lines with no IP overhead.

A limit of 900 kb is the total amount of bandwidth used for the sum of calls of the defined codec including headers and media traffic