CAC

The_guroo_2 · ‎02-04-2009

Guys i am a newbee to VOIP....just wanted to ask that CAC is used to limit the bandwidth on WAN links if it get oversubscribed......why we use gatekeeper then??? do it do the same thingor its different.....thanks guys

gogasca · ‎02-04-2009

GK is also used for CAC

We have in CUCM Locations CAC.

Please take a look at CUCM SRND guide and our Cisco docs for GK CAC and Locations CAC.

webstd.design · ‎02-05-2009

Also notice, that there is a feature called AAR?

Jonathan Schulenberg · ‎02-05-2009

UC Manager CAC and Gatekeeper CAC are used in different deployment scenarios.

UC Manager CAC (Locations-based or RSVP-based) is used for phones controlled by a UCM cluster. Gatekeeper CAC is typically used for calls between different UCM clusters.

AAR stands for Automatic Alternative Routing. When AAR is configured and an on-net call (between two IP phones on the same cluster) is denied because of CAC, UCM will reroute the call across the PSTN. The general idea is when Bob calls Joe's extension and there is no WAN bandwidth, AAR will call Joe over the PSTN automatically. AAR does *not* occur if Joe's phone is unregistered because the WAN is down.