When you have a site with two gateways(routers) into the MPLS WAN, and you configure QOS for RTP, and on the GK you configure your zone to handle a bandwidth of say 4MB. On one of your gateways its links are 5MB, but on the second gateway link it is only 2MB. Let?s say the first link fails and all your calls are going over the 2MB connection. Gatekeeper?s configured CAC is 4mb for the zone, won?t calls now fail and not go over to PSTN with AAR because the CAC only knows how many calls are tacked up so it won?t see the 4mb total because the site link is 2mb. How do you configure around this? Are you at the mercy of the 2mb limit then with your CAC?
Would RSVP be a better solution in a large WAN with multiple clusters and sites?