[cisco-voip] Deploying RSVP in a CM 4.1.3 environment to supplement locations-based CAC

[Robert Kulagowski]

I'm reading Cisco Voice GW and GK.

Most of my remote sites have a single WAN connection.  Those sites have 
a location CAC of 270k in CM (which is what our provider will guarantee 
in their real-time voice queue for QOS).  Remote sites all use H.323.

Only VM traffic goes over the WAN back to Unity; all other calls go over 
PSTN.

If the WAN is out, then the site goes into SRST.  Users hate that.

At some sites we're deploying a second router through a different 
provider.  No QOS on that link.  ACLs block voice traffic, because if I 
allow phones to register over this link, then they'll think that they 
can talk to Unity, and we don't want that.

I'm thinking that if I can setup RSVP, I can set the interfaces so that 
the primary router has a rsvp bandwidth equal to the RTVo queue.  And 
that the secondary router will have a RSVP bandwidth of 0, but will 
allow SCCP traffic to traverse.  Phones will stay registered.

1)  Is this feasible?
2)  Is it practical?
2a)  Is it solving my problem?
3)  I don't have to deploy gatekeepers, do I?
3a)  Locations sound an awful lot like zones - why can't my Polycom 
H.323 video unit register to CM 4.1.3?  (why isn't CM a H.323 gatekeeper?)
4)  Will I set my locations bandwidth to Infinity and let the VGW decide 
  what to do?
5)  Am I going to use AAR at all on CM?  Would I use a route pattern to 
intercept the pilot number of Unity so that users that press "Messages" 
get their call sent to the gateway instead of setting up a WAN/IP call?