Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. If you'd prefer to explore, try our test area to get started. And see here for current known issues.

New Member

problem with VoIP bandwidth reservation

I have the following scenario:



2 FXO>ROUTER_A ------ F. R. CLOUD -----ROUTER_C<2 FXO ports


The WAN provider gives me 2 PVC's: ROUTER_B <-> ROUTER_A


So ROUTER_A is at two hops from ROUTER_C. <br>

Voice calls between A and C works fine as long as the data traffic

doesn't reach a certain level, in wich voice quality quickly degrades.<br>

Previously I've used RSVP to acomplish QoS but always the routers

where directly connected or at least in the same F.R. PVC, etc.

The same configuration here doesn't work.<br>

My doubt is: is possible for this to work at all? If so, wich QoS

method should I use?

Any sample configuration?

Thanks in advance for any hint or suggestion


New Member

Re: problem with VoIP bandwidth reservation

For RSVP to work, which is still not the preferred method, you must configure it on every single router in the path of the voip call.

The best way to configure traffic shaping, prioritization and fragmentation for your 3 routers, to process voip calls and give it priority over all data and also avoid delay by fragmenting your large data packets , is to use frame-relay traffic shaping and ip rtp priority OR LLQ. Either IP RTP PRIORITY or LLQ will do the prioritization for you....

A sample config is shown below:

Hope this helps.