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QOS for VOIP over frame realy slows down when used with a AIM-COMPR2 card

I'm using 2600 routers connected via a frame relay pvc with a 768k port and CIR transporting VoIP (from DVM's on each router). Each router also has a AIM-COMPR2 card. When I apply standard traffic shaping map classes, the customer complains their application response deteriorates to the point of being useless. I've configured the parameters for no Be and a Tc factor of 10ms, along with IP RTP header conmpression. Do I need to enable CEF, ditributed queueing, or something else to get the traffic shaping to work? I just need to prioritize the voice- any method that will accomplish that without wasting unused bandwidth will work.


Re: QOS for VOIP over frame realy slows down when used with a AI

AIM compression module of course would add

another x ms delay to the delay which would be

already induced to data traffic when you prioritise voice.

Voice RTP stream should not be compressed at all, hence we introduce too

much delay and corruption doing decompresion.

For traffic-shaping & prioritization

you can use the map-class below.

map-class fram-relay VOIP

frame-relay CIR 768000

frame-relay bc 768

frame-relay be 0

frame-relay fair-queue

frame-relay ip rtp priority 16384 16383

frame-relay fragement 640

no frame-relay adptive-shaping

X in the fram-relay map above mean the the amount of bandwidht you'll

like to reserve for voice traffic and can be from 0 to 75% of total bandwidht.

If there is no voice flowing, the X is used by data , so bandwidth is not tied down.

My concern is make sure voice traffic is not compressed.

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