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New Member

Intermittent problems in VoIP over Frame Relay

WE have a WAN connection using PBX - PBX connection(384k CIR 320k Be 704k max bandwidth).

. After conversations have been going for some time we get crackling and single or multiple word drops. Otherwise the voice is great quality.

The carrier has suggested serialization delay even though I have priority queues configured and I understand why they suggest this but interestingly the problem is worse at low loads on the link.

I have tried frame relay fragmentation but the voice call drops out after about 10 seconds. I will be pursuing

Anyone have a similar experience and any advice on how to resolve this issue..

New Member

Re: Intermittent problems in VoIP over Frame Relay

I will suggest monitoring delay over the ISP's network (<=150ms). I am thinking maybe the ISP's network (or your circuit) is not geared to hadle time-sensitive traffic. if they are not setup to handle you level of QOS, any fency design on both ends of you circuit will add verly little to the quality of the traffic. if you do solve the problem eventually, i will be interested in knowing what the real issue was.


New Member

Re: Intermittent problems in VoIP over Frame Relay

Check the processor utilization. If the processor is being taxed, it will drop or delay packets, even though your configuration is otherwise perfect.

As I understand it, Frame relay fragmentation and low latency queuing is the preferred qos solution in your case.

Hope this helps;


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