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New Member

Fax over IP with 1750 voice module

Hi all,

For two fax machine(at two differenet sites) each terminated by 1750 router(with voice module) across an IP network, suppose with more than enough bandwidth and free of packet loss/poor latency; what could cause a consistent distorted fax output(always partially compressed)? Any workarounds I can try??

Thanks in advanace,


New Member

Re: Fax over IP with 1750 voice module

Are you trying fax-relay or not?

If no fax-relay, be sure to set the codec that fax is using to g711ulaw, any higher compression will likely distort fax tones.

If yes, fax-relay, then make sure that the call is indeed using fax-relay on both sides, and negotiating it correctly by doing "show voice dsp" and show voice call summ.

Then look at the statistics of the call .

term mon

show voice call sum (pick up the channel, say 1/1/1 and do)

show voice call 1/1/1

this will show any errors on the DSPs , any jitter indications, or any other problems, basically be sure that the counters are very small values and are not incrementing.

Hope this helps.

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