Fax over IP with 1750 voice module

[goku-sun]

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,

Goku

[fbahram]

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.