Junaid Hattia wrote:
if a single page is faxed it works!....if multiple pages are sent, only one and a half pages of say three pages are received
Yep, well, that's generally where the other problems I alluded to crop up symptomatically. This is a complex - and, even more importantly in the case of T.38 and anything fax-related, a multi-vendor - call path. 1) Where is the fax being sent from? a) Is it a Super G3 fax machine? b) Have you ruled out the possibility of interference and/or poor PSTN service quality on the sending side? c) Does wherever you're sending from consistently work fine if you send to a conventional fax machine on your side? 2) Have you verified that the switch to T.38/UDPTL actually takes place, with a packet capture? Or does it stay G.711? It may be that the data is being exchanged using G.711u analog pass-through, which is the mode in which things stay if T.38 cannot be negotiated between all the media endpoints, and/or if fax tones are not properly detected because the sender is SG3, and/or similar situations. Analog pass-through will work, to some extent, but not over anything less than a very, very well-engineered IP network from a QoS standpoint. Even then, with all the media traversal steps involved here, I don't know that the reliability issue can be overcome for analog pass-through. T.30 is exponentially more sensitive to jitter and even the slightest bit of packet loss than voice; a little QoS issue will cause a faint (and perhaps not audible) crackle in speech, but it'll cause bits to be flipped or missing in modulated digital data. :-) And fax was built for the PSTN and synchronous transport, not at all designed to be resilient to this packetisation business. -- Alex -- Alex Balashov - Principal Evariste Systems Web : http://www.evaristesys.com/ Tel : (+1) (678) 954-0670 Direct : (+1) (678) 954-0671