2009/12/29 VinÃcius Fontes <[email protected]>: > Hello everyone. > > I'm trying to set up a SIP DID on a customer, which uses T.38 for faxing. > Voice is working great, but I never configured anything using T.38 in > Asterisk so I'm kinda lost.
So you're trying to use a SPA8000 to act as a gateway, then you're trying to put asterisk somewhere. And there's a real fax machine involved. I don't think you've given enough information for anybody to actually tell you what went wrong with your 'transmission error'. So here are my suggestions: * if you're not already using the latest 1.6, you should be. A lot of T.38 and faxing-in-general improvements have been released. * are you sure the T.38 is actually negotiating? * if you leave T.38 disabled, everything should try to pass traditional audio over the VoIP codec of your choosing, and if you have a fairly reliable network, you MAY be able to accomplish faxing in that manner. * And now for my personal opinion... if you need reliable faxing, you shouldn't be using a SIP trunk into the premise, but rather a real traditional phone line. Fax is a hack to play tones to represent an image. VoIP is a hack to try to reduce the quality of a voice call without a human noticing. Put those together over the internet, and you shouldn't expect reliable faxing. Fax machines are much less forgiving than a human. If you lose data in the middle of a fax, the fax machine gets confused and can drop a fax that was mostly received okay. * I do think fax over voip has good usages. That means if you have a dedicated line to your voip provider with reliable quality, you would probably be okay. If you have a dedicated LAN that you are using internally for voip fax you are also probably okay. * if this whole project is an effort to save money and avoid the Brazil telco monopoly, you should consider paying for one of those services that allows you to send and receive faxes using a third-party, and not try to receive faxes at the premise. _______________________________________________ -- Bandwidth and Colocation Provided by http://www.api-digital.com -- asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
