Ryan McGuire wrote:
Unless your network is under load and you are seeing dropped packets and high jitter, I would absolutely not do T.38. The cheapest and easiest approach that I have found is to buy yourself an FXS gateway and just make sure you are using ulaw.
As SIP is usually running over UDP/IP it doesn't take much to produce dropped packets. Dropped packets mean lost audio which means lost data and possible demodulation difficulties for the modems. If you're in an environment where dropped UDP packets don't occur you're in a very rare scenario.
For the most part people who claim success when faxing over SIP G.711 are being rescued by ECM (error correction) within the fax protocol. There are very, very few who really have mitigated UDP packet loss.
That said, all T.38 systems are not equal. Certainly, the reliability of your T.38 provider may not be any better than that of G.711 fax over the SIP UDP.
I only recommend faxing over TDM everything else is at your own risk. Thanks, Lee. -- _____________________________________________________________________ -- Bandwidth and Colocation Provided by http://www.api-digital.com -- New to Asterisk? Join us for a live introductory webinar every Thurs: http://www.asterisk.org/hello asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
