Hi Arnaldo, That's interesting - Brasil was my first proper IVR installation: one with Embratel in Sao Paulo, and then a couple with TeleRJ. I remember landing at Sao Paulo airport for the first time at 7 a.m. with instructions to "meet a fat man called Ferrari" unsure as to whether I was in some sort of elaborate hoax (I wasn't, and he was), and learning my first three words of Portuguese as we left the car park: filho da puta, of course.
Those had no EC. DTMF detection worked fine, and the audio quality of the IVR recordings was perfect, which is what you'd expect: EC doesn't alter the IVR->caller audio at all. A TDM->SIP->TDM type application is a different animal: you've got the added latency of packetisation/jitter buffering/etc. which pretty much makes echo cancellation a must. --Dave > Sharing my humble experience: in Brazil we usually need echo > cancellation to have reliable DTMF detection _and_ voice quality over > E1 lines (be it on MFC/R2 - r2d - or ISDN PRI lines), either for > sip/tdm gateway devices or IVR applications. > > Usually there's no need for echo cancellation on links from some > Telcos, in some specific places. But we need it in the majority of > cases, even when my box is just a gateway between legacy pbxes. > > This represents just a subset of the available E1s in the world and > it's just a practical experience, but it's a fact for me. If I don't > have a card with echo cancellation, I don't offer reliability to my > customer; I've done that in the past and didn't work out. > > I'm not theoretically discussing anything, just sharing what I've been > through in the last 4 or 5 years. _______________________________________________ Freeswitch-users mailing list [email protected] http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org
