Miguel Ruiz Velasco Sobrino
2005-Jan-18 13:27 UTC
[Asterisk-Users] Re: Asterisk bandwidth tuning?
I have an installation that connects in a [very] good day at 22kbps, but the normal is about 18kbps. I use de ILBC codec, and also change in iax.conf the trunkfreq = 20 to trunkfreq = 30 It works, you can understand well the other person, but don't expect miracles or an outstanding sound quality.> Dear Dan; > > Thanks alot for your kindly reply. > > Well, what u advise us to use if the bandwidth is about 22kbps (dial up > connection in very old countries)? >> >> GSM Codec is 13k plus overhead. That may work?>No way. GSM is 13.2kbps, and with Asterisk's hardcoded 20ms >packetization, this gives 29200bps with RTP-based protocols or 26000bps >with IAX, and as long as Asterisk doesn't support silence suppression, >this needs to be full duplex, and I doubt you don't get that from a >modem. If we could add silence suppression, we could do with half >duplex, effectively saving half the bandwidth. in addition, if we could >increase the packetization to something like 50 or 100ms for extreme >use (like dial-up), we could end up with a lot less. Say, using 100ms >slicing with IAX and speex at 6.3kbps, we'll end up with effective >bandwidth use of 8860bps plus ethernet. now that's something you can >brag about....>royMiguel Ruiz Velasco __________________________________ Do you Yahoo!? Yahoo! Mail - 250MB free storage. Do more. Manage less. http://info.mail.yahoo.com/mail_250
alexandre::aldeia digital
2005-Jan-19 10:05 UTC
[Asterisk-Users] Re: Asterisk bandwidth tuning?
18 - 22 Kbps .... my dream! I have asterisk -> INTERNET -> asterisk connection with IAX2 and I try iLBC, gsm, g729 and speex and the minimun bandwidth was 38 Kbps for 1 channel. What the parameters do you set to have this rate ??? Thank you. Miguel Ruiz Velasco Sobrino wrote:> I have an installation that connects in a [very] good day at 22kbps, but the normal is > about 18kbps. > I use de ILBC codec, and also change in iax.conf the > trunkfreq = 20 > to > trunkfreq = 30 > > It works, you can understand well the other person, but don't expect miracles or an > outstanding sound quality. > > > >>Dear Dan; >> >>Thanks alot for your kindly reply. >> >>Well, what u advise us to use if the bandwidth is about 22kbps (dial up >>connection in very old countries)? >> >>>GSM Codec is 13k plus overhead. That may work? > > >>No way. GSM is 13.2kbps, and with Asterisk's hardcoded 20ms >>packetization, this gives 29200bps with RTP-based protocols or 26000bps >>with IAX, and as long as Asterisk doesn't support silence suppression, >>this needs to be full duplex, and I doubt you don't get that from a >>modem. If we could add silence suppression, we could do with half >>duplex, effectively saving half the bandwidth. in addition, if we could >>increase the packetization to something like 50 or 100ms for extreme >>use (like dial-up), we could end up with a lot less. Say, using 100ms >>slicing with IAX and speex at 6.3kbps, we'll end up with effective >>bandwidth use of 8860bps plus ethernet. now that's something you can >>brag about.... > > >>roy > > > Miguel Ruiz Velasco > > > > __________________________________ > Do you Yahoo!? > Yahoo! Mail - 250MB free storage. Do more. Manage less. > http://info.mail.yahoo.com/mail_250 > _______________________________________________ > Asterisk-Users mailing list > Asterisk-Users@lists.digium.com > http://lists.digium.com/mailman/listinfo/asterisk-users > To UNSUBSCRIBE or update options visit: > http://lists.digium.com/mailman/listinfo/asterisk-users