On Mon, Sep 25, 2006 at 08:14:27PM +0800, Steve Underwood wrote: > >Now introduce VoIP telephony... where a small amount of audio > >corruption (jitter) is anticipated on the UDP channel... and mix it > >with faxing and hopefully you can see how it just doesn't work well. > >VoIP is packetized audio passed over an IP network. Packetized audio > >is nothing new. ISDN circuits have had it for a long time now. Those > >circuits are digital - meaning the audio waveform is digitized at 8000 > >Hz... so the audio is represented with bytes and are packetized into > >frames. Those traditional digital circuits are designed to prevent > >any loss of that data. VoIP works similarly, except that the medium > >is lossy UDP/IP networking. > > ISDN doesn't packetize voice. ISDN is a strict circuit switched TDM system.
He didn't say anything about compressed, Steve; yeah, ISDN frames the bytes it sends. It sends them isochronously, certainly, so jitter is less of a problem by a couple orders of magnitude or mode, but they're still sent in "packets". Just not *IP* packets. Cheers, -- jra -- Jay R. Ashworth [EMAIL PROTECTED] Designer Baylink RFC 2100 Ashworth & Associates The Things I Think '87 e24 St Petersburg FL USA http://baylink.pitas.com +1 727 647 1274 "That's women for you; you divorce them, and 10 years later, they stop having sex with you." -- Jennifer Crusie; _Fast_Women_ _______________________________________________ --Bandwidth and Colocation provided by Easynews.com -- asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users