Author: Vic Date: To: hampshire Subject: Re: [Hampshire] Request for email users...
> The other caveat > with SIP is that you need 1Mb connection speed minimum for decent call
> quality.
Errr - no.
Running PCM[1] over RTP (which is what eats the bandwidth) takes about
80Kb/s in each direction (it's the upstream that gets you on ADSL).
If you run GSM or some such, it's half that. My favourite codec
quality-wise is ILBC (which sounds just lovely) - but that is extremely
CPU-intensive.
And if you really want to squeeze the bandwidth, use G.723. 5.3Kbps![2].
But what you need in any event is a low-latency connection; I've a nasty
feeling that certain telcos are going to be having mysterious problems
with certain packet types as their revenues from calls drop off...
Vic.
[1] G.711 really - but it might as well be PCM :-)
[2] But it sounds *awful*. The 6.3Kbps is markedly better - but still
near-unintelligible.