[wellylug] VOIP calling band-width usage

[Richard Wade]

On Fri, August 17, 2007 15:41, Richard Wade wrote:

> The numbers I'm using are roughly 50kb/s for the VoIP, considering that
> Skype uses G.729 and that it's a nice round number. For video, I think I
> measured by gateway doing about 120-150kb/s (from vague memory), so
> roughly three times the VoIP-only bandwidth. I'm considering that the
> bandwidth usage is counted in both the upstream and downstream directions.

Replying to my own message here, but noticed that I've made the assumption
of G.729 codec (hence around 50kb/s-ish in each direction). This is
certainly the codec I've seen used for Skype to PSTN calls. I believe
Skype uses a proprietary licensed codec for Skype to Skype calls, which
probably uses much less bandwidth. I've not taken these measurements, but
I'm sure a quick Web search will reveal further information. The upshot of
this is that if you're talking Skype to Skype (as opposed to using
SkypeOut to call the PSTN), then you'll get many more call minutes to your
GB of cap usage.
-- 
rik