[ILUG] [OT] Genesis Europe, dirt cheap Internet access..

[John Allen]

Jeremy Smyth wrote:

> > > Yes, but IIRC a V.90 connection is still at 9600 baud,
> > regardless of how
> > > many bps you're getting - the baud rate stays the same.
> >
> > If baud is a measure of the number of signal changes per second,
> > how is it possible to send a bit without changing the signal,
> > whether FM, or AM?
> >
>
> Compression. You've heard of V32, V32FC, V32bis, V34, V34+, V90, etc.
> They're all different ways of squishing up to 56kbits into a bandwidth that
> can only realistically support 8KHz, i.e. 8K signal changes per second. Baud
> is physical signal changes, bps is what you have after decompression.
>
> Like you can store 20MB of files in a .tgz that's only 8MB. You haven't lost
> any information, it's just compressed.
>

I see clearly now

But I still don't understand why my home phone line is dead reliable at 33k
but quite flaky at 56k. If it were only compression that was producing the
increased bandwidth, then surely the reliability should be consistent?

>
> /jer
>
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