[plug] What you give shall you receive....

[Peter Wright]

On Fri, Oct 22, 1999 at 06:20:03AM +0800, Garth Atkinson wrote:
> Hello Pluggers
> 
> Bruised and bloody by some modem wars

Ow.

> I seek assistance.
>
> I have configured a simple PPP link between two 56K modems. In one
> direction I can achieve the wonderful throughput figure of 5.6
> Kbytes per second (measured by ftp'ing a 1 Meg file). In the other
> direction I get exactly half that figure (2.8 Kbytes per second,
> measured by ftp'ing a 1 Meg file). Both modems are external Hayes
> Accura 56K+.
> 
> Whats going on?

This may or may not be of any help to you, but...

I do remember reading when 56K modems were first coming out, that
apparently the 56K speed could only be attained in _one_ direction
(ie. from the usual person-dialing-ISP perspective, the person gets
56K downloads, but only 33K (approx) uploads.

It's something to do with the maximum normal transfer rate possible on
ordinary phone lines being very close to 33K, ie. that provided by a
normal 33.6K modem. 56K modems do some sort of funky trick that
significantly enhances the transfer rate in one direction, but does
bugger all for the other direction (in fact it might even lower it).

> Garth

If you weren't aware of the above, try hunting for an FAQ/howto/etc.
relating to 56K modems and you might get some actually useful
information from someone who knows what they're talking about. :)

Pete.
-- 
http://cygnus.uwa.edu.au/~pete/

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