> On Wednesday, January 28, 1998 12:04 PM, Christer Olsson
> [SMTP:cox@clavicula.mednet.gu.se] wrote:
> > Mostly, they begin with 50K, but drops to 44K (good line) or 34K
> > (bad line). Other modems usually gives 44-48K and I?ve never seen any
> > reliable 50K connection here. So I wonder why the modems thinks 50K is
> > possibly and renegotiates directly after the connection?
>
> This happens for the same reason that 33.6 modems tend to connect at 28.8
> initially but then renegotiate up to 31.2 or higher immediately after
> connecting.
>
> You have to remember that the modem isn't sending any data while it's
> handshaking. It's simply probing the line and making some educated guesses
> about the quality of the circuit it's on. Once it gets a carrier, it *is*
> sending data, and it can see how reliably the data is getting to the other
> side. At a certain point, the retransmit delay because of bad data
> surpasses the speed increase gained by being at the higher rate. At this
> point, the modem (and rightfully so) drops to a lower rate to avoid as many
> errors as possible.
I did some tests with the E-tech Bullet modem and it connects into 50K.
When trying to get data, it drops to 48K and then to 46K. With 46K it
works really stable, but if I pause a few seconds, the modem tries to
retrain to 50K again! And when the data begins, the modem drops again..
That gives terrible performance..
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