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Re: 28.8k transfer speed
> > Hello,
> >
> > I hardly get 3kb/sec ever, even when transferring to/from the local
> > machine (the ISP machine).
> > What could be the reason for such a difference?
>
> You should check whether the line you're using is not 1+1. Bezeq sometimes
> shares lines between two users. Since the maximum capacity of a line is
> round 33kBaud, if you split it to 2 it can limit you to 'bout 14.4 speeds.
> Note that Bezeq doesn't promise they won't change your line status (unless
> you order a special more expensive line).
>
> Yuval El-Hanany
> yuvalle@math.tau.ac.il
> yuval@checkpoint.com>
Sorry Yuval, but this is really wrong. If the line is connected to a digital
switch (and MOST are by now), then the line should hold exactly 4KHz of
bandwidth from the home to the switch. Between the switches - you need not
worry. Bezeq's infrastructure uses really high capacity lines between the
switches. So 4KHz should enable 28.8Kbps!
The only possible reason is either -
1. He is connected *through* a bad switch (somewhere between him and the ISP),
2. Or he may be directly connected to one of the few old analog switches.
About shared lines -
All digital lines are PCM coded as a standard. The standard promises you the
4KHz bandwidth. Even ADPCM compressed lines (which aren't in use in Israel
because of the relatively low demand on the lines) still allow 19.2Kbps, and
a lot of people in the USA could testify to that. I used to read the Usenet
group comp.dcom.modems around when the V.FC and V.34 standards started. Most
have managed 21000bps (V.FC) and some 24000, 26400 etc.
What I said by "the relatively low demand on the lines":
I mean that in Israel, the load on the lines between the switches never get
high enough (as they do in the USA) to necessitate ADPCM or better compression
methods.
The only "More Expensive" lines that you can order are ISDN lines, but almost
nobody has them yet, nor does anyone have the expensive modems to use them.
Hope this clarifies a few things.
Amit.