-----BEGIN PGP SIGNED MESSAGE----- Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit To: erp@digiforest.com, cypherpunks@toad.com Date: Tue Sep 17 08:20:07 1996 Argh, criticism!!!!! :-0

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3. NO transmission over a standard phoneline can have more than 3100 baud, because the frequency of anything transmitted over that line is band limited to 300hz - 3400hz. (If you have ISDN it's not relevant anyway, since you are fixed with 8000hz or 64000 bps->in europe :), 56000 bps in usa)

Personally, by saying that no transmission on a standard phoneline can have more than 3100 baud, is a statement saying that technology and science, shall never advance, to a point where things are possible. If you remember right, just 10 or so years ago, we stated that 2400 baud was the highest possible baud, and we would never go over. My modem, running on a standard phone line, is a 28.8 USRobotics modem, with the software, and hardware upgrades to a 3400 baud, I get on an average day anywhere from 3500 to 3600 baud for send/receive. On a bad day, I only get 3100 to 3200. SO I would say, that my phone lines, are cleaner than most eh? And Yes, I am in the US. Speaking of ISDN, how many people, can afford to have a personal ISDN line in there house? And then afford to connect to something/someone else on a next to permanent basis monthly?

Well, if your modems says to "hell with the switch", you can do a lot of things with frequencies. And since the filters in the switch are not that accurate, you *might* get away with 3400 hz, which I doubt. Now if your phonecompany for what reason ever supports more bandwidth, thats good for you, but try to get your 3600 baud = 3600 hz modem to be accepted by the FCC will pose a problem, since it states in the regulations, that a modem has to stick to the 300-3400 hz band limits.

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4. Most modern transmission schemes work with multiple bits per baud. I.e. you transmit 10 bits in one baud if you have a 31000 bps modem. the only limitation in transmission speed is the amount of binary values you can pack into one baud. that on the other hand is limited by the S/N (signal to noise) ratio of your line. If you have a noise of 0.9%, you can't use more than 100 steps or you have ambiguous signals. since people talk about 56000 bps modems (we tried 34000 modems here and they couldn't produce more than 28800 on a very good connection) that would mean, that you have to transmit 18 bits = 262144 (!) distinguishable signal forms per baud.

What about new ways of splitting the steps and baud more so that it shows less at a higher level.... Just a question.. Ahh well, I'm getting a page so I shall finish this now... Answer appreciated..

Huh? - ------< fate favors the prepared mind >------ Remo Pini rp@rpini.com PGP: http://www.rpini.com/crypto/crypto.html - ----< words are what reality is made of >---- -----BEGIN PGP SIGNATURE----- Version: 2.6.3i Charset: noconv iQEVAwUBMj5DGBFhy5sz+bTpAQFQtwf/diE965nL6MCKX4ikXDyda9hq4a4yGQmV dxYHxD7ADCu32j+InC0FSCevO9Cjn5SoUhrHxsXHj/ZVaBEXRtJLX9g771FciBAz dqq1kKVVoFOJZGUCLUoHSD56tAU2t8pwXHu0QdnJWSpTLj9BausXGGcLH8PEJlAG 5bi3WP4M95Np/8nXUbR/GHlHiVLULRzDCgRLgVfDYe5NHgft69wXB5S3PoD/QUul ranoj1+4xk92M9SarPzcG8/gboR1EFVxgRdgLIi0zeyO+D0Ler648Btf6BgMdaSd Cr+9mzn/KXmrxHS4t6IPt+ZmZiUhzZHCcuxKrkb1JDz7pP6czhytyA== =0WaE -----END PGP SIGNATURE-----