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Where Are The Founders Of The Dial-Up Revolution?
RIMBoy writes "The Atlanta Journal-Constitution recently tracked down the founders behind the dial-up modem revolution. The founders of Hayes Micromodem set the standard with their AT Command set. While Dennis Hayes finds himself inducted into the Computer Industry Hall of Fame, at the same time he is broke (with a stop as a bar owner) and trying to find the next big thing. Dale Heatherington cashed out early and has dedicated himself to several projects, including ham radio."
It's been covered on slashdot many times so I'm sure people will remember, but there is a BBS Documentary in the works.
The history of such revolutions should be documented for future generations to learn from.
..Jeff Keegan
seven syllables explain TiVo: kee gan dot org slash ti vo
I worked for R&D at US Robotics for the first 56K rollout. Cots in the lab, X2 coffee (twice the grounds) as I used to call it, all week and weekend, to beat Rockwell to the punch. And we did. The first batches of course hit in mid-40's but steadily improved. Rockwell would *report* 53K or so but the actual thruput was far less. It was one of the last great times in R&D I had. Line noise is the limit. It explots the digital switching on the network. Good times.
Between the Central Offices, the connections are digital and multiplexed. The amount dedicated to each channel is 64k with 8k used for switching information. So while it's possible to run better than 56k over a phone line pair (DSL does it at least for limited distances), once you hit the CO, the 56k limit comes into play.
Lucent's 56k system could actually do 56k and stay within the limits, but the v.90 standard didn't use Lucent's technology for that.
As to why nothing is more than 56k: that is all that a standard voice line (or POTS line, for Plain Old Telephone System) can do. A POTS line is carried within a DS0 (the base channel of the phone system), and a DS0 is 64k. You can't get all 64k though, because many voice lines use "robbed bit" signalling that takes one of every eight bits to handle switch communication. Getting 56k at all requires that one end be a digital line (ISDN BRI or PRI or channelized T1); you can't push 56k through the analog to digital conversion otherwise.
The "what's next" for the telephone system is already here; it is DSL. DSL uses different frequency bands that are not used for POTS lines but that can be carried over the same copper reliably (more or less). However, DSL is not a switched circuit like a modem connection; the DSL frequencies are pulled off the line (by a DSLAM, DSL Access Multiplexer) before the line connects to the regular phone network. So, you can't "dial" a different DSL provider or your friend's house; you can only be connected to one service (and any changes require a call to the DSLAM owner, usually the phone company).
The other "what's next" was ISDN, which would give you the full 64k channel (because signalling is always done on a separate dedicated channel with ISDN), or 128k if you use both channels (the base ISDN line is a BRI, which has 2 64k data channels plus a signalling channel). However, ISDN use was slowed because it was complicated to configure (you couldn't just plug a phone in and use it), required all new equipment, and even the telcos really never understood it well (so when there was a problem, it could take weeks to get it fixed).