Bits & Bytes
MODEMS: ON THE VERGE OF MAXING OUT
Modems are about to hit the speed limit. The rate at which modems transmit data over ordinary phone lines has already jumped fifty-fold since the 1960s, when they could send only 300 bits of data per second. The latest models, V.32bis, can send 14,400 bits of data per second. Now, manufacturers are negotiating a new international standard--temporarily dubbed "V.fast"--for modems that will run at up to 24,000 bits per second. That speed, engineers say, approaches the physical limitations of today's phone lines.
V.fast modems will eke out more speed with new chips that improve signal coding and by using the ragged edges of communications channels that have been off-limits to earlier modems, says Richard P. Brandt, owner of dB Consulting in Annandale, N. J. Brandt is also chairman of the International Telegraph & Telephone Consultative Committee working party that oversees modem standards. However, the standards effort has hit its own speed limit: Wrangling between manufacturers will delay introduction of the new modems until 1993. For some speed-hungry customers, that's V.slow.EDITED BY SUNITA WADEKAR-BHARGAVA