Casting a Faster Net
“Always on” service redies for home markets
Sometimes it seems as though the Internet had been invented to foster manic depression. There’s the glee of finding information in a few seconds. Then, the head-banging frustration of waiting as an image fills the screen pixel by excruciating pixel. Most home Net users, in particular, sip data through modems operating at 28.8 kilobits per second. The newest modems offer 56 kilobits per second-not an overwhelming boost.
But home Internet users may soon have available to them the Net equivalent of lithium. Starting this year, phone companies will begin to offer a technology called ADSL (asymmetric digital subscriber line) that will bring fast network access through the copper wires that still connect virtually every home to the phone network. Anyone within a few miles of a phone switching center can get the benefits of ADSL-connection rates exceeding today’s fastest modems by some 20-fold. And an ADSL connection is like an electrical socket: It’s always on.
ADSL works because most households need high-speed connection in only one direction. ADSL grants the high downloading speed by splitting the information stream in two-a low-frequency channel for voice and a high-frequency one for data. This separation allows the copper to carry data at speeds of up to 7 megabits per second in one direction without interfering with the voice conversations that occupy the same wires.
The idea for ADSL is not new. But phone companies have until now treated it as an exotic service, and it has required installing an electronic filtering device, or “splitter,” at each home.
To accelerate ADSL’s penetration into the consumer market, a host of computer and telecommunications companies have joined forces to push for a new standard that would eliminate the need for the splitter-although by limiting data rates to less spectacular speeds. The so-called “universal ADSL” would permit downloads at 1.5 megabits per second and upstream transmission at 500 kilobits per second.
Leading the drive for universal ADSL is a coalition of three dominant players in the personal computer industry-Compaq, Intel, and Microsoft-and several regional phone companies. Telephone companies will probably be conducting trials of the service by year’s end, and widespread availability should begin sometime in 1999.
ADSL should have an edge over another telephone technology-ISDN (integrated services data network), which provides only 128 kilobits per second. This latest ingredient in the telecommunications alphabet soup should provide more substantial nourishment.
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