Реферат: ADSL Essay Research Paper Overview

then be used for video on demand, instant replay, broadcast TV, interactive

games, home shopping, and educational data bases. But the cost of the

boxes to provide the service was still high.

In mid-1995, a new version of ADSL, called V-ADSL, was introduced. V-ADSL

was designed to work in conjunction with FTTC network architecture. As

telcos brought fiber closer to the homes, the telcos could use V-ADSL

as the last connection to the home or business. With shorter distances

being covered by copper wire, V-ADSL could provide higher bit rates, 51

Mbps for distances of about 1000 feet and 25.6 Mbps for distances of 3000

to 4000 feet.

By early 1996, the benefits of using ADSL for Internet access were being

explored. GTE Corporation began

a test in the Dallas-Ft. Worth area in February using residential customers,

high-traffic public areas, and small businesses. In the third quarter,

US West began a trial in Denver and

Boulder, Colorado and Minneapolis-St. Paul, Minnesota. US West’s

trial was designed to link users to the Internet and corporate intranets.

New Competitors Line Up

With the success of these trials and the potential cost savings being

demonstrated, several additional vendors began developing the transceiver

boxes necessary to support ADSL. In May, 1996, Motorola

announced plans to release a single-chip device designed to enable video-on-demand

and Internet access by early 1997. Motorola’s ADSL chip would be

capable of speeds up to 8 Mbps.

In July of 1996, Bell Canada announced

that it would be offering widespread ADSL service by early 1997 and Amati

Communications Corporation previewed its Ethernet-compatible ADSL modem.

Amati’s modem provided bit rates of 8 Mbps at distances up to 12,000

feet and 1.5 Mbps up to 15,000 feet. In addition, Amati announced the