Early Provisioning for xDSLs

Telephone companies are rolling out ADSL services cautiously. This fact has given pioneering ISPs an opportunity to offer some forms of DSL service in advance of the telcos' proposed ADSL services. Also, some corporations have considered implementing DSL services over private phone wires already installed in their buildings and industrial parks.

A popular underground method of obtaining DSL service is to order dry pair wires from the telephone company and put ATU-C and ATU-R components on it. A dry pair is phone wire with no electronics from one end to the other. A dry pair may pass through a telco office, but it doesn't touch telco equipment. It is referred to by a variety of names by different telcos, including the following:

• Burglar alarm wire

• Local Area Data (LAD) circuit

• Modified metallic circuit with no ring-down generators

• Voice-grade 36 circuit

Controversy surrounds recent decisions by some LECs to terminate the availability of dry copper wires, resulting in frustrating attempts by some ISPs to offer early xDSL services. Public hearings in the western United States, for example, are proceeding on petitions by U.S. West to stop offering LAD service.