The regional telephone companies do not now have the technology to allow more than one company to carry such calls.

All seven regional telephone holding companies are expected to offer the services by 1992; some have said they have delayed introduction of the service because of the privacy issues.

Signaling System 7 is a basic operating standard for both equipment and software used in new network systems that are being installed by all the regional telephone companies.

The regional telephone holding company's profit was $150 million, or 35 cents a share, down from $237 million, or 55 cents a share, a year earlier.

Bellcore Set Standard The standard, known as the analog display services interface, was developed by Bellcore, the regional telephone companies' joint research arm.

These executives said that the deal had not yet been completed and that other companies, including regional telephone and software companies, might participate.

The Telecommunications Act of 1996 deregulated the monopolies many regional telephone and cable television companies held.

The Bell Atlantic Corporation and the Southwestern Bell Corporation, two regional telephone holding companies, yesterday reported lower earnings for the fourth quarter.

In 2002, SBC Communications dropped its regional telephone company names, switching to a unified "SBC" brand.

Lawmakers are debating legislation that would continue restrictions in the antitrust consent decree that bar the regional telephones from manufacturing equipment, providing information services or entering the long-distance business.