AT&T Co, Pacific Bell Inc and Southwestern Bell Telephone Co are testing a new ISDN-based service that is claimed to enable users to select bandwidth on a per-call basis. The trial is to begin this quarter and continue until the middle of next year. The service enables users to chose speeds in increments of 64Kbps, from 128Kbps to 1.536Mbps, and applications including videoconferencing, bulk data transfer, desktop multimedia and interactive data transfer via local network connections. The companies say that at a later date they will name the customers and suppliers involved in the trial. A Pacific Bell intraLATA Wideband ISDN trial, already under way, is using speeds of 384Kbps and 1.536Mbps, while late last month, Southwestern Bell began a laboratory test of the technology at its Advanced Technology Laboratory in St Louis, Missouri. The company also will test the service within the Dallas LATA at speeds of 128Kbps to 1.536Mbps, in increments of 64Kbps. The interLATA trial, which uses AT&T’s Accunet Switched 384Kbps and Switched 1.536Mbps service, is to interconnect with a Pacific Bell AT&T 4E switch in Los Angeles and a Southwestern Bell AT&T 5E switch located in Dallas. The trial is based on National ISDN-2 standards and multirate ISDN technical specifications developed by Bell Communications Research. Southwestern Bell and Pacific Bell plan to file tariffs for the service next year.
