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Full-motion video on phone lines

A new technology promises to allow PCs to send and receive full-motion, high-quality video over ordinary phone lines.

    Start-up Objective Communications (OCOM) has developed a new technology that will allow PCs to send and receive full-motion, high-quality video and data communications over ordinary telephone lines, thereby freeing up network bandwidth.

    Objective says companies will be able to receive television broadcasts and video training materials on their PCs or work collaboratively on materials without causing congestion on local company networks

    Companies that want videoconferencing can add bandwidth in the form of a dedicated high-speed link to each desktop, a costly proposition. They can also reduce the network traffic to accommodate the large amount of information required for video transmission, but quality can still be degraded if, for instance, another large file is transferred over the network at the same time.

    Objective says companies can bypass such problems by using their technology, called VidModem. It uses a proprietary technology to transmit digital data over regular phone wires, and can be used with PBX (public branch exchange) or Centrex phone systems.

    "Most MIS managers are reluctant to allocate part of their LAN's bandwidth to video images because of the potential bottlenecks," said Bettina Tratz-Ryan, an analyst with Frost and Sullivan, in a statement. "VidModem is unique in its ability to deliver full-screen, broadcast-quality images without having to dip into the LAN."

    VidModem converts first install a high-speed switch that can be configured for 20, 30 or 50 users and then install the modems on desktops with Macs, PCs, or Sun workstations, which are typically connected to a LAN as well.

    Objective claims that its digital modems use a special modulation technique which can deliver uncompressed digital data, including audio and video, at 270 Mbps from the switch to desktops up to one-quarter mile away. That range accommodates most desktops in a high-rise building. Ethernet networks, by contrast, can only span a distance of 328 feet, and are limited to 100 Mbps.

    Companies still need a high-speed link if they want to connect to networks or other users that are more than one-half mile apart. Objective says the switch can receive video and data signals from digital satellite systems and cable, ISDN, or ATM connections, with download speeds limited by the connection technologies.

    Objective says they have installed demonstration systems at companies such as Sprint and Bell Atlantic, as well as for the Navy. The system will be available for commercial shipment in the fourth quarter of this year, the company said, at a price close to that of ISDN-based videoconferencing systems.