UDS

MODEM SHARING DEVICES UNITS FOR INTERFACING WITH MULTIPLE DATA PORTS; AUTOMATIC CALLING UNITS; PROTOCOL CONVERTERS; DUAL-DIAL BACKUP UNITS AND ERROR CONTROLLERS UTILIZED WITH MODEMS; DATA SERVICE UNITS AND CHANNEL SERVICE UNITS UTILIZED IN THE DIGITAL DATA SERVICE NETWORK; MULTIPLE MODEM ENCLOSURES, NAMELY, EQUIPMENT RACKS; LINE DRIVERS; AND MULTIPLEXERS