MULTIPLEXERS, DIGITAL-TO-ANALOG CONVERTERS, ELECTRONIC FILTERS WHICH REMOVE HIGH SPEED DATA TRAFFIC FROM VOICE FREQUENCY SIGNALS ON COPPER TELEPHONE LINES, CONCENTRATORS, ANALOG-TO-DIGITAL CONVERTORS, ELECTRONIC SPLITTERS WHICH SEPARATE HIGH SPEED DATA TRAFFIC FROM VOICE FREQUENCY SIGNALS ON COPPER TELEPHONE LINES, TRANSCEIVERS, MODEMS, CONVERTORS, DIGITAL SUBSCRIBER LINES ROUTERS, COMPUTER NETWORK ROUTERS, DIGITAL CROSS-CONNECT UNITS; BRIDGES WHICH CONNECT TWO NETWORKS WITH THE SAME COMMUNICATION PROTOCOLS, FREQUENCY DIVIDERS, SYNCHRONOUS OPTICAL NETWORK/SYNCHRONOUS DIGITAL HIERARCHY ANALYZERS (SONET-SDH DEVICE); AND ASYNCHRONOUS TRANSMISSION MODE NETWORK