COMPUTER HARDWARE AND SOFTWARE FOR THE MANAGEMENT, ANALYSIS, TROUBLESHOOTING, MEASURING, AND MONITORING OF COMPUTER AND TELECOMMUNICATION NETWORKS; ELECTRONIC AND OPTICAL COMMUNICATIONS INSTRUMENTS AND COMPONENTS; NAMELY, OPTICAL TRANSMITTERS, OPTICAL RECEIVERS, OPTICAL DATA LINKS, OPTICAL TRANSCEIVERS, HOST BUS ADAPTERS, TRANSPONDERS, TAPS, AND COMMUNICATION LINK TESTERS FOR TESTING COMMUNICATION LINKS