Computer hardware for communicating audio, video and data between computers via a global computer network, wide-area computer networks, and peer-to-peer computer networks; Computer hardware for telecommunications; Computer network adapters; Computer network hubs; Computer network interface devices; Computer network server; Computer network switches; Computer networking hardware; Electronic and optical communications instruments and components, namely, communication link testers for testing communication links; Electronic and optical communications instruments and components, namely, optical data links; Electronic and optical communications instruments and components, namely, optical receivers; Electronic and optical communications instruments and components, namely, optical transceivers; Electronic and optical communications instruments and components, namely, optical transmitters; Electronic and optical communications instruments and components, namely, digital transmitters; Fiber optic connectors; Network access server hardware; Network routers; Wireless adapters used to link computers to a telecommunications network; Computer cables; Connection cables; Data cables; Ethernet cables; Insulated copper wire; Optical fiber cables; Telecommunications cables