Audio-video receivers; building security systems comprising software and hardware for providing picture, video, alarm status, building plans, and other information to a remote station; computer hardware and software for setting up and configuring local area networks; computer hardware and software for setting up and configuring wide area networks; computer network hubs, switches and routers; computer networking hardware; computer software for administration of computer local area networks; computer software for administration of computer networks; computer software for use in the safeguarding of digital files, including audio, video, text, binary, still images, graphics and multimedia files; digital video recorders; electric and electronic video surveillance installations; LAN (local area network) computer cards for connecting portable computer devices to computer networks; LAN (local area network) hardware; network access server hardware; TV and video converters; telecommunications and data networking hardware, namely, devices for transporting and aggregating voice, data, and video communications across multiple network infrastructures and communications protocols; video multiplexers