Contiene: Communicating by wire. The telegraph. The telephone. Printing telegraphs. Mixing computers and telephones. The early networks. From keypunches to terminals to the carterfone. Alphabet soup: morse, baudot, ASCII, and EBCDIC. The bell 103 modem. Dialing for data. The RS-232C serial interface. The personal computer as a terminal. Smart modems. The fax modem. Computer telephony integration. Local area networks (LANs). A network model. Network operating systems. The network interface card. Network cabling. Server-based LANs. Peer-to-peer networks. Enterprise network systems. Remote LAN access. Network security. Links between LANs. Repeaters, bridges, routers, and switches. Metropolitan area networks (MANs). Circuit-switched digital services. Packet-switching networks. Workgroup applications. Online information services. Electronic-mail systems. Beyond electronic mail: groupware for productivity. The internet.