Technology Guide4培训课件.ppt

,, ,, ,, ,, ,, ,, Technology Guide 4 Information Technology For Management 4th Edition Turban, McLean, Wetherbe Lecture Slides by A. Lekacos, Stony Brook University John Wiley Sons, Inc. Telecommunications Telecommunications Telecommunications generally refers to all types of long-distance communication that uses common carriers, including telephone, television, and radio. Data communications is the electronic collection, exchange, and processing of data or information, including text, pictures, and voice, that is digitally coded and intelligible to a variety of electronic devices. Telecommunications System The major components are: Hardware—all types of computers (e.g., desktop, server, mainframe) and communications processors (such as a modems or small computers dedicated solely to communications). Communications media—the physical media through which electronic signals are transferred; includes both wireline and wireless media. Communications networks—the linkages among computers and communi-cations devices. Communications processors—devices that perform specialized data commu-nication functions; includes front-end processors, controllers, multiplexors, and modems. A telecommunications system is a collection of compatible hardware and software arranged to communicate information from one location to another. Telecommunications System Continued Communications software—software that controls the telecommunications system and the entire transmission process. Data communications providers—regulated utilities or private firms that provide data communications services. Communications protocols—the rules for transferring information across the system. Communications applications—electronic data interchange (EDI), telecon-ferencing, videoconferencing, e-mail, facsimile, electronic funds transfer, and others. Electronic Signals Telecommunications media can carry two basic types of signals: Analog signals are continuous waves that “carry” infor-mation by alt