Telecomunications & networks hussain
[...]... linkage of workstations, peripherals and computers into networks Networks are valued by organizations because they promote the exchange of information among computer users (many business activities require the skills of many people), the collection of data from many sources and the sharing of expensive computer resources Networks may be: 1 Local area networks (LANs) which permit users in a single building... (1991) Computers, networks and the corporation Scientific American, 265(3), 128 136 Nazem, S (1993) Telecommunications and the information society: a futuristic view Information Management Bulletin, 6(1 & 2), 3 19 Sankar, C.S., Carr, H and Dent, W.D (1994) ISDN may be here to stay But it’s not plug-and-play Telecommunications, 28(10), 27 33 Sproul, L and Kiaster, S (1991) Computers, networks and work... technologies include the many devices that make telecommunications possible by contributing to the transport of messages over networks One set of such devices include the bridge that connects homogeneous (similar) networks and the gateway that connects non-homogeneous (dissimilar) networks One device that determines the route (path) that a message takes across switches, bridges (and/or) gateways is the... host (normally a mini or mainframe) or share peripherals 2 Linked LANs within a small geographic area 3 National networks such as ARPANET to link computer users in locations across the country Database services also fit into this category 4 International (wide area) networks, the most expensive networks because of long distances between nodes; the most difficult to implement because standards and regulations... But generally networks contain a mix of equipment from different manufacturers which complicates information exchange This is discussed further later in this chapter We now look at equipment configurations and technology to support teleprocessing and networks Star Ring Star-Star Ring-Star = Host computer = Node computer Bus Figure 2.1 Examples of DDp configurations Teleprocessing and networks Transmission... transmission facility is a private data network Such networks are economically feasible over short distances, which explains why they are called local area networks (LANs) Some LANs are vendor specific: that is, they support connectivity only between hardware manufactured by one manufacturer or manufacturers of compatible equipment Examples of such networks include IBM’s token ring network, Wang’s Wangnet,... Chapter 20 Networks in the 1990s The 1980s was a decade in which a large number of LANs were installed In the 1990s, many of these LANs will be joined into national and international networks Already the rewiring of Europe and the USA is under way to create a coast-to-coast network to carry voice, images and data messages simultaneously over the same line at low cost How will these integrated networks. .. (Global Area Network) (Ch 6) Internet (Ch 20) WAN (Wide Area Network) (Ch 6) MAN (Metropolitian Area Network) (Ch 6) LAN (Local Area Network) (Ch 5) ARPANET (Ch 5) Figure 1.3 Spiral of networks 3 Telecommunications and networks Part 1 of this book Part 2 is concerned with the management of these technologies We start in Chapter 9 with the location and organization of telecommunications as part of IT... at customer premises and allows AT&T to offer tariffed data services and computer companies to offer non-tariffed communications services Introduction 1981 IBM introduces the personal computer, PC 1982 Equatorial Communications Services buys two transponders and the Weststar IV satellites, giving birth to the first very small aperture service (VSAT) industry 1984 AT&T divests ownership in local telecoms... place the many components of the technology of telecommunications and networks The first of these technologies to be examined is transmission The earliest transmissions were by telephone for voice and telegraph for the written word Telephones and telegraph were complemented by post and organized as a utility better known as the PT&T (Post Telephone and Telegraph) In the USA and UK, these services have . Telecommuting at American Express 228 Case 19.4: Advice from teleworkers 228 Case 19.5: Teleworking at AT&T 228 Case 19.6: Teleworking in Europe 228 Case 19.7: Telecommuting in the US (in 1994) 229 Case. Telephones and tele- graph were complemented by post and organized as a utility better known as the PT&T (Post Tele- phone and Telegraph). In the USA and UK, these services have been privatized