Telecommunications and Networks Chapter 6 McGraw-Hill/IrwinCopyright © 2011 by The McGraw-Hill Companies, Inc. All rights reserved.

6-2 Understand the concept of a network Apply Metcalfe’s law in understanding the value of a network Identify major developments and trends in the industries, technologies, and business applications of telecommunications and Internet technologies Learning Objectives

6-3 Provide examples of the business value of Internet, intranet, and extranet applications Identify the basic components, functions, and types of telecommunications networks used in business Explain the functions of major components of telecommunications network hardware, software, media, and services Learning Objectives

6-4 Explain the concept of client/server networking Understand the two forms of peer-to- peer networking Explain the difference between digital and analog signals Learning Objectives

6-5 Network Concepts Interconnected chain, group, or system Connections created by nodes Exponential growth Metcalf’s Law –Usefulness, or utility, of a network Equals the square of the number of users More users = more useful

6-6 Network Component Alternatives

6-7 Telecommunications Media Twisted-Pair Wire –Similar to telephone wire Coaxial Cable –Wire wrapped with insulation Fiber-Optic Cable –One or more hair-thin filaments of glass

6-8 Communications Satellites –Geosynchronous orbit –Serve as relay stations Wireless LANS –Wireless radio-wave technology Bluetooth –Short-range wireless technology Other Wireless Systems –Cellular phones, Mobile radio, PDAs Telecommunications vital and pervasive –Web-enabled e-business processes Wireless Technologies

6-9 Other Wireless Systems –Cellular phones –Mobile radio –PDAs Telecommunications pervasive role –Web-enabled e-business processes –Electronic commerce –Enterprise collaboration –Other applications Business operations, management, strategic objectives Wireless Technologies

6-10 The Wireless Web Web-enabled appliances proliferate –Smart telephones, pagers, PDAs –All are very thin clients in wireless networks

6-11 Telecommunications Processors Modems –Most common type –Modulation and demodulation Converts for transmission over telephone lines Digital signal to analog Analog to digital

6-12 Telecommunications Software May reside in PCs, servers, mainframes, and communications processors –Vital part of all telecommunications networks –Used to manage network performance –WANs often use telecommunications monitors or teleprocessing monitors –Other networks use operating system software –Middleware helps diverse networks communicate with each other

6-13 Network Management Functions Traffic Management Security Network Monitoring Capacity Planning

6-14 Network Architectures and Protocols Protocol –Rules and procedures Handshaking –Exchanging predetermined to agree on a protocol Network Architecture –Master plan of standards –Goal is to promote an open, simple, flexible, and efficient telecommunications environment

6-15 OSI Model Open Systems Interconnection Model –Seven-layer standard for network architectures –Controls how messages should be transmitted –Ensures consistency among products