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Business Data Communications, Fourth Edition. Chapter 1: Introduction to Communications. Learning Objectives. Define data communications Describe the difference between data communications and telecommunications
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Business Data Communications, Fourth Edition Chapter 1: Introduction to Communications
Learning Objectives • Define data communications • Describe the difference between data communications and telecommunications • Define local area networks, wide area networks, metropolitan area networks, wireless networks, and personal area networks • Understand the components of a communications system Chapter 1: Introduction to Communications 2
Learning Objectives • Describe the role of, and list, regulatory agencies in data communications • List the standards-setting organizations involved in the communications industry • Explain how the government uses communications networks Chapter 1: Introduction to Communications 3
Introduction • Communications began from primitive methods • More efficient communications were needed with the advance of the industrial age • The telegraph began the age of electronic communications • Voice, video, and data transmitted in modern communications systems Chapter 1: Introduction to Communications 4
What is Data Communications? • Transmission of data over a network • Subset of telecommunications • Networks • Telephone system • May connect computers and related devices • PC prices have dropped • Data communications network • Computers and related devices • Devices and lines used to connect the devices Chapter 1: Introduction to Communications 5
What is Data Communications? • Networks • Types of networks • Wide area network (WAN) • Local area network (LAN) • Metropolitan area network (MAN) • Internet • Wireless networks • Personal Area Network (PAN) Chapter 1: Introduction to Communications 8
Basic Components of a Communications System • Three physical components • Source (or sender) • Medium • Receiver • One Software component • Protocol • Circuit • Example – Drive-up bank window Chapter 1: Introduction to Communications 14
The Telephone System • Telegraph – 1840 • Telephone – 1876 • AT&T was a monopoly • Positive aspects of standardization • Divestiture in 1984 • Data communications and the telephone system Chapter 1: Introduction to Communications 16
The Telephone System • Common Carriers • Profit-oriented companies • Over 1200 in the United States • Cellular service providers • Local and long distance service • IntraLATA Calls • Local Access Transport Areas (LATAs) • Local and “local long distance” Chapter 1: Introduction to Communications 18
The Telephone System • InterLATA Calls • Long distance calls • May or may not use a carrier different from the one offering local telephone service • Divestiture has allowed all companies to compete in both local and long distance markets • Slamming – unauthorized switch to a different phone company Chapter 1: Introduction to Communications 20
Governmental and Regulatory Agencies • Federal Communications Commission (FCC) • Created in 1934 • Prior to that time, the Interstate Commerce Commission controlled communications • Regulates interstate and international telecommunications • Tariff schedules Chapter 1: Introduction to Communications 21
Governmental and Regulatory Agencies • Public Utility Commissions • Regulate intrastate communications • Regulate common carriers within a state • Rates charged can differ by state • Negotiates when conflicts arise, if the problem is completely within a single state Chapter 1: Introduction to Communications 22
Governmental and Regulatory Agencies • National Telecommunications and Information Administration (NTIA) • Branch of the U.S. Department of Commerce • Catalyst for innovation in communications industry • Helps create jobs in that sector • Establishes grants to create a communications infrastructure for all citizens Chapter 1: Introduction to Communications 23
Standards Organizations • American National Standards Institute (ANSI) • Creates voluntary national standards • Has over 1,000 members • Works to create consensus on standards among all the groups • Publishes standards created by other organizations • Creating a standard for FDDI Chapter 1: Introduction to Communications 24
Standards Organizations • International Organization for Standardization (ISO) • Non-electronic telecommunication standards • Created the Open Systems Interconnection (OSI) 7-layer model • Corporation for Open Systems • Promotes the use of equipment that meets ISO standards Chapter 1: Introduction to Communications 25
Standards Organizations • International Telecommunication Union (ITU) • Equipment standards in other countries • Provides technical assistance in setting up communications systems in third world countries • International Telecommunication Union-Telecommunication Standardization Sector (ITU-T) • Fosters cooperative standards for telecommunications equipment and systems • Took over functions of the CCITT Chapter 1: Introduction to Communications 26
Standards Organizations • Institute of Electrical and Electronics Engineers (IEEE) • An ANSI member organization • Standards developed for the lowest two levels of the OSI model • Developed standards for local area networks Chapter 1: Introduction to Communications 27
Standards Organizations • Electronics Industries Association (EIA) • Sets electrical standards • Members are manufacturers of electrical equipment • Developed standards for the lowest level of the OSI model • Telecommunications Industry Assn. (TIA) • Members are companies that provide communications and other IT products and services • Acts as a voice on public policy and international matters that affect its members Chapter 1: Introduction to Communications 28
Standards Organizations • Committee T1 • Provides standards for interfaces • Accredited by ANSI • Addresses issues related to interconnection of customers to public communications carriers • Personal Communications Industry Association (PCIA) • Trade association for the personal communications services industry • Regulations and standards related to wireless communications Chapter 1: Introduction to Communications 29
Standards Organizations • Cellular Telecommunications Industry Association (CTIA) • Conducts surveys on use of cellular technology • Communications Satellite Corporation (COMSAT) • Coordinates use of satellites among countries, and represents the USA • International Telecommunications Satellite Organization (INTELSAT) • Coordinates use of satellites internationally Chapter 1: Introduction to Communications 30
Applications of Data Communications • Computer system processing • Early systems • Batch • No networks • Modern systems • On-line • Networks Chapter 1: Introduction to Communications 31
Applications of Data Communications • Government Applications • Original use – Census data collection in 1950 • Internal Revenue Service (IRS) • National Aeronautical and Space Administration (NASA) • Military uses • The Internet • E-Commerce Chapter 1: Introduction to Communications 34
Chapter Summary • Rapid increase in communications • Data transmission • Three components of communications • Common carriers • FCC and PUCs • Regulatory agencies • Common uses for communications networks Chapter 1: Introduction to Communications 35