Introduction to Telecommunications Chapter 1 Introduction to Telecommunications

Communication 1. Process that allows information to pass between a sender and receiver - or - 2. Transfer of meaningful information between two locations Meaningful implies perception

Telecommunications Tele means far off or distant Telecommunications today means communication by electrical or electromagnetic means, usually over a distance

Data Communications Subset of telecommunications excluding analog signals Non much analog these days

Data vs. Information Data - representation of facts, concepts, etc. suitable for communication Information - meaning associated with data

Telecommunications Elements May have multiple transmitters in a system Form networks Rules or protocols Example: establishing communications requires Initiation Identification of sender and receiver Order of communication

Basic Telecom System Elements

Telecom and Business Business must move data and voice information within locations and between locations Timing Information must be available when needed Telecom advances are revolutionizing information transfer Competitive business must maximize use of information for marketing and productivity enhancement Transactions Airline reservations, banking, marketing Used for availability, location, shipping accounting Online business: E-commerce

Telecom and Business Reduces effect of geography Link remote branches with voice/data/video Mobile communications Telecommuting

Telecom Examples

Telecom Examples

Telecom Examples

Telecom Examples

Telecom Examples

Telecom Examples

Telecom System Requirements (Data System) Availability System ready and operating when needed Reliability System trouble free and error free Real time or real-enough time Response time System does not hinder user by introducing too much delay Ease of use Ergonomics Flexibility and scalability System easy to change to meet future needs

Availability Variable requirements Time zone effects Some applications need round-the-clock availability Some businesses operate 8am to 5pm Time zone effects Must take into account working hours in other locations you must communicate with, nationally and internationally

Reliability MTBF - mean time between failure MTTR - Mean time to repair How long does it take to repair system? Reduce effects of failure with redundant (backup) components

Reliability Example 1 Overall reliability in a cascaded system is always lower than the least reliable component

Reliability Example 2

Telecommunications Timeline

Key Telecom Events 1847 - Telegraph 1877 - Telephone 1885 - American Telephone and Telegraph Company (AT&T) formed 1895 - Radio 1934 - Communications Act of 1934 (FCC) 1939 - Television 1947 - Microwave communications 1956 - First transatlantic telephone cable TAT-1 1957 - Satellite 1960s Computer/Terminal communications

Key Telecom Events 1969 - ARPANET An experimental data network 1970 - Fiber optics 1970s - Dial-up computer communications 1978 - Cellular phone 1981 - IBM PC 1984 - AT&T Divestiture 1980s - LAN 1990 - World Wide Web (WWW) 1996 - Telecommunications Act of 1996 1990s - Intranet, Extranet, E-Commerce, growth of wireless Late 1990s - media convergence

Internet Timeline

Key Internet Events 1961 - Leonard Kleinrock publishes paper on packet switching 1969 - ARPANET test 1970 - Network Control Protocol (NCP) implemented on ARPANET 1971 - E-mail 1974 - Kahn and Cerf publish paper on TCP/IP 1974 - 62 hosts on ARPANET 1979 - USENET newsgroup network

Key Internet Events 1983 - Internet Activity Board (IAB) created to oversee protocol development 1983 - TCP/IP version 4 adopted for ARPANET 1983 - 500 hosts 1984 - Domain Name System (DNS) 1986 - National Science Foundation Network (NSFNET) 1988 - Worm virus 1988 - Computer Emergency Response Team (CERT) 1990 - ARPANET retired

Key Internet Events 1991 - Gopher menu-driven Intenet interface 1991 - Tim Berners-Lee develops World Wide Web 1992 - 1,000,000 hosts 1993 - Mosaic graphical WWW interface 1993 - Internet Network Information Center (InterNIC) 1993 - 2,000,000 hosts 1995 - NSF stops supporting NSFNET Internet goes commercial Internet Service Providers (ISPs)

Key Internet Events 1995 - NSF starts supporting Very-High-Speed Backbone Network Service (vBNS) 1996 - Telecommunications Act of 1996 1996 - 10,000,000 hosts 1997 to present - E-commerce, distance learning, Voice-Over-IP, Virtual Private Networks, etc.

Major Internet Components Backbone Main infrastructure of Internet Main nodes connected by T1, T3, OC3, OC12 links Backbone routers Packet switches route data A DSU/CSU (Data Service Unit / Channel Service Unit) interfaces router to backbone Internet Service Provider (ISP) Company that links many users to backbone

Major Internet Components Concentrator Interfaces several network technologies in a single chassis Similar to a router Site Router Also known as an Access Router or Premise Router Connects a customer-s computers to the ISP

Major Internet Components T. Fallon, The Internet Today, Upper Saddle River, NJ, Prentice Hall, 2000

Case Study - Dow Corning Headquarters in Midland Michigan Business Develop, manufacture, and market silicones and related products Business structure requires close coordination between marketing, manufacturing, etc. Telecom at Dow Corning Responsibility lies within corporate Information Technology (IT) department Data and voice responsibilities brought under same group in 1982

Case Study - Dow Corning Data and voice responsibilities brought under same group in 1982 1991 - emphasis on interaction between CIS department and telecom people in manufacturing areas Network (in 1999) 11,000 personal computers and terminals 5,800 in U.S. Goal to provide rapid response time for most transactions

Case Study - Dow Corning

Case Study - Dow Corning