Telecommunications Overview Chapter 1
Objectives In this chapter, you will learn to: • Define communication and telecommunication • Illustrate components of a communication system • Understand the difference between voice, video, and data • Identify careers available to telecommunications professionals • Identify the organizations responsible for establishing significant telecommunications standards and policies
Elements of a Communication System • Source - the originator of the message, whether it is a person or machine. • Transmitter - the equipment that modifies the message (either data or voice) into the form required for transmission. • Communications channel - the means of carrying the signal from the source to the destination.
Elements of a Communication System • Transmission media - may be physical, like a copper wire or fiber optic cable, or atmospheric, like radio waves. • Receiver - is the device that captures the message from the communications channel and converts it into a form that the person or machine at the destination can understand. • Destination - the person or machine to whom the message is directed
Flow of Messages • Simplex - the type of communication in which messages flow in only one direction, from source to destination. • Half-duplex communication - occurs when messages travel in both directions between the source and the destination, but in only one direction at a time. • Full-duplex communication - messages can travel over the communications channel in both directions simultaneously.
Relative Number of Sources and Destinations • One-to-one communication - a single source sends information to a single destination. • One-to-many communication - a single source simultaneously sends information to multiple destinations. • Many-to-many communication - occurs when many sources issue messages to many destinations.
Classification of Data Networksby Ownership Internet 1969: ARPANET was funded by the DARPA commitment to a standard communication protocol 1978: Unix-to-Unix copy program 1981: Development of CSNET and BITNET 1982: Term Internet is coined 1986: Establishment of NSFNET 1989: CSNET and BITNET merge to form CREN 1990: WWW becomes part of the Internet • Public Network • Owned by a common carrier • Private Network • Built for exclusive use by a single organization • Virtual Private Network • Encrypted tunnels through a shared private or public network
Classification of Data Networks by Switching Technology • Circuit Switching • Connection-oriented networks, ideal for real-time applications, guaranteed quality of service • Message Switching • Store-and-forward system • Packet Switching • Shared facilities, Used for data communications • Cell Switching • Fast processing of fixed length cells
Classification of Data Networks by Computing Model • Distributed Computing • Client/Server set-up • Centralized Computing • Thin-client architecture • Some Useful Telecom Terms • Scalability: Ability to increase the power and/or number of users without major redesigns • RAID (Redundant Array of Independent Disks) • UPS (Uninterruptible Power Supply)
Classification of Data Networks by Type of Information • Data Communications • Digital transmission of information • Voice Communications • Telephone communications • Video Communications • Cable TV or video conferencing
Internet • 1969: ARPANET was funded by the DARPA commitment to a standard communication protocol • 1978: Unix-to-Unix copy program • 1981: Development of CSNET and BITNET • 1982: Term Internet is coined • 1986: Establishment of NSFNET • 1989: CSNET and BITNET merge to form CREN • 1990: WWW becomes part of the Internet
What is Telecommunication? • Communication that spans a distance. • Voice telecommunication - using electrical signals to transmit human voice across a distance, such as telephones and radio broadcasts. • Video telecommunication - the electrically-based transmission of moving pictures and sound across a distance. • Data telecommunication - the use of electrical signals to exchange encoded information between computerized devices across a distance.
Types of Telecommunications Companies • Service providers - those that supply the communications channels for voice and data transmission. • Equipment providers - those that supply the user and connectivity equipment, such as telephones.
Growth of the Telecommunications Industry • The United States government recently released a report citing the number of high-speed lines connecting individuals and businesses to the Internet increased 36% during the first half of the year 2001, for a total of 9.6 million high-speed connections. • The number of minutes Americans spend on interstate long-distance telephone calls has quadrupled in the last 25 years to a total of 600 billion minutes. • As of July 2001, the number of computers that provide files and Web pages to users on the Internet had grown to over 125 million, maintaining a 63% annual growth rate.
Financial Services • Call center - a facility dedicated to fielding customer calls. • Interactive voice response (IVR) system - a method of sending information over the telephone by pressing buttons in response to recorded voice prompts, to answer routine questions. • Automatic call distributor (ACD) - uses computerized devices attached to the phone lines to automatically route calls to specific phone extensions.
Utilities • Recent deregulation (the introduction of competition for services) in the utilities industry has made telecommunications even more critical to this industry. • To persuade their customers not to choose another utility provider, utility companies must strive harder to please their customers, in part by answering questions as promptly as possible. • An advanced call center at a utilities company typically uses both an ACD and an IVR.
Manufacturing • The use of advanced voice, video, and data telecommunications in manufacturing has resulted in faster and more efficient production of goods and at the same time it has also increased global competition. • Supply chain management, an electronic means for connecting a manufacturer with its suppliers and distributors is a notable example of the use of telecommunications in the manufacturing industry.
Transportation • Examples of the transportation industry’s use of telecommunications include: • computerized flight control for airport traffic • software that issues maps and directions based on a given starting point and destination • government-sponsored transportation hotlines that inform callers about road construction and hazardous road conditions • systems for suggesting the most efficient route between multiple locations
Retail • E-business - the use of data telecommunications to conduct business transactions. • The apparel and sportswear segment of the retail industry uses particularly sophisticated and unique telecommunications technology for their online business. • Before the products even reach a retailer’s point of sale (such as a Web site), telecommunications technology helps with manufacturing, quality control, inventory, distribution, and product shipping.
Healthcare • Telemedicine - a field that brings patients and healthcare professionals together by exchanging voice, video, and data over distances when they can’t meet face-to-face. • Improves the quality of healthcare because ailments can often be diagnosed and treated faster. • Also streamlines the record-keeping process for clinicians who spend a great deal of time entering data about their cases.
Government and Education • Many government agencies use advanced telecommunications to provide faster and easier access to public services. • Telecommunications also plays a significant role in education. In South Carolina, a large public school district is improving education through distance learning. • Distance learning - the use of telecommunications technology to inform, educate, or train students across distances.
New Frontiers for Telecommunications Technology • Fiber optic cable - a transmission media that contains thin strands of fiber in its core and uses pulses of light to convey signals. • Capable of carrying higher amounts of data, voice, or video within a given time span than any other type of media.
Careers in Telecommunications • No matter what type of telecommunications position you seek, the following will serve you well: • The ability to install, maintain, and troubleshoot the system of cables and wires that carry telecommunications services • A thorough knowledge of the public telephone network, and the carriers and regulations that are part of it • Familiarity with enhanced telephone services (such as IVR and ACD) • A mastery of the basic principles of electricity
Careers in Telecommunications • No matter what type of telecommunications position you seek, the following will serve you well: • A clear understanding of how computers accept and interpret data from other computers over a network • The ability to design, install, and troubleshoot basic networks • An understanding of how the Internet works • Familiarity with wireless transmission methods
Careers in Telecommunications • Areas within the field of telecommunications that you might consider specializing in: • Networked convergence of voice, video, and data • Electronics and circuit design and engineering • Development of telephony and computer applications • Wireless telephony and networking • Information security
Careers in Telecommunications • Wide variety of opportunities in diverse fields • Life sciences, business office, movie & game industry, manufacturing, telecom companies • Telecom engineers and technicians • Hardware • Software • Network administration • Security management • Storage management • Project management
Telecommunications Standard Organization • Standards - documented agreements containing technical specifications or other precise criteria that stipulate how a particular product or service should be designed or performed. • American National Standards Institute (ANSI) - ensures that the test results from one manufacturer can be accurately compared to other manufacturers’ results. • Both ANSI and ITU are involved in setting standards for Integrated Services Digital Network (ISDN) communications.
ANSI • The ANSI (American National Standards Institute) - an organization composed of over a thousand representatives from industry and government who together determine standards for the electronics industry. • ANSI does not dictate that manufacturers comply with their standards, but requests them to voluntarily comply.
TIA and EIA • The EIA (Electronics Industry Alliance) - is a trade organization composed of representatives from electronics manufacturing firms across the United States. • TIA (Telecommunications Industry Association) - focuses on standards for information technology, wireless, satellite, fiber optics, and telephone equipment.
IEEE • IEEE (Institute of Electrical and Electronic Engineers) - an international society composed of engineering professionals. • Its goals are to promote development and education in the electrical engineering and computer science fields.
ATIS • ATIS (The Association for Telecommunications Industry Solutions) - a North American trade association made of thousands of companies that provide communications equipment and services. • Its membership reviews emerging technology and agrees on standards and operating procedures to ensure that services and equipment supplied by multiple companies can be easily integrated.
ISO • ISO (International Organization for Standardization) - a collection of standards organizations representing 130 countries with its headquarters located in Geneva, Switzerland. • Its goal is to establish international technological standards to facilitate global exchange of information and barrier-free trade.
ITU • The ITU (International Telecommunications Union) - a specialized United Nations agency that regulates international telecommunication usage, including radio and TV frequencies, satellite and telephony specifications, networking infrastructure, and tariffs applied to global communication. • Provides developing countries with technical expertise and equipment to advance their technological base.
Standards • De facto Standards • Open Computing
Summary • Communication is the conveyance and understanding of meaningful information from one entity to another. • Data telecommunication refers to use of electrical signals to exchange encoded information between computerized devices across a distance. • Within the field of telecommunications, professionals typically divide its services into three categories: voice, video, and data. • The telephone is the primary means of transmitting and receiving voice signals.
Week 1 Links • www.privateline.com/TelephoneHistory/History1.htm • www.bellsystemmemorial.com/westernelectric history.html • www.bellsystemmemorial.com/bellsystem history.html • www.tecomhistory.org • www.museumphones.com/index.html#t • www.althosbooks.com