Telecommunications

Birth of Telecommunications

Telecommunications began as a one-to-one form of communicating over geographic distances. The telegraph, which came into commercial operation in the late 1840s, was the first modern-day example of this form of communications. Because the telegraph required trained personnel at both ends of the line, all communication between individuals had to be processed through telegraph operators. The invention of the telephone in the mid-1870s eventually supplanted telegraphy, allowing users to communicate directly with one another.

The telephone was the first technology to allow a human voice to be transmitted over significant geographic distances. Until the late 1890s, telephone callers were limited to a relatively small geographic area. The growth of telephone networks required many supplementary inventions, notably the ability to switch calls. Although it was initially limited to short distances, telephone technology evolved to allow coast-to-coast calls across the United States by 1915. In parallel with this, automatic switching exchanges began to supplant human operators as early as 1900, although manual exchanges persisted in the United States for many decades to come.

Digital Telephony

In the 1960s, digital transmission technologies were introduced into the long distance telephone network. These were followed in short order by digital switches. These technologies allowed for improved telephone transmission quality. Today, all domestic long distance calls and many local calls are carried digitally over fiber optic networks. Internationally, some calls are still carried by satellite-based communications systems while others are transmitted via undersea fiber optic cables.

Other developments in telephony include the introduction of wireless communications for the purpose of mobility. Although these systems had been available for a very limited number of users as early as the 1950s, the development of cellular communications systems in the 1970s and 1980s enabled many more users to obtain the benefits of mobile telephone systems. By the 1990s, these systems had become widely available and very popular worldwide.

Broadcast Telecommunications

The broadcasting industry began in the 1920s as the ability to transmit speech via wireless radio became economically feasible. Prior to this, communications technology was limited to one-to-one communications—that is, one person communicating with exactly one other person. The transmission of speech over wireless systems made it possible for one sender to communicate with many receivers. Thus, one of the distinguishing features of broadcasting is that it is a one-to-many form of communication.

Until the 1950s, broadcasting and wireless communications were synonymous. All programming signals were transmitted to individual antennas that were either built in to televisions and radios or added to buildings to enhance signal reception. Around that time, communities in rural and mountainous areas, where it was difficult to receive over-the-air broadcast signals, began installing Community Antenna Television (CATV) systems. In these systems, a community would pool their resources to invest in an expensive antenna that was designed and placed for good signal reception. These superior signals were then distributed throughout the community via cables. Operators of cable systems gradually expanded their infrastructure and began to offer a rich variety of programming on these cable-based systems, making them attractive to viewers beyond their original service markets. Today, the majority of American communities are wired to provide television programming via cable systems.

Computer-Based Telecommunications

The computer networks of today had their genesis in the dedicated teleprocessing systems of the 1960s. These early computer networks were designed to support terminals communicating with a central mainframe computer. In the late 1960s, researchers began experimenting with different types of networks; ones that allowed any device on the network to communicate with any other device. Networks of this kind are called "peer-to-peer" networks, as each computer has the same operational privileges as any other computer.

As minicomputers became popular in the 1970s, networks of this kind expanded to meet new business needs and applications. Peer-to-peer networking accelerated with the development of local area networks (LANs) and microcomputers, better known as personal computers, in the 1980s. Concurrent with these developments in local network technologies, work continued on new systems such as wide area networks (WANs) that would be capable of interconnecting these LANs. The most ubiquitous and successful of these networks is the Internet.

The Internet is a network of networks designed to interconnect general purpose computers. The Internet was designed to be application-transparent, so users could develop any kind of networked application without having to make changes to the network. Thus, when the World Wide Web was developed in the late 1980s, the network could easily accommodate it. All that was needed were application programs in computers, called browsers, and hardware systems containing information, called servers, to be attached to the network. Despite many advances in technology and exponential growth in the number of computers on the network, the basic structure of the Internet remains intact.

Telecommunications Industry Challenges

The telecommunications industry is facing new technological pressures from the phenomenon of convergence. Since all major forms of communication are now transmitted primarily with digital technology, it is a relatively small matter for any of the network types—CATV, telephone, or computer—to carry any type of information. So, for example, although CATV systems were originally designed for broadcast television service, technologies have converged such that cable systems carry not just television programming, but also high speed data for computer use and voice data for telephony.

The evolution of telecommunications has changed more than the physical aspects of our telecommunications networks. Along with the technological changes described earlier, dramatic changes have occurred in the way telecommunications companies do business in this industry, as well as in the way governments regulate the various networks. Advances in technology and evolving user expectations will continue to drive change in the telecommunications industry.

SEE ALSO APPLE COMPUTER, INC.; BELL LABS; INTEL CORPORATION; MICROSOFT CORPORATION; XEROX CORPORATION.

Martin B. Weiss

Bibliography

Carne, E. Bryan. Telecommunications Primer: Data, Voice, and Video Communications. Upper Saddle River, NJ: Prentice Hall, 1999.

Dodd, Annabel Z. The Essential Guide to Telecommunications, 3rd ed. Upper Saddle River, NJ: Prentice Hall, 2001.

Green, James H. The Irwin Handbook of Telecommunications Management, 3rd ed. New York: McGraw-Hill, 2001.