2.22: Four Generations of Telecommunications

Innovations in computer technology, as described above, are providing us with better "tin cans", innovations in telecommunications technology is providing us with better "strings".

Whereas innovations in computer technology is best understood as five generations of computers, each of which supplants the previous ones, innovations in telecommunications technology is best understood as four "generations" of communication channels, each of which supplements the previous ones.

The first generation is characterized by the natural channels of audition and vision. You speak and I listen. You gesture and I look. This generation is limited in the distance over which communication is possible. I must be within earshot or eyesight of you.

In the second generation, information is physically packaged in some object, which is created by you and interpreted by me. You write and I read. You take photographs and I look at them. This generation extends the distance over which we can communicate. The physical objects in which your messages are embodied (letters and books, photographs and films) can be sent to me by whatever means of transportation is available (pony express, jet plane, etc.) It also extends the conquest of time as well as of space, since you can write now and I can read later. However, communication in this generation is limited to the speed of transportation.

In the third generation, information is transmitted by waves. We are back to the first generation of sound and light waves. However, this time the waves are amplified and relayed by technology. The waves can either pass through air (radio and television) or through wires (telephony and telegraph). communication is no longer limited by the speed of transportation (which has only recently exceeded the speed of sound with the Concorde Jet) but by the speed of light. A few decades ago, this third generation had penetrated industrial societies. Telephony (the prototype wire technology) and television (the prototype wave technology) had penetrated households to an asymptote of over 90 per cent.

The spate of recent innovations in communication technology has greatly enhanced this third generation. In the process, air-waves and wire-waves have got crossed. Because we tend to focus on the input/output devices which we can see, cable television is identified with television but is actually an evolution of wire technology, and cellular telephone is identified with telephony but is actually an evolution of air technology. Fibre optics has greatly enhanced the use of wire technology. More and more communication is possible at greater and greater speeds than with the copper channel. Satellites have greatly enhanced the use of air technology. You can communicate with more and more people within a wider and wider area.

The new technologies also introduce a fourth generation. The waves, whether over air or on wires, are transformed into patterns of zeros and ones. That is, analog signals are transformed into digital signals. Reducing the various analog signals to a lowest common denominator of digital signals permits the integration of the various previous channels of communication. Your voice and gestures in the first generation, your letters and photographs in the second generation, and your television images and telephone messages in the third generation, can all be integrated within the digital signals of this fourth generation.

This fourth generation also mirrors the second generation in having certain physical objects (videocassettes, videodiscs, compact discs, floppy disks, hard disks, etc.) in which information is stored. In this generation, however, the information is stored digitally and can thus be easily integrated with the communication channel which also processes information digitally. Thus, the storing of information is also integrated with the processing of information.