Anyone looking for a crisp and concise description of the evolution of data switching technology since the mid-sixties will find this chapter to be interesting and informational. Also discussed are the motivations and underlying reasons for the development of various products in the evolution chain. An additional fringe benefit to the reader is that this chapter outlines criteria for selection of a data-switching technique to meet given user requirements.

Beginning with the analog circuit switching technology used in the public voice network, this chapter traces the evolution of packet-switching technology. This technology resulted from government sponsorship for the development of ARPANET to overcome the limitations of analog switching. The historical examination of the evolution continues into the discussion of the Datagram Protocol and its limitations, Virtual Circuit Switching, Integrated Packet and Circuit Switching, and future perspectives. The chapter ends with a list of the issues and requirements that will have major impact on the development of the switching technology in the 1980s. A fairly impressive list of references accompanies the chapter.