Some notes on the history of protocol engineering

During the 1970s and 1980s, the first computer communication networks were designed and implemented in the research and commercial sectors. Many of the protocols developed during that time are still in use today. This paper starts by giving an overview of these developments. Then it concentrates on the development of protocol engineering, that is, the methods for the specification of communication protocols and services, the verification of protocols and their implementation and testing. After personal views of the developments in the 1970s, the basic concepts developed at that time are explained. The standardization of Formal Description Techniques in the 1980s is discussed in the following section, as well as the standardization of conformance testing. The purpose of the paper is to show the long way we have come and to suggest that many of the basic concepts have not changed too much during these years, although more detailed aspects have evolved and given rise to new technological developments.