This text aims to provide an intelligent near-beginner (as far as OSI is concerned) with an understanding of Open Systems Interconnection (OSI). Some previous acquaintance with data communications as presented in the many text books on that broad subject would be useful.
The book is aimed at the reader who is curious enough to ask: "Why is it that way? What advantages does that approach give? Might there be other or better ways?" This text is not an exposition of the technical detail of the OSI Standards. Rather it aims to explain why OSI is the shape it is, and to guide the reader in a critical examination of the OSI approach to specifying rules for computer communication (computer protocols).