ASN.1 (Abstract Syntax Notation One) is an international standard which aims, at specifying of data used in telecommunication protocols. It is a computing, language that is both powerful and complex: it was designed for modeling, e±ciently communications between heterogeneous systems., ASN.1 was in great need of a reference book, didactic as well as precise, and Olivier Dubuisson's book meets these demands. The language is comprehensively, described from its basic constructions to the latest additions to the, notation. The descr iption of each of these constructions is wholly accessible, and accurate. Many case studies of real-world applications illustrate this presentation., The text also replaces the language in its historical background and, describes the context in which it is used, both from the application viewpoint, and from that of other speci¯cation standards which use or refer to ASN.1., This book is written by an expert of ASN.1, of its syntax and semantics,, and clearly constitutes a reference on the language. It is intended for those, merely interested in ¯nding a complete and reliable description of the language, and for programmers or experts who may want to look up for the proper usage, of some constructions. The tools available on the website associated with this, book will prove useful to both the pro¯cient and the beginner ASN.1 user., Michel Mauny, Project leader at INRIA, the French National Institute for Research in, Computer Science and Control iption of each of these constructions is wholly accessible, and accurate. Many case studies of real-world applications illustrate this presentation., The text also replaces the language in its historical background and, describes the context in which it is used, both from the application viewpoint, and from that of other speci¯cation standards which use or refer to ASN.1., This book is written by an expert of ASN.1, of its syntax and semantics,, and clearly constitutes a reference on the language. It is intended for those, merely interested in ¯nding a complete and reliable description of the language, and for programmers or experts who may want to look up for the proper usage, of some constructions. The tools available on the website associated with this, book will prove useful to both the pro¯cient and the beginner ASN.1 user., Michel Mauny, Project leader at INRIA, the French National Institute for Research in, Computer Science and Control