Standards for Open Systems Interconnection

~ Standards for Open Systems Interconnection T Knowles, J Larmouth and K G Knightson Blackwell Scientific Ltd., UK (1987) £30, 392 pp, ISBN 0632 0•8682 Open Systems Interconnection (OSI) has acquired a lot of momentum in recent years. The' literature on the subject has, perhaps, acquired most of the speed, but has often lacked the required weight. Part of this deficiency is remedied here by giving an account of a number of the most important international standards which are central to OSI. It will serve many of the needs of system designers and consultants who may be familiar in outline with OSI, but need fairly rigorous introduction to the standards and the principles behind them - - perhaps as a preliminary to doing battle with the standards themselves. The book is not an elementary introduction to OSI. An initial knowledge of OSI itself, together with a general understanding of the principles of computer communications, especially at the software level, are essential prerequisites for the reader. The general principles of OSI are thoroughly covered - - establishing a base for the major content of the book, which is a description of the protocols and services defined by the International Standards Organisation (ISO). The emphasis is on the upper layers of OSI, although there is a useful discussion of the lower layers, particularly the relationships between link level (level two) and network level (level three) standards in both local area networks (LANs) and wide area networks (WANs). File Transfer Access and Management (FTAM), Job Transfer and Manipulation (JTM), and virtual terminal standards are all discussed in detail, although the emphasis is towards JTM and FTAM. The underlying application layer elements are well covered, and there is an especially useful description of the concurrency commitment, and recovery facilities needed both by such as distributed transaction

vol 11 no 6 december 1988

processing and databases. The issues of OSI management, security and conformance testing are lightly but usefully treated. The X.400 message handling service and some other CCITTdefined standards, such as ISDN, are not covered. Relations between CCITT and ISO seem to be improving, and these standards are already roughly OSI-based. Given their importance, and the probability that they will be absorbed - - into the OSI standard-set, their omission is unfortunate - - however, the book is

m already nearly 400 pages long, and can perhaps be forgiven for adopting a strict definition of what is inside the OSI set. The book is written in a clear, lively, and enthusiastic style, and is a useful and cost-effective addition to any library of computer communications books. I shall certainly be recommending it for my own company library. Finally, this book is likely to act as both a text book and a work of reference. The relatively small index and total absence of a glossary are therefore significant deficiencies. OSI is moving rapidly, and a new edition will probably be justified within ayear or t w o - - p e r h a p s this will be an opportunity for these items to be added. John I Davies Data Logic Ltd UK

Computer architecture and communications Neil Willis John Wiley & Sons Ltd., UK (1986) £13.20, 275 pp, ISBN 0830 28703 This book presents a basic description of computer architecture and elementary data communications suitable for students at a technical institute, for those requiring an introductory service course in computing hardware, or for programmers and operators who only require knowledge of very basic concepts. It is highly hardwareoriented, being simple, clear and concise in its descriptions. Providing readers are only looking for basic hardware concepts they should not be disappointed. However, by covering files in four pages, paging in three pages, X.25 in four pages and the entire field of local and wide area network architecture and protocols in only four short chapters, readers may become frustrated by the lack of technical depth. The book begins with a very elementary introduction to the basic computer components, followed by a chapter on digital logic and integrated circuits. The next eight

chapters cover the usual principles of a basic hardware system-peripherals, files, storage media, coding systems, machine codes, CPU, interrupts and I/O handling. Rather surprisingly, the book finishes with four chapters on data communications and networks. This topic really justifies a separate textbook in its own right, rather than being added on as a hardware extension to the earlier description of computer architecture. This would have allowed coverage of the architecture topics in more depth. Most of the chapters contain a problem section (without solutions) which is useful for class exercises. The book does meet the authors' aims outlined in the introduction. This paperback is good value as an introduction to computer architecture and data communications. Ray Hunt University of Canterbury New Zealand

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