An Introduction to Computer Communications

ZX Computing

Bernard Babani R.A. Penfold £2.95 The next book is yet another on computer communications. It used to be fashionable to produce a book on computer games, perhaps now it is just as fashionable to bring out a book on computer communications. The somewhat lengthy title of the book, An Introduction To Computer Communications, may conjure up images of a paperback book as big as the size of a concise dictionary, jammed full of technical information. Well, think again. The book has only 72 pages, and priced at £2.95 is a bit of a let down. Even with the 72 pages, the author has managed to slip in approximately 14 pages of diagrams, of which about only half are necessary. As is the fashion with all these communication books, the initial pages introduce the RS232 and the serial line. Modems are described in general, trying to suggest the best modem to purchase for your computer depending on your requirements. I think that it would be much more useful if the author had perhaps suggested a few modems that the readers may buy depending on their computer rather than yet another diagram of the RS232 port connection. The author states that it can be very useful for the modem to have an auto dial facility so that a great deal of time is not lost repeatedly dialling the host computer telephone number. The author says that it 'seems to take half a dozen or so attempts before most systems can be accessed'. Did he know that it is BT regulations for a number to be re-tried up to a maximum of five times only? After the modem chapter (there are, incidentally, only three chapters in the book), there is a chapter on local networks. This provides options on creating Home-Spun networks, whereby computers can talk to each other. I felt that not enough time was taken on this chapter as this is most definitely something many readers would like to learn more about. The Spectrum, alas, only features for a small amount of time. The book does provide some handy technical information on connecting computers via the serial interface or parallel interface, and I would suggest that this is the book's strongest point. Due to the range of the subject, it would have been far better if the book concentrated on one aspect rather than jumping between networking, radio communications and modems. There is much to learn about these, and there is no doubt that the author does know his stuff, but the book does not do justice either to the author or his chosen topics.