The book Computers in Communication by Gordon Brebner was originallypublished by McGraw-Hill International (UK) Limited in 1997. This edition hasbeen made available in electronic PDF form by the author, following the originalversion going out of print and the copyright reverting to the author. All identifedtypographical errors in the original edition have been corrected, butotherwisethere has been no updating of the content. Inparticular, all page numbering is thesame as in the original version..