In a textbook for a course in applied algebra for junior or senior students of mathematics or computer science, Hardy (Colorado State U.) Fred Richman (Florida Atlantic U.) and Carol L. Walker (New Mexico State U.) describe the mathematics of data communication and storage, and offer advice on using some popular software packages to do complication calculations and make mathematical ideas more accessible. Their central concerns are data security and integrity, that is making data visible only to friendly eyes, and minimizing data corruption. The tools they use come primarily from number theory and the theory of finite fields; they develop the mathematics as needed, but they have found that students with a background in abstract or linear algebra can find footing there. No date is noted for the first edition. Annotation ©2009 Book News, Inc., Portland, OR (booknews.com)