BKTSDET.RVW 940712 SAMS Publishing 11711 N. College Ave., Suite 140 Carmel, IN 46032-5634 317-573-2500 317-581-3535 800-428-5331 800-428-3804 hayden@hayden.com haydenbks@aol.com 76350.3014@compuserve.com "Top Secret Data Encryption Techniques", Held, 1993, 0-672-30293-4, U$24.95/C$31.95 This book is a lot of fun, and may even be of some use. A number of ciphering techniques are outlined, and the interested hobbyist can undoubtedly come up with many variations on the themes. The included source code, in BASIC, is simple and straightforward, and can easily be modified to suit new ideas. Fun, and possibly useful, but definitely *not* top secret. Of the five chapters that actually deal with encipherment, three deal strictly with mono- alphabetic substitution. Regardless of how complex the substitution, a one-to- one correspondence is susceptible to either character frequency analysis or brute force cracking. The remaining two chapters deal with poly-alphabetic substitutions that are still, because of the fact of substitution, subject to brute force attacks. (The one exception is the generation of a "one time" pad.) Advanced encryption is currently the province of higher mathematics. Explanations and sample code for these would require more sophistication than the current book demands. Still, it would not have been impossible to include them, and it might have improved the scope of the book. Simple, and subject to attack, or not, the techniques in the book can be used for some measure of privacy and security. As stated in the preface, even crackable codes may raise the expense of getting at the data beyond its worth. rot13 this message after reading. copyright Robert M. Slade, 1994 BKTSDET.RVW 940712 ====================== DECUS Canada Communications, Desktop, Education and Security group newsletters Editor and/or reviewer ROBERTS@decus.ca, RSlade@sfu.ca, Rob Slade at 1:153/733 Author "Robert Slade's Guide to Computer Viruses" (Oct. '94) Springer-Verlag