Enough money and time applied to a long enough message will break almost any enciphering job. If you LEARN ENCRYPTION TECHNIQUES WITH BASIC AND C++ keywords, phrases or pseudorandomly sequenced characters, you should see a longer work week for interceptors. Author Gilbert Held's book locks arms with William R Cheswick's FIREWALLS AND INTERNET SECURITY, Marcus Goncalves' FIREWALLS: A COMPLETE GUIDE, Scott Oaks' JAVA SECURITY, Kaustubh Phaltankar's PRACTICAL GUIDE FOR IMPLEMENTING SECURE INTRANETS AND EXTRANETS, and Bruce Schneier's E-MAIL SECURITY.
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http://rapidshare.com/files/73307271/learn-en.rar