دانلود کتاب رمزنگاری کلید مخفی – رمزها، از ساده تا نشکن

There are several threads that led to the writing of this book. Let’s begin with my high school friend Charlie Rose. Charlie worked in the school bookstore. One day, while ordering books for the store, he noticed the book Cryptanalysis by Helen F. Gaines. Charlie wanted the book, and he also wanted the employee discount. But there was a hitch. The minimum order the store could place was three copies. Charlie needed to get two other people to buy the book. He promised that we would all read the book together, then make up cryptograms that the others would solve. I bought the book, read it, and made up cryptograms, but Charlie had lost interest.