Chapter one examines the need for cryptography, chapters two to five show how encryption is built from symmetric and public keys, how passwords are encrypted, and digital signatures created. Chapters 6 to 8 show how the element of cryptography are used to build infrastructure with digital certificates and protocols. Chapters 9 deals with hardware issues, including devices, such as smart cards, that can function as cryptographic ciphers. Chapter 10 deals with legal issues in a U.S. context that surround digital signatures. Chapters 11 and 12 offer case studies in encryption.
Hackers have a history of breaking into well guarded computers.
A 56 bit key was broken in 24 hours by the Electronic Frontier Foundation. But decoding ciphers written with high level algorithms based on a 90 bit key would take 535 years to unravel and a cipher written with a 128 bit key would take 146 billion millennia, say the authors. Today, U.S. government export standards limit the key size of certain data products. Even at mid-range key sizes, messages are secure, suggest the authors. RSA Security's Official Guide to Cryptography is readable, thorough and even charming.