Cryptography: The Key to Digital Security, How It Works, and Why It Matters

Martin (Everyday Cryptography), an information security scholar, provides a useful introduction to cryptography, successfully showing the field isn’t one “only computer whiz kids have any hope of understanding.” Underlining cryptography’s importance, he observes that digital encryption “underpins everyone’s security in cyberspace,” from online shopping to keyless car entry. Starting at the most basic level of computer science, Martin explains how binary code works, before moving to more advanced topics such as symmetric encryption and hash functions. He shows a knack for communicating demanding ideas, breaking up the text into short chunks, echoing the structure of block cipher and with the same result of facilitating quick deciphering of sometime complex information. He also deploys physical metaphors for the abstract cryptographic tools he covers, describing asymmetric encryption, for instance, as a series of padlocks attached to a briefcase, and the challenge-response principle as a blind boomerang hunter. For historical context, Martin connects today’s encryption techniques to codes used by the likes of Julius Caesar and Mary, Queen of Scots. At the close, he discusses the difficult balancing act between security and personal privacy, and likely future developments in the cryptographic field. This timely book will leave digital neophytes significantly better informed about a vital area in computer science. (May)