{"id":862,"date":"2011-04-13T13:07:56","date_gmt":"2011-04-13T17:07:56","guid":{"rendered":"http:\/\/antipaucity.com\/?p=862"},"modified":"2011-04-13T13:07:56","modified_gmt":"2011-04-13T17:07:56","slug":"applied-cryptography-2d-ed-by-bruce-schneier","status":"publish","type":"post","link":"https:\/\/merikebi.warrenmyers.com\/?p=862","title":{"rendered":"applied cryptography, 2d ed by bruce schneier"},"content":{"rendered":"

As recently promised<\/a>, here is my review of {{Bruce Schneier}}’s seminal work, {{Applied Cryptography}} (2d edition).<\/p>\n

I received my now-signed copy of Applied Cryptography (2d ed) for my 16th birthday – about a year after it was published.<\/p>\n

Of all the “odd” books I asked-for when I was younger, this single volume had to take the cake for being both the most expensive, and the least-likely-to-be-read of any.<\/p>\n

Bruce Schneier is a world-renowned cryptographer, researcher, and generally Smart Guy\u2122. He has written several other books (many of which I have read ({{Beyond Fear}}, {{Practical Cryptography}}, {{Secrets and Lies}}), and several I own). I also follow on an intermittent basis his blog: schneier.com<\/a>.<\/p>\n

A warning before I go any further – since this book has not been updated in 15+ years, many of the technologies outlined now look incredibly dated or quaint (a 100Mhz processor being “top of the line”, for example). Likewise, measuring computational feasibilities in MIPS-years seems bizarre to me… then again, I’ve never used a MIPS processor.<\/p>\n

Back to the book. A lot of time and space is spent on the mathematics and theory behind crypto systems: which is quite cool… except when you don’t understand any of it (as I didn’t a dozen+ years ago [and still don’t to some extent now]). Protocols for a variety of “interesting” activities are discussed: key exchange, digital cash, contract signing, digital signatures, etc.<\/p>\n

The most interesting part of the book is the appendix containing C code for several of the algorithms in the book.<\/p>\n

Schneier’s writing mixes the highly technical with the amusing (eg p157):<\/p>\n

Another biological approach is to use genetically engineered cryptanalytic algae that are capable of performing brute-force attacks against cryptographic algorithms. These organisms would make it possible to construct a distributed machine with more processors because they could cover a larger area. The plaintext\/ciphertext pair could be broadcast by satellite. If an organism found the result, it could induce the nearby cells to change color to communicate the solution back to the satellite.<\/p>\n

Assume the typical algae cell is the size of a cube 10 microns on a side (this is probably a large estimate), then 1015<\/sup> of them can fill a cubic meter. Pump them into the ocean and cover 200 square miles (518 square kilometers) of water to a meter deep (you figure out how to do it – I’m just the idea man).<\/p><\/blockquote>\n

In the intervening time, AES<\/a> has been adopted as a national standard, replacing DES<\/a>. We all rely on encryption in daily life on the web (https<\/a>) when banking,\u00a0making\u00a0purchases, or even reading our facebook and twitter accounts. Cryptography has become\u00a0ubiquitous\u00a0and invisible to most of us. The product I work most heavily with relies on certificate-based https for all of its internal communication.<\/p>\n

In my opinion, this book is still of immense value – though in a different way than it was in the mid 90s: now it’s to serve as a warning about relying on technology and not considering the source, rather than upon how to implement and promulgate that technology.<\/p>\n