Symmetric Cryptography in Javascript

The authors take a systematic approach to developing a symmetric cryptography library in Javascript. They study various strategies for optimizing the code for the Javascript interpreter, and observe that traditional crypto optimization techniques do not apply when implemented in Javascript. They propose a number of optimizations that reduce both running time and code size. The optimized library is about four times faster and 12% smaller than the fastest and smallest existing symmetric Javascript encryption libraries. On Internet Explorer 8, the library is about 11 times faster than the fastest previously existing code.