What's the best encryption algorithm for the iPhone in terms of speed and security?

Question

The iPhone supports the following encryption algorithms

enum {
    kCCAlgorithmAES128 = 0,
    kCCAlgorithmDES,            
    kCCAlgorithm3DES,           
         


        

Answer 1

RC4 is probably the fastest, but it has some security issues. If security is an important factor, I would recommend going for AES128. AES is the standard solution and on the top of excellent security you might expect the implementations to get faster over time as people are still actively working on them. Maybe future CPUs will also include support for it, just like new Intel desktop processors will.