Encrypted computing: Speed, security and provable obfuscation against insiders

Over the past few years we have articulated theory that describes `encrypted computing', in which data remains in encrypted form while being worked on inside a processor, by virtue of a modified arithmetic. The last two years have seen research and development on a standards-compliant processor that shows that near-conventional speeds are attainable via this approach. Benchmark performance with the US AES-128 flagship encryption and a 1GHz clock is now equivalent to a 433MHz classic Pentium, and most block encryptions fit in AES's place. This summary article details how user data is protected by a system based on the processor from being read or interfered with by the computer operator, for those computing paradigms that entail trust in data-oriented computation in remote locations where it may be accessible to powerful and dishonest insiders. We combine: (i) the processor that runs encrypted; (ii) a slightly modified conventional machine code instruction set architecture with which security is achievable; (iii) an `obfuscating' compiler that takes advantage of its possibilities, forming a three-point system that provably provides cryptographic `semantic security' for user data against the operator and system insiders.