eldavojohn writes "A method of computing from a 2009 paper allows the computing of data without ever decrypting it. With cloud computing on the rise, this may be the holy grail of keeping private data private in the cloud. It's called Fully Homomorphic Encryption, and if you've got the computer science/mathematics chops you can read the thesis (PDF). After reworking it and simplifying it, researchers have moved it away from being true, fully homomorphic encryption, but it is now a little closer to being ready for cloud usage. The problem is that the more operations performed on your encrypted data, the more likely it has become 'dirty' or corrupted. To combat this, Gentry developed a way to periodically clean the data by making it self-correcting. The article notes that although this isn't prepared for use in reliable systems, it is a quick jump to implementation just one year after the paper was published — earlier encryption papers would take as much as half a decade until they were implemented at all."