Practical applications of homomorphic encryption algorithms?

Question

It appears there there were interesting things going on in cryptography: the first homomorphic encryption scheme appeared recently (explanation, HT). Roughly sp

Answer 1

Here's a wild shot in the dark:

We're thinking about protecting the plaintext from the person doing the computation on it. But what if the objective was to protect both the plaintext AND the algorithm?

Take, for example, MRI machines. The most expensive part of the MRI machine is the algorithm in which the machine analyzes the magnetic resonance data. Because of this, they are heavily protected by hardware devices designed to destroy the program before allowing itself to be examined by an untrusted party (or anyone for that matter).

If an MRI maker could centralize MRI data computing, it would be a fantastic reduction in risk of losing their algorithm. However, laws prevent them from accessing private patient data.

So! Homomorphic encryption allows this to happen where the patient data and the algorithm are both protected. The 'fully' homomorphic encryption (i.e. inducing a ring homomorphism onto the encrypted data) allows for a much more efficient and robust set of computations to operate on the data.