The README has lots of really cool words and names and things. But it doesn't say what homomorphic encryption is or what it is good for. Could someone enlighten me?
TL;DR: It allows you to edit encrypted stuff without decrypting it.
For example, if you had a book of everyone's salaries, you can ask Bob to add $5000 to it. Normally you'd have to give him the key, but with homomorphic encryption you can just perform operations without decrypting it and having Bob know everyone's salaries.
This becomes really powerful for stuff that you need to work with lots of data without knowing the contents of - cloud computing, for example.
"Homomorphic encryption is a form of encryption which allows specific types of computations to be carried out on ciphertext and obtain an encrypted result which decrypted matches the result of operations performed on the plaintext. For instance, one person could add two encrypted numbers and then another person could decrypt the result, without either of them being able to find the value of the individual numbers."
For a recent project, I'd be interested in searching and sorting of encrypted data; I wonder if this is up to that. The tricky bit with search is that in many cases, you want to be able to search for substrings, not just an exact match.
A worthwhile example is the problem of encrypted spam. In theory, spammers could use public keys to evade spam filters, and systems like PGP and S/MIME do not give you any ability to prevent that. On the other hand, an FHE system would allow Google to perform spam filtering on your encrypted email, and so that you receive both the email itself and an encrypted "spam or not spam" bit from Google. You can imagine this sort of thing be applied in other situations -- advertising, options modeling on EC2, etc.
Unfortunately, FHE is nowhere near practical enough to do that sort of thing. Maybe in a decade or two we will see FHE implementations used outside the research community.
Since when is making inoffensive jokes considered trolling? I was amused by the similarity between the words 'homomorphic' and 'homeopathic' so I thought other people might be too.
The number of downvotes my attempt at humour received would suggest that I was wrong.
