The CIA is not in the habit of discussing its clandestine operations, but the agency’s purpose is clear enough. As then-chief James Woolsey said in a 1994 speech to former intelligence operatives: “What we really exist for is stealing secrets.” Indeed, the agency declined to comment for this article, but over the course of more than 80 interviews, 25 people—including more than a dozen former agency officers—described the workings of a secret CIA unit that employed Groat and specialized in stealing codes, the most guarded secrets of any nation.

The CIA Burglar Who Went Rogue | History & Archaeology | Smithsonian Magazine.

Homomorphic encryption is where one party (Alice) encrypts data and passes it to another (Bob) with an encrypted key. This means that Bob can’t read the data, but can perform computations on it, and pass the encrypted results (which Bob can’t read) to Alice, so that she can decrypt it with her key. This is especially useful in the age of cloud computing, webservices, SaaS and private records.

Alice and Bob in Cipherspace » American Scientist.