Ref: [here]

Homomorphic Encryption With ElGamal: Multiply/Divide

--

There are some encryption methods which allow us to process encrypted values. In this way we can process using certain mathematical operations on cipher values, and end up with the result when we decrypt. For example, if we encrypt a value of 4 and a value of 3 with a public key we get:

Epub(4), Epub(3)

--

--

Prof Bill Buchanan OBE FRSE
ASecuritySite: When Bob Met Alice

Professor of Cryptography. Serial innovator. Believer in fairness, justice & freedom. Based in Edinburgh. Old World Breaker. New World Creator. Building trust.