Public Key Cryptography

Abstract

As we have seen, a cryptosystem is a system of the form

$$\displaystyle \langle {\mathcal M},{\mathcal C},e,d,{\mathcal K}_e,{\mathcal K}_d\rangle , $$

where ${\mathcal M}$ is the message space, ${\mathcal C}$ is the space of all possible cryptograms, e is the encryption transformation, d is the decryption transformation, ${\mathcal K}_e$ is the encryption keyspace, and ${\mathcal K}_d$ is the decryption keyspace.