This is a set of lecture notes for a summer course on cryptography, taught by the authors at the Massachusetts Institute of Technology (MIT).

Contents: Introduction; Block ciphers; Pseudorandom functions; Symmetric encryption; Hash functions;Message authentication; Computational number theory; Number-theoretic primitives; Asymmetric encry . . . . .

In this tutorial, selected topics of cryptology and of computational complexity theory are presented. We give a brief overview of the history and the foundations of classical cryptography, and then mo . . . . .

These notes are a brief introduction to the RSA algorithm and modular arithmetic. They are intended for an undergraduate audience.

Lectures on classical and quantum cryptography. Contents: Private key cryptosystems. Elements of number theory. Public key cryptography and RSA cryptosystem. Shannon`s entropy and mutual information. . . . . .