Cryptology by Oliver Pell

Cryptology by Oliver Pell

This is an essay I wrote for a mathematics essay prize. We had a number of possible topics to choose from and I choose cryptology, because I already had a passing interest in thanks to my attempts to code encryption algorithms for my computer programs. It won, by the way ;-). This is the original essay with a few corrected spelling mistakes (though there are probably some left). I am currently studying at Imperial College, my home page is here.
Oliver Pell

Contents:
Introduction
Useful Terminology
A Brief History of Cryptography & Cryptanalysis
Early Cryptographic Systems
Cryptography During The Two World Wars
Cryptography In The Modern Age
Cryptography
Single Key Cryptography
Substitution Ciphers
Transposition Ciphers
Product Ciphers
Block Ciphers
Stream Ciphers
Data Encryption Standard (DES)
Public Key Cryptography
The Key Distribution Problem
A Solution To The Key Distribution Problem
Properties For A Two-Key Cryptosystem
Knapsack Problem
Rivest-Shamir-Adleman (RSA) Algorithm
"Real World" Usage Of The RSA Algorithm
Cryptography in the "Real World"
Applications Of Cryptography
Politics Of Cryptography
Cryptanalysis
Types Of Cryptanalysis
Types Of Cryptanalytic Attacks
Frequency Tables
Cryptanalysis Of Public Key Ciphers
A Triumph of Cryptanalysis - Enigma
What Was Enigma?
Initial Work On Cryptanalysing Enigma
What Made It Possible?
The Turing Bombe
The Future
Endnotes
Sources
Authors Notes