CHAPTER 1

Cryptography – The Basics

Introduction

When communicating, the confidentiality of messages needs to be ensured

so that no one other than the intended recipient of the message can receive

the message content. Cryptography introduces this security and secrecy in

message communication as also in the information by concealing their

contents.

Cryptography disguises the message/ information and hides its contents. The

annotation given to an encrypted message by encryption is ciphertext, and

the process by which this ciphertext is converted back into plain text is

decryption.

It is important to be an indispensable tool for protecting information in

computer systems, used for encryption and decryption of data it is vital to

communication today.

A specific set of skills are required to create layered algorithms and

mathematical problems, including analytical skills, technical abilities, and

effective communication.

Cryptography professionals need to have a strong understanding of

mathematical principles, such as linear algebra, number theory, and

combinatorics. Professionals apply these principles when they are designing

and deciphering strong encryption systems. Basic knowledge of computer

science and a secondary level of mathematics knowledge are the pre-

requisites.

Structure

In this chapter, the following topics will be covered:

Introducing cryptography

Strength of cryptography