Cryptographic Tools and Techniques

This chapter discusses cryptography, which can be defined as the art of protecting information by transforming it into an unreadable format. Cryptography includes methods such as symmetric encryption, asymmetric encryption, hashing, and digital signatures. Each provides specific attributes and solutions. Authentication is another key goal of cryptography. First, authentication is associated with digital signatures. Authentication provides a way to ensure that a message is from whom we believe it's from. In its basic form, authentication is used to determine identity. It is also part of the identification and authentication process. Integrity is another cryptographic goal. Integrity is important while data is in transmission and in storage. Integrity means that information remains unaltered. The designer of a cryptographic system must also understand the implications of cryptographic methods and design. The strength of the encryption process is based in part on the cryptographic key. The cryptographic key, or simply key, is a piece of information that controls how the cryptographic algorithm functions. It can be used to control the transformation of plain text to cipher text or cipher text to plain text.