Mathematics in Cybersecurity

13What Is Cryptography?

13.1 What Is Cryptography?

Cryptography is a fundamental concept in the field of cybersecurity, with applications spanning various domains, including computer science, information security, and communication systems.

13.1.1 Definition and Purpose

Cryptography is the study and practice of techniques for secure communication in the presence of adversaries. The primary goal of cryptography is to enable two or more parties to communicate sensitive information over an insecure channel, such as the internet, without unauthorized entities being able to intercept, understand, or tamper with the transmitted data.

It is impractical to suppose communications can be completely secure. Numerous obstacles exist to prevent this: treachery, technical limitations, superior technology in possession of the opposition, and others. Encryption (the disguise of sensitive information) is paramount to the transmission of information in such a manner as to make communication as secure as possible.

The process of transforming native information (data “in the clear”) into coded information is called “encryption.” The inverse of this process, the transformation of coded information into native information, is called “decryption.”

The core principles of cryptography revolve around the following key concepts:

1. Confidentiality: Ensuring that the information remains private and accessible only to authorized parties.
2. Integrity: Protecting the data from unauthorized modification or tampering. ...