December 2025
Intermediate to advanced
704 pages
19h 14m
English
Content preview from Ubuntu Linux Bible, 11th Edition
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CHAPTER 24Understanding Advanced Linux Security
Due to ever-changing and growing threats, implementing basic computer security is no longer enough. As malicious users gain access to and knowledge of advanced tools, so must a Linux system administrator. Understanding advanced computer security topics and tools must be part of your preparation.
In this chapter, you will learn about cryptography basics, such as ciphers and encryption. You will also learn how authselect profiles and Pluggable Authentication Modules (PAM) can be used to safely manage Linux system authentication features.
Implementing Linux Security with Cryptography
Using cryptography enhances the security of your Linux system and its network communications. Cryptography is the science of concealing information. It has a long and rich history that goes back far before computers were around. Because of its heavy use of mathematical algorithms, cryptography has easily transitioned to computers. Linux comes with many cryptographic tools ready for you to use.
To understand cryptographic concepts and the various Linux tools, you should know a few cryptography terms:
- Plain text: Text that a human or machine can read and comprehend
- Ciphertext: Text that a human or machine cannot read and comprehend
- Encryption: ...
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