What do Pluggable Authentication Modules (PAM) provide?

Pluggable Authentication Modules (PAM) provide libraries for authentication in Linux and UNIX-like operating systems. They are designed to separate the authentication process from the application that requires authentication, allowing for greater flexibility and ease of configuration. By using PAM, system administrators can implement different authentication methods, such as password authentication, multi-factor authentication, or integration with external authentication services, without modifying the applications that use PAM.

The modular nature of PAM allows applications to choose which methods to use and enables the addition or removal of authentication mechanisms as needed. This is particularly beneficial for managing various security policies across a system and facilitates easier updates to authentication methods without disrupting existing applications. PAM's architecture ensures that changes can be made centrally, affecting all applications configured to use PAM, while individual applications remain unaware of these changes.

Therefore, the role of PAM is crucial in enhancing security and managing user authentication effectively across a wide range of applications and services.