Access Control List (ACL)
An Access Control List (ACL) is a security mechanism that specifies which users or system processes are granted access to objects, as well as what operations are allowed on given objects. It is commonly used in operating systems, network devices, and applications to enforce permissions and restrict unauthorized access to resources like files, directories, or network traffic. ACLs provide fine-grained control by listing permissions for individual users or groups, enhancing security and data protection.
Developers should learn ACL configuration to implement robust security in systems and applications, especially when managing multi-user environments or sensitive data. It is essential for use cases such as file system permissions in Unix/Linux (e.g., using commands like `setfacl`), network security in routers and firewalls to filter traffic, and application-level access control in web services or databases. Understanding ACLs helps prevent unauthorized access, comply with security policies, and design scalable permission systems.