Microsoft Active Directory is a centralized directory service that stores and organizes information about network objects such as users, groups, and computers in a hierarchical database accessible via LDAP. It provides authentication and authorization services, primarily using the Kerberos protocol, to control access to network resources and enable single sign-on for domain-joined machines. The service allows for the central management and enforcement of security policies, user settings, and software configurations through Group Policy, and it supports a multi-master replication model to ensure redundancy and availability across multiple servers known as domain controllers. Its structure includes domains, trees, and forests, with trust relationships to allow resource sharing, and it uses a flexible schema to define and store object attributes.
