Browse
Directory Services (LDAP, Active Directory)
The centralized store of identities, groups, and attributes that most enterprise authentication and authorization builds on.
What it is
A directory service is a centralized, hierarchical store of identities, groups, and attributes — the foundational identity data store that authentication systems, applications, and access-control policies are built against.
Key points
- LDAP: the underlying protocol for querying and modifying directory data — still widely used, especially by legacy and on-prem enterprise applications.
- Active Directory: Microsoft's directory service implementation, combining LDAP with Kerberos authentication and Group Policy — the dominant directory in traditional enterprise (Windows-centric) environments.
- Cloud-native directories: modern cloud identity providers largely replace on-prem directories for cloud-first organizations, though many enterprises still run hybrid setups syncing on-prem AD with a cloud identity provider.
- Groups as the unit of access management: assigning permissions to directory groups (not individual users) and managing group membership is what makes access administration tractable at organizational scale.