The IT Stuff

Active Directory also known as  NTDS (NT Directory Service) in older Microsoft documents is a hierarchical collection of network resources that can contain users, computers, printers, and other Active Directories. Active Directory Services (ADS) allow administrators to handle and maintain all network resources from a single location.These basic building blocks of Active Directory include

• Trusts
• Forests
• Domains
• Organizational units
• Domain controllers
• Groups
• Sites
• Replication
• Global catalog.

The forest, tree, and domain are the logical parts in an AD network.

The forest is a collection of every object, its attributes, and rules (attribute syntax) in the AD.A tree is a collection of one or more domains and domain trees.The domain is the basic building block of an Active Directory system.Domains are identified by their DNS name structure, the namespace.

The domain is the administrative, security, and replication boundary. As the administrative and security boundary, all permissions (such as object or attribute rights) flow down only to objects within the domain and never to other domains. As the replication boundary, the entire domain is replicated to all other domain controllers for the domain.

The objects held within a domain can be grouped into containers called Organizational Units (OUs).

• Organizational Units (OUs) are used to create a hierarchy within a domain.
• OUs allow grouping of domain objects around a common task, such as a department, division, or projects.
• OUs use to  simplify management by applying rights at higher level OUs which then flow down to subordinate objects.

Physically the Active Directory information is held on one or more equal peer domain controllers (DCs), replacing the NT PDC/BDC model.The AD database is split into different stores or partitions.

A Site object in Active Directory represents a physical geographic location that hosts networks.