A directory in non-technical terms is a hierarchical structure that stores data and objects found within a computer network. An Active Directory is an organizational structure comprising user accounts for authentication, addresses, security groups, group policies, file shares, and physical resources such computers and printers.
All users in an Active Directory must be given permission to access all this information upon request. In this article, we’ll dive deeper and have a glance at what makes up AD Domain services.
Features of an Active Directory
An Active Directory is implemented by building structures that store data based on the logical and hierarchical organization of information. The data stored in the directory has all the information about the Active Directory objects such as network printers, servers, shared volumes, and individual computer accounts.
The basic element of security that is integrated into an Active Directory is implementation of log-on authentication and access controls. Only system administration can use a single network log-on to manage the entire directory and organization in the network.
Active Directory Domain Services uses policy-based administration to make the work of system administrators easier, especially in a more complex network infrastructure. Implementing policy-based authorization revolves around the following settings:
These sets of rules used to define objects and attributes within the Active Directory. Schemas also define the limits of instances and how they are represented in the directory.
- Global Catalog
This catalog has all the information on every object defined in the directory. This enables both users and administrators to locate information even if the data is on a different domain.
- Query and Index Mechanism
Query indexing enables users or applications, locate objects and their properties. They come in handy when looking for specific information in the directory structure.
- Replication Service
This dedicated service distributes data all over the network. The domain controllers help in the replication process by containing a complete copy of all data and directory information stored in the domain. All changes made in the Active Directory Domain Service are usually replicated to all domain controllers in the domain.
- Understanding Active Directory Domain Service
Some of the core concepts within the Active Directory that give a clear understanding of what the Active Directory is are briefly highlighted below:
- Active Directory Structure and Storage Technologies
The Active Directory storage design comprises four features namely:
- The Active Directory, domain, and forests. Domain and other organization units define the Active Directory logical structure.
- Domain Name Systems (DNS) that is responsible for resolving names for the domain controller to help the Active Directory reflect its organization structure.
- A Schema that holds the definitions of all objects stored in the directory.
- Data Store that manages the storage and retrieval of data from the domain controllers.
- Domain Controller Roles
A domain controller is a configured Windows server with an Active Directory service installed. The system administrator has the responsibilities of setting up different roles. Any new server configuration is complete when a specific role is assigned to a domain controller by installing Active Directory Domain Service. Within the Active Directory, there are specialized roles that perform specific functions in an Active Directory environment. Such specialized roles include global catalog servers and operations masters.
- Active Directory Schema
This schema defines the blueprint that describes all rules and objects that are stored in the Active Directory and all the attributed related to that particular object. Therefore, an Active Directory Schema defines the content and structure of objects and the attributes used when creating the object.
- Understanding Trusts
Raising the Domain and Forest functional levels means that no forests and domains running earlier versions of operating systems can be integrated into the new level. For example, using a Windows Server 2016 means that you cannot add domain controller or a forest running Windows Server 2008. Each domain functional level has their corresponding enabled feature that also corresponds to the version of the Windows Server Operating System used.
- Active Directory Replication Technologies
The directory replication model uses mechanisms that enable the Active Directory update capabilities. The domain controllers will track changes received and will only implement the updates that have taken place since the last replication. The update tracker has two roles:
- Changing what has not been received or need to be replicated at the destination.
- Resolving conflicts arising from simultaneous changes to an object.
- Active Directory Search and Publication Technologies
The reason behind having an Active Directory is to enable users, objects, applications, services search, and publish any useful information. Such operations include:
- Searching and comparing data.
- Finding information relating to available service.
The component used by the Active Directory in its search function is the LDAP (Lightweight Directory Access Protocol) while the one responsible for service publication is the Key Distribution Center.
- Understanding Schema
A Schema is an Active Directory service used to define objects and attributes that are used by the directory service to store data. A combination of complex definitions may be used to define objects that need more complexity. New definitions to the schema can be used to define new objects in the Active Directory. A schema is preferably stored in its own partition within the directory and replicated among all existing domain in the forest.
With so many changes that have taken place in the configuration of Active Directory Domain Services, it is important to note that the article defines the general overview of a functioning Active Directory Domain Service and server role.
An Active Directory network infrastructure provides a centralized storage and management of objects. The system administrator through group policies can manage access and availability of resources securely when sharing network resources.
An Active Directory Domain Service acts as a foundation of windows servers identify and provides a central basis for authentication and authorization for all the server roles in a typical Windows Server Operating System.
Some of the distinct features found in the latest Active Directory configurations include system auditing, password, and account lockout policies, read-only domain controllers, the ability to restart domain services, and an Active Directory Database Mounting Tool.