What is Active Directory?

Active Directory (AD) is a cornerstone component within Microsoft’s Windows server architecture, and an essential cog in the IT environment. But what is Active Directory precisely and how does it work?

Active Directory is a directory service developed by Microsoft for Windows domain networks. It is involved in various tasks, such as managing permissions and user access to networked resources. Notably, it provides IT admins with tools to organize components of a network, such as users, computers, and printers, into a hierarchical roadmap.

Another way to consider the Active Directory is like a phone book of your company containing the comprehensive details necessary for efficient network management.

By using AD, administrators can synchronize changes throughout the network, implement policies on devices, and manage user activities — all from one central location. AD uses Lightweight Direct Access Protocol (LDAP) versions to facilitate communication between users and domains in fluid semantics for humans and software alike.

Embracing AD in your organization allows you to create structure amid complex networks while facilitating enhanced security protocol enforcement across distributed systems. This makes Active Directory a key tool to achieving holistic operational efficiency.

Microsoft is the clear leader in the area of Active Directories. Azure Active Directory is the most popular choice in the Identity And Access Management category, with over 24% of Active Directory market share. Microsoft Active Directory comes in second with over 22% market share.

What are the benefits of Active Directory?

If you’re wondering why your organization should adopt an Active Directory, the answer lies in its numerous advantages for IT management and operations. Let’s take a look at the key Active Directory benefits:

Centralized management: Active Directory provides a single point from which administrators can manage and control network resources. Adopting AD simplifies cumbersome tasks, making your IT organization more scalable. As your business grows, you can add or remove users within your network as needed without undue complexity.

Improved security: Active Directory incorporates robust access control features coupled with effective audit functionality, enabling organizations to enhance their defense against external and internal threats.

Interoperability: Active Directory allows seamless interoperability with other directories, providing administrators with leeway to communicate and share information across different platforms. This enables a far higher level of vendor independence, and can also help to ease pain points that are hampering the cohesion of the operating system.

Granular control: Active Directory enables access control at higher granularity than ever before. It allows admins to define permissions, not just at overall system level but down to individual objects, significantly increasing operational flexibility.

While these Active Directory benefits may vary based on organizational needs and priorities, they each contribute to creating an IT environment characterized by enhanced efficiency, streamlined operations, and improved security. All of these are crucial components for business success in a digital-first world.

How does Active Directory work?

To understand how Active Directory works, you first need to consider its fundamental goal: seamless organization and management of network resources. The mechanism that drives AD consists of a wide range of components working in tandem towards that goal.

Here is a brief overview of what Active Directory looks like in action:

  • The AD system maintains order within organizations’ complex networks by structuring them into different levels — namely domains, trees, and forests. These scalable units make it possible for resources to be efficiently categorized and utilized.
  • The Active Directory’s database stores all critical details about users and resources while ensuring data security through advanced encryption protocols.
  • When users log into a network, Active Directory verifies their identity by checking their entered credentials against stored data. This approach not only authenticates user access but also stipulates what each individual can do on the system according to their assigned roles and permissions.

In essence, Active Directory is the backbone of network management, with four primary and critical functions:

  1. Authentication: Verifying user identities.
  2. Authorization: Defining user capabilities within the system based on assigned roles.
  3. Data storage: Maintaining records about all entities present in the directory.
  4. Administration and management: Centralized control over systems, software distribution, and policy definition, among others.

All of these strands are woven together in the hierarchical structure of the Active Directory, creating an integrated ecosystem that facilitates seamless IT management across the organization.

How is Active Directory structured?

Although organized in a tree-like, hierarchical structure, the Active Directory is not rigid. Rather, it’s flexible and can align with the unique needs of each organization. Even so, there are common, interrelated elements that every AD infrastructure will include, each serving specific purposes. These are:


At the base level, we find domains. These are the security boundaries for objects such as users, computers, and groups. Domains allow organizations to establish consistent policies, and control who has access to what information.


Trees lie at a level above domains, and constitute an assembly of one or multiple domains sharing a contiguous namespace.


The highest-level component is the forest: a collective of one or more trees that share schemas, catalogs, and configuration details, but do not necessarily follow the same naming conventions.

Looking at this layout might bring to mind an actual tree turned upside down — the roots high up forming a wide-ranging canopy (the forest), spreading out into various branches (trees), and further categorizing into smaller subsidiaries as you go lower towards multiple leaves (domains).

This structured approach supports organized data handling with the option for scalability as per organization-specific requirements. Now, when you are asked, “how is Active Directory structured?”, remember the inverted tree! There’s much more intricacy involved than described here, but this primer should give you a foundation about Active Directory’s structural nuances.

What’s in the Active Directory database?

The Active Directory database contains an enormous amount of information, all of which is vital to network management. Here’s what you will find in the AD database:

User account details: These include not only usernames and passwords but extended attributes, like email addresses and phone numbers. Such comprehensive data allows for precision in controlling access to resources based on individual profiles.

Computer account data: From machine names to operating system specifics, exhaustive and detailed information of every computer linked to the network is stored within the Active Directory database.

Group policies: These are another critical component of the data-rich AD. It includes a mix of security parameters and user permissions settings that govern user interactions with systems or applications under your domain’s purview.

Domain Name System (DNS): DNS entries are stored in the Active Directory database, and are crucial for resolving human-readable domain names into corresponding IP addresses. 

Replication metadata: The AD database dynamically registers changes (ie. individuals joining or leaving the network, password modifications, alterations to group policies, etc) into log files via a process known as “replication metadata”. 

Subnets and site links: These assorted ‘pieces’ also find their place inside the AD, contributing to smooth organizational operation.

Active Directory services

The Active Directory comprises a suite of services that work together to manage networks in a centralized manner. In this section, we’ll explain five different types of AD services.

Domain Services

Domain Services (DS) are often regarded as the core component of AD. This service stores information about all network resources across domains and offers methods for other applications on the network to gain access to this data.

Features include:

  • Centralized management of entire directories
  • Ability to scale up or down based on business needs
  • Streamlined sign-on processes for end-users

Lightweight Directory Services

Lightweight Directory Services (LDS) is an Active Directory component that allows directory service instances to run on an operating system without needing domain controllers. It is particularly suitable in application scenarios where no Windows security checks or hierarchy systems are required. LDS is nimble and efficient while maintaining much of its dominant counterpart’s functionality.

Certificate Services

In an Active Directory, Certificate Services help to create, distribute, and manage secure certificates within a public key infrastructure.

Some typical applications for Certificate Services might include:

  • Data encryption at various levels
  • Enhancing email security measures
  • Authenticating web servers

Federation Services

Federation Services enable seamless sharing of identity information between trusted businesses (or “federated” partners). With the help of Federation Services, external users can use their existing credentials for safe access authorization, thereby simplifying processes such as single sign-on (SSO).

Rights Management Services

The Active Directory component known as Rights Management Services controls who has permissions to IT environments. It provides a practical mechanism for protecting data, including restricting access to specific documents or folders, and limiting certain actions (ie. preventing copying or forwarding sensitive emails).

Domains vs. workgroups

When discussing Active Directory, the question of domains vs workgroups comes up not infrequently. Let’s explore why they are different.

Especially when discussing Active Directory networks, a domain can be thought of as a centralized system for managing multiple devices and users within an organization. All resources are interconnected on this infrastructure.

On the other hand, a workgroup represents a decentralized model where each device operates independently. Each user or computer has its set of controls without any overarching system to unify them.

For instance:

  • Within a domain, users need only a single set of credentials to access shared resources. Changes made by administrators to policies or permissions automatically ripple throughout the network due to the centralized nature of the Active Directory.
  • In contrast, for workgroups, each device necessitates individual setup and management. Workgroups serve well for small environments with few interconnected systems because they lack the convenient centralized control provided by AD domains.

Domain vs Workgroups have their uses and benefits, depending on specific IT conditions and requirements. To choose the right option for your organization, you will need to weigh factors such as operational scale, resource availability (both human and technical), cybersecurity needs, and future growth plans.

Why AD management and security is important?

Managing the Active Directory isn’t merely an administrative task. It’s a key part of the IT security puzzle, guarding against cyber threats while ensuring the business functions smoothly.

To begin with, the entire access mechanism in an IT organization revolves around the identity of its users stored in AD. Keeping track of user identities — who has access to specific resources and data — also falls into the purview of Active Directory management tasks.

Secondly, poorly maintained Active Directories can be breeding grounds for security vulnerabilities. Mismanaged user rights — excessive privileges or outdated accounts — pose significant risks. These instances could act as open doors for potential hackers.

Unregulated directories also heighten susceptibility to insider attacks. For example, disgruntled employees with unwarranted, over-privileged access might exploit their position for unethical gains while being virtually untraceable.

Finally, yet equally important, AD management helps to ensure compliance with legal regulations such as GDPR or HIPAA. Strict adherence to these guidelines demands certain controls, without which the business will face steep fines and reputational harm.

Active Directories: Atera to the rescue

Implementing and managing Active Directory (AD) effectively is no small feat. Yet it’s vitally important for ensuring that your enterprise remains secure, organized, and efficient. This is where Atera can help.

Atera simplifies the management of AD while also enhancing its security. The platform provides AI-powered solutions that are ideal for businesses seeking to minimize manual labor without compromising on control or safety.

Here are a few ways in which Atera’s all-in-one IT management platform helps businesses manage their directories too:

  • Advanced monitoring: With detailed insights into every modification in the directory environment, carrying out regular audits becomes a breeze.
  • Active automation: Gone are days of tedious manual work. Atera’s automation capabilities do much of the heavy lifting for Active Directories behind the scenes.
  • Smooth management: You’ll handle user roles, access permissions, and resource allocation with ease to establish optimal workflows in your organization.
  • Crucial alerts: Be notified instantly about unaccounted changes that may indicate hacking attempts.

Integrating Atera into your existing IT infrastructure will help you achieve higher productivity levels in Active Directory management, and marked improvements in organizational efficiency. Start your free Atera trial today.

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