What is a Directory Service?

Directory services have been around for decades and are still used by many companies today for identity and access management. They usually run in the background and are useful for storing rich user profiles, setting granular access controls, and most importantly centralizing authentication.

In this article, we'll cover everything you need to know about directory services, why companies use them, examples of the major directory services, and how they work to manage identities and access.

What is a directory service?

A directory service is a database that stores information about users and resources on a network. It lets you organize people, devices, and applications and manage access to them.

As a directory, it acts like a phone book for the network, listing information on objects such as users, groups, computers, printers, and other resources. Each with corresponding attributes including names, permissions, or addresses, among others. As a service, it provides mechanisms for accessing, querying, and updating this information via standardized protocols like LDAP.

Alongside managing information, directory services also facilitate authentication (verifying user identities) and authorization (determining access rights to resources). Admins use them to onboard new users, manage access privileges, and control access to apps and resources within the company.

Who are the most common directory service providers?

The most common directory service providers include:

• Active Directory: Known for its deep Windows integration with features for user and resource management, authentication, and security within Windows networks.
• Google Workspace Directory, formerly known as G Suite Directory, is a popular pick for businesses using Google's productivity suite.
• Apache Directory Server is an open-source directory service that supports LDAP and is written in Java. It’s ideal for organizations that require a customizable directory service or those integrating directory services into Java apps.
• Red Hat Directory Server (formerly 389 Directory Server): Known for its enterprise-level features, including multi-master replication, high performance, and scalability. It's designed to manage user access to multiple systems in Unix/Linux environments.
• Apple Open Directory: Part of macOS Server, known for its integration with Apple's ecosystem, combining LDAP, Kerberos, and DNS to manage Mac-specific configurations and user policies.
• Okta universal directory, is cloud based and offers directory services as part of its broader identity services. Perfect for cloud-centric organizations, it streamlines identity across various cloud apps.

Why do companies use directory services?

Companies use directory services for several reasons including:

Increased security

Directory services act as gatekeepers, determining who gets in and what they have access to — from files and applications to entire networks. They authenticate users and authorize access based on policies set by the company which helps prevent unauthorized access and protect sensitive data.

Simplified account management

Managing separate accounts and passwords for each employee across systems is a tedious and time-consuming job. Directory services centralize account management, allowing admins to create, disable, and update accounts from one place.

Improved compliance posture

Regulations often require companies to restrict access to certain systems and data. Directory services make it easier to apply access controls consistently across all the apps and resources used within the company, helping companies stay compliant with regulations like HIPAA, GDPR, and PCI DSS.

Directory services also log each instance of resource access including who accessed what, the time they accessed it, which generates an audit trail that’s invaluable for internal audits and regulatory reviews.

Better user experience

With directory services, employees can access the apps and resources they need with single sign-on, meaning they waste less time logging in to each app one by one.  

Plus, it spares them the headache of memorizing multiple authentication factors like passwords or having to make frequent calls to IT for help when they forget their login details.

How do directory services work?

Directory services work through a client-server model, where the server hosts the directory service, and the clients interact with it to perform various operations such as searching, adding, and modifying identities in the directory.

At the heart of a directory service is a centralized database that stores information about network resources such as users, groups, devices, and services. This information is often organized in a hierarchical structure, akin to a tree, for easy retrieval.

Each directory service uses an access protocol such as LDAP, that determines how clients query the directory, update information, or manage entries.

The primary purpose of a directory service is to enable user authentication. When a user tries to access a network resource like an application or file server, the directory service verifies their identity before granting them access. It does this by checking their login credentials (e.g username and password) against its records. Once authenticated, the directory service determines what resources the user is authorized to access based on their permissions and grants them access.

Directory services also maintain a wide range of user profile data like their address, phone number, job title, location, and other security credentials. And in most cases, they also support the synchronization of this data with apps and other services using a protocol like SCIM. This means when an admin creates a user account or updates its details in the directory, that change is propagated to all the apps connected to the directory.

Directory services serve as a backbone for identity and access management in:

• Enterprise networks: Managing user accounts, permissions, and access to resources like files, printers, and applications.
• Cloud environments: Offering cloud-based directory services to manage users and resources across cloud applications and services.
• Hybrid IT environments: Integrating on-premise directory services with cloud services.

Directory services have various use cases including:

• User management: They provide a structured, standardized way to store, manage, and access information about users, groups, and devices, supporting a wide range of authentication and authorization methods like email/password, social logins, and MFA.
• Single Sign-On (SSO): Centralizing authentication enables users to access multiple applications and services from a single place. An employee can log in once to the directory and gain access to services like email, document storage, and internal company portals without needing to authenticate separately for each service.
• Access control: Admins can use directory services to define and enforce who has access to which resource within a network. For example, an admin may restrict access to sensitive financial documents to only the finance department's members.
• Device management: Managing devices connected to a network, including computers, printers, and mobile devices, ensuring they meet security and configuration standards.
• Directory synchronization: In hybrid environments, directory services help synchronize on-premise directory services with cloud-based directories to ensure consistent user access and information across platforms.

Are directory services still used in 2024?

Yes, directory services are still used in 2024.

While cloud IdPs have significantly impacted identity management, especially with the shift towards cloud services and remote work, they have not made traditional directory services obsolete.

Many organizations operate in hybrid environments, utilizing both on-premises infrastructure and cloud services. Directory services are essential for managing on-premises resources, especially network resources like devices, file systems, and printers, while cloud IdPs focus primarily on managing access to applications and services. Most organizations will use a directory service and complement it with a cloud IdP.

Next steps

Most enterprises will want to connect their directory service to your app to manage access for their employees easily.

Instead of building each connection, one by one, use Directory Sync by WorkOS and save your engineering team months of dealing with integration headaches. With a single API-based integration, you can connect to major directory service providers like Active Directory, Google Workspace and Okta.

• Get started fast: With SDKs for every popular platform, and Slack-based support, you can implement Directory Sync in minutes rather than weeks.
• Events-based processing: While webhooks are also supported, WorkOS’s Events API means every SCIM request is processed in order, and in real-time. You’ll never miss a provisioning request again.
• Pricing that makes sense: Unlike competitors who price by monthly active users, WorkOS charges a flat rate for each company you onboard — whether they’re syncing 10 or 10,000 users with your app.

Explore Directory Sync by WorkOS.