LDAP vs Active Directory: Differences + What You Need to Know

LDAP and Active Directory (AD) are typically used together - but are not the same.

LDAP is a protocol used to access and manage directory information over a network while Active Directory is Microsoft's identity solution for managing just about everything on a Windows network - from user identities to what resources they can access.

Most of the confusion between LDAP and Active Directory comes from the fact that AD uses LDAP as a communication protocol, and sometimes these servers are referred to as Active Directory LDAP or LDAP Active Directory.

In this article, we’ll break down LDAP and Active Directory to show you how they work, where they each shine, and where they might fall short. Most importantly, we’ll cover where and when to use each.

LDAP vs Active Directory: Which is right for you + what are they?

Both LDAP and Active Directory are used in identity management but in different ways.

LDAP is a protocol used to access and manage data in directories. It's vendor-neutral and works across platforms including Linux, Windows, and macOS.

Active Directory is a directory service from Microsoft that is used by organizations to store and manage identities, authenticate users, and enforce access policies exclusively in Windows environments.

The main difference between LDAP and Active Directory is that LDAP is just a communication protocol, it’s not a directory or database that stores or manages identities like Active Directory.

Use non-Active Directory LDAP for on-premises deployments especially if your app requires access to local network resources behind a firewall.

Use Active Directory if you want to support access to your app through ADFS or Microsoft Entra.

Use Active Directory with LDAP if you want to authenticate users against Active Directory, using LDAP as the protocol.

What is LDAP?

LDAP (Lightweight Directory Access Protocol) is an open protocol used to access and maintain data from directories over a network.

These directories store information about employees (names, emails, passwords), devices (printers, phones, computers), and other resources within an organization. LDAP provides a standardized way of querying, creating, updating, and deleting entries within this directory.

It runs over the TCP/IP protocol and follows the client-server model. LDAP servers store directory data in a hierarchical structure and process requests from LDAP clients. These clients (could be your app) communicate with the LDAP server using the LDAP protocol to request or update information in directories.

LDAP-based directories can also be used for authentication since they can store user identity data and can therefore be used as a source of truth for verifying identities. In a typical authentication scenario, a user attempts to log in to an app by entering their credentials. The app sends a bind request to the LDAP directory, searching for a user entry that matches the provided credentials. The LDAP directory authenticates the user credentials against its database and if there’s a match, the user is granted access otherwise access is denied.

LDAP is vendor-neutral and can be implemented with any LDAP-compliant directory across different environments. In fact, apps can authenticate user credentials against Active Directory servers via LDAP.

Pros of LDAP

Below are some benefits of LDAP:

• Fast bulk searches: Thanks to indexing and organizing data hierarchically, LDAP-based servers are optimized for efficient read-heavy operations, making them exceptionally fast for bulk searches within large datasets.
  
  For example, when the HR department needs to quickly collect contact details for the thousands of employees in the company, the LDAP query specifies a search base aligned with the directory's hierarchy (e.g., location > department > individual employees) and applies filters on indexed attributes like department=engineering OR department=marketing AND employeeStatus=active.
  
  This method quickly narrows down and retrieves relevant contact information by targeting specific parts of the directory and using indexed attributes to filter the results.

• Platform-independent: One of LDAP's most significant advantages is its ability to function across different operating systems and environments – be it on Windows, Linux, macOS, or a mix of these.
• It’s a fully-fledged communication protocol: It's designed to support CRUD (Create, Read, Update, Delete) style actions on directory entries. It can be used to create new users, update access permissions, or even delete records from directories.

Cons of LDAP

Below are some of the cons of LDAP:

• Integration complexity: Integrating LDAP into an existing IT infrastructure can be complex, requiring a thorough understanding of both the protocol and the specific directory service your customer uses.
• Challenging in browser environments: LDAP was designed primarily for internal use within trusted networks and is not natively supported by web browsers. Basic LDAP implementations also do not necessarily include encryption.
  
  For web apps that need to access LDAP services from a browser, typically, a more secure approach is to communicate with the LDAP server via a backend application. This backend server manages LDAP communications securely and ensures sensitive data is not exposed directly to the browser environment.

What is Active Directory?

Active Directory (AD) is an identity and access management service developed by Microsoft. It stores information about network resources such as users, groups, and computers and allows administrators to manage these resources and user’s access rights.

It consists of a suite of tools for managing policies, security, and identities within a network. Some of these tools include ADFS which enables SSO across an organization’s boundaries and AD CS (Active Directory Certificate Services) which is responsible for creating and managing public key certificates. It therefore has a broader scope that includes not just directory services.

For it to be useful, AD requires a protocol (or a method) for querying, updating, removing information, and authenticating access to it. One such protocol is LDAP.

Pros of Active Directory

Below are some of the areas Active Directory shines:

• Extensive group policies: AD allows for centralized management of users, groups, and devices, making it easier to enforce security policies and access controls.
• Integration with Windows: Active Directory is tightly integrated with Windows environments, and offers enhanced security and seamless user experience with Windows-based apps and services.
• Single Sign-On: AD centralizes user credentials and lays the groundwork for SSO by storing a single set of credentials for each user. Users log in once using their AD details and access multiple apps. For SSO that goes beyond the organization network, it integrates with tools like ADFS and Microsoft Entra (formerly Azure AD) to allow authentication in external networks.

Cons of Active Directory

• Windows-centric: AD is deeply integrated with the Windows OS and does not integrate nearly as well with Linux, macOS, and other non-Windows systems.
• Set up complexity: Setting up your app to communicate with Active Directory (AD) can be complex. You need to understand AD's structure, including domains, trees, and forests, as well as its authentication protocols like LDAP or Kerberos.

What are LDAP and Active Directory used for? Can you use both?

LDAP is a protocol used for accessing and managing information in a directory service like Active Directory and enables operations like querying user information and authenticating users against data in these directories.

Active Directory is typically used as a directory service by enterprises operating Windows environments, to manage users and other resources, authenticate, and enforce security policies.

Organizations may also use both together! They can manage AD's resources using LDAP commands.

FAQs

Which one should you use, LDAP or Active Directory?

Active Directory is the most widely used protocol within enterprises especially the ones that use Microsoft products and services. LDAP is used by organizations that want a lightweight solution to access directory information without being tied to a specific vendor.

You may end up having to support both in your application – it’ll ultimately depend on what your customers use.

Can you use LDAP without Active Directory?

Yes, you can use LDAP without Active Directory. LDAP is not tied to any specific directory service or vendor and organizations often use it with different directory services other than Active Directory, such as OpenLDAP, Apache Directory Server, or 389 Directory Server.

What is the difference between LDAP and Active Directory?

The main difference between LDAP and Active Directory is that, unlike Active Directory, LDAP is not a directory but a protocol that can be used to manage access to directories. Additionally, LDAP is an open protocol and therefore vendor-neutral  while Active Directory is tied to Windows environments.

What is the role of LDAP in Active Directory?

LDAP acts as a communication protocol between AD and your app or the services that need to access or manage data in AD. It provides a standardized method for querying and modifying the directory services data stored in Active Directory. This includes operations like searching for user information, authenticating users, and updating user attributes.

Is LDAP Secure?

LDAP is only as secure as its implementation. By itself, LDAP can transmit data in plaintext, which might pose security risks, especially over unsecured networks. However, LDAP supports several mechanisms to enhance security:

• LDAPS (LDAP over SSL/TLS): Runs over SSL (Secure Sockets Layer) or TLS (Transport Layer Security), encrypting the data transmitted between the LDAP client and server protecting it from eavesdropping or interception by hackers or thieves.
• SASL (Simple Authentication and Security Layer): LDAP supports SASL, which allows it to use various authentication methods, beyond simple username and password, for a more secure authentication process.

Next steps

If you’d rather not worry about whether to integrate with Active Directory or another LDAP-based directory, use a done-for-you authentication service like WorkOS, and support both with just a few lines of code:

• Get started fast: With SDKs for every popular platform, and Slack-based support, you can implement SSO in minutes rather than weeks.
• Avoid the back-and-forth: WorkOS’ Admin Portal takes the pain out of onboarding your customers’ IT teams and configuring your app to work with their identity provider.
• Pricing that makes sense: Unlike competitors who price by monthly active users, WorkOS charges a flat rate for each company you onboard - whether they bring 10 or 10,000 users to your app.

Explore Unified SSO by WorkOS.