If you’re looking into LDAP (Lightweight Directory Access Protocol) and SSO (Single Sign-On), odds are you want more clarity on it. So LDAP vs SSO, what’s the difference?
Here are the facts - LDAP is a protocol that was more popularly used prior to SSO. But does it still have benefits? Is it worth using if you’re trying to keep your authentication agile?
In this article, we’ll cover how LDAP and SSO work, their key differences, and help you pick the right one for your company. So here’s what you need to know…
What is LDAP (Lightweight Directory Access Protocol)?
LDAP is a protocol designed to manage and retrieve directory-based information, commonly used for authentication in enterprise networks. This protocol was commonly used in applications before the advent of other token-based authentication, like SAML and OAuth.
LDAP stores user credentials, permissions, and attributes in a structured format, making it a practical choice for businesses that rely on centralized identity management. A good example of this would be the framework in Azure Active Directory (Now Entra ID). LDAP was used extensively software has moved more towards SAML and OAuth.
However, many legacy applications still use LDAP.
Benefits of LDAP
- Centralized User Management: IT teams can store and maintain credentials in a single directory. This removes the need for companies to manually update access or passwords for multiple users.
- Compatible With Legacy Systems: A lot of legacy software does not support SSO protocols like SAML, OIDC, and OAuth.
- Scales with Large Enterprises: Supports thousands of users without causing performance issues.
- Custom Access Control: Permissions can be structured based on roles, departments, or security policies.
How LDAP Works
LDAP follows a client-server model. When users attempt to log in, their credentials are sent to the LDAP server, which checks the directory and decides whether to grant access.
LDAP stores usernames, passwords, and access rights in one directory and grants users access with the use of a set of credentials. The application then needs to check the LDAP tool to see if you have access to it.
What is SSO (Single Sign-On)?
Single sign-on (SSO) allows users to log in once and access multiple applications without re-entering credentials. Instead of storing usernames and passwords for every application separately.
By doing this, SSO authenticates users through a central identity provider (IdP), issuing tokens for application access.
Benefits of SSO
SSO is a new type of authentication and comes with its own range of benefits. While LDAP is supported by many more legacy applications, SSO is the new norm because it makes some aspects better, we’ve listed them below:
- Simplified Access: Users move between applications without logging in repeatedly. This also becomes a lot easier with SSO providers and IAM software that allow passwordless authentication methods like OTPs, magic links, and even QR codes.
- No Need for Repeated Logins: SSO removes the need for users to constantly need to log in to multiple software, and with the APIs and mobile apps support, it’s a lot easier to make sure of this.
- Fewer Password-Related Problems: Reduces password fatigue and lowers the number of reset requests.
- Stronger Security Measures: When combined with multi-factor authentication (MFA), SSO improves security while keeping things user-friendly.
How SSO Works
SSO relies on authentication protocols like SAML, OAuth, or OpenID Connect.
When a user logs in, the SSO provider confirms their identity and issues a token, allowing them to access multiple applications without entering their credentials again.
This means they have access to multiple different applications added to your SSO system without needing to keep logging into apps again and again (Which is the case with LDAP).
SSO Protocols and Implementations
SSO is more of an umbrella term for multiple protocols that allow the usage of single sign on. To simplify this further, these are typically boiled down to SAML, OAuth, OIDC, and in rare cases even FIDO.
- SAML (Security Assertion Markup Language): Often used in enterprise settings to manage identity federation.
- OAuth 2.0: A go-to option for API authentication and third-party connections.
- OpenID Connect: An extension of OAuth 2.0 that supports user authentication for web and mobile apps.
LDAP vs SSO: Key Differences
1. Authentication Flow
- LDAP works by checking user credentials against a directory service like Active Directory or OpenLDAP. Every time a user logs in to an application, their credentials must be verified separately.
- Unless configured otherwise, users have to authenticate for each tool or platform they use.
- SSO, on the other hand, simplifies authentication by allowing a single login to unlock multiple applications.
- SSO relies on modern authentication protocols like SAML, OIDC, and OAuth to verify users through an identity provider, eliminating the need for repeated logins.
2. Security Differences
LDAP vs SSO - Which has better security? Well, LDAP is still widely used for authentication in legacy applications, but primarily depends on usernames and passwords, which can be vulnerable to credential-based attacks.
- While encryption and MFA can strengthen security, LDAP alone lacks the multi-layered approach seen in modern authentication methods.
- SSO, while more secure through its use of encrypted tokens and passwordless authentication, introduces a potential single point of failure. If the SSO provider is compromised or experiences downtime, users may lose access to all connected applications.
- That said, pairing SSO with MFA or risk-based authentication significantly reduces security risks and is easy to integrate, making it harder for attackers to misuse credentials that get leaked.
3. User Experience
LDAP requires users to log in separately for each application unless it’s combined with SSO or another centralized authentication method. This can slow things down, especially in workplaces where employees switch between multiple tools throughout the day.
- LDAP vs SSO when compared in terms of UX, SSO comes out on top. Single sign-on has a much smoother experience.
- With a single login, users can move freely across different applications without worrying about remembering multiple passwords.
- SSO improves productivity while cutting down on login fatigue. While LDAP supports legacy applications which many SSO protocols do not.
4. Common Use Cases and Financial Considerations
LDAP works well for businesses that need an internal authentication system for on-premise applications, local networks, or legacy systems.
So LDAP vs SSO - Which is more common? Well, LDAP is a solid choice when centralized credential storage is required, but SSO is a lot better when it comes to simplifying access.
SSO is widely used in cloud-based environments, SaaS platforms, and enterprise applications where quick and hassle-free access is a priority.
- LDAP Maintenance Costs: Requires IT resources to manage user directories and authentication servers.
- SSO Cost Savings: Fewer password reset requests mean less strain on IT teams, leading to less spend on administrative work.
Using LDAP and SSO Together
Many businesses combine LDAP and SSO to balance security and convenience. A common approach is using LDAP for internal authentication while SSO handles access to cloud applications.
Known as LDAP SSO authentication, this is SSO built on an LDAP, enabling access to even legacy apps.
Security Considerations in Authentication Protocols
- LDAP Risks: Poor encryption or plaintext credential storage can lead to security breaches.
- SSO Risks: A compromised SSO credential can grant access to multiple applications. Using MFA helps counteract this risk.
- Best Practices: Always encrypt data, require MFA, and audit access logs regularly.
When to Use LDAP vs SSO in Your Organization
When to Use LDAP
- Your business primarily runs on-premise applications.
- You need a structured directory for credential storage.
- Authentication is mostly for internal tools.
When to Use SSO
- Your business relies on multiple cloud-based services.
- You want to simplify access across different platforms.
- User experience and productivity are top priorities.
When to Use Both
- With LDAP single sign-on, you manage a mix of legacy and modern applications.
- Internal directories handle on-premise authentication, while SSO manages cloud access.
- You can use LDAP single sign-on when you need centralized authentication without having to disrupt existing systems.
Why Work With LDAP and SSO Using Infisign
So we’ve covered the difference between SSO and LDAP. In many cases, a combination of both works best—LDAP handles internal authentication while SSO takes care of cloud-based access.
Unlike traditional LDAP-based authentication, Infisign is built with SSO and modern security protocols with over 6000+ app and SDK integrations —meaning no outdated password management or security gaps for attackers to exploit.
While LDAP stores credentials, SSO simplifies access, and Infisign goes further with passkey support, directory sync, and tenant-based pricing—all included at no extra cost. Scalable, secure, and cost-effective, Infisign is the smarter alternative to legacy authentication. Try it free today!
