What Is Single Sign-On (SSO)?

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“Single sign-on” (SSO) is an authentication method that allows users to enter one set of authentication credentials to access multiple websites, applications, and services. The goal of SSO is to streamline the authentication process by eliminating the need to enter different usernames and passwords for each resource.

Although several SSO options exist, they all strive to offer benefits to both users and businesses.

How Single Sign-on Works

Single sign-on involves authenticating a user’s identity and then authorizing them to access the service or application that the user is requesting. It achieves this by retrieving the user’s profile, which is securely stored in the SSO system, HR system, or a directory like Microsoft’s Active Directory.

SSO validates the user’s credentials, such as their correct username and password. It can also add extra security layers and validate additional information like the user’s IP address, location, time of day, device info, and physical checks to add additional layers of security beyond the traditional login methods.

• IP address: Some SSO solutions offer a security feature that verifies the user’s IP address when they attempt to log in.
• Date and timestamp: Verifies the current date and time on the device against an authentication server to validate that the device is synced with the server.
• Geolocation: Checks the user’s location before granting access to resources to prevent unauthorized access from suspicious locations.
• Device information: Examines the status of the device. These checks can include operating system versions, if the device has the most up-to-date security patches and updates, or if the organization approves and manages the device.
• Biometrics: Scans a user’s physical attributes, such as facial features or fingerprints, to validate the requestor’s identity.

As previously mentioned, the goal is to add extra layers of security to validate user authentication. SSO is similar to another authentication method known as multi-factor authentication.

Types of SSO Solutions

All SSO services aim to streamline the authentication process. However, several types of single sign-on (SSO) solutions exist to be considered. These include password synchronization, enterprise SSO, federated SSO, web SSO, and mobile SSO:

• Password Synchronization: This is the simplest and most common form of SSO, where a single username and password are automatically updated and used across different systems or platforms.
• Enterprise SSO: This service captures user credentials via a browser extension or software agent. The service then replays the credentials to different applications or websites. 
• Federated SSO: Federated SSOs use a standard protocol, such as OAuth or OpenID Connect, to exchange user credentials and information between different systems or domains. The user logs in to an identity provider (IdP), like Google or Microsoft, and then the IdP sends a token to the requested service provider (SP), like Spotify. The service verifies the user’s identity with the identity provider and grants access.
• Web SSO: This service uses cookies to maintain user sessions across different web applications or resources within the same network. The user logs into a centralized server and is granted a session cookie to access all resources on the same server. Although web SSOs can improve the user’s web browsing experience, they can also lead to security issues if the cookie is stolen or tampered with.
• Mobile SSO: Mobile SSOs leverage a mobile device’s native features, such as biometric authentication with a face scan or fingerprint, to authenticate users on mobile applications or websites without entering their credentials.

When choosing the type of SSO service, organizations must review their networks and infrastructure to determine which one works best for them. However, there are also several benefits to implementing the right SSO service.

Key Benefits of Using SSO for Organizations

Users and organizations can benefit from using SSO solutions. Some of these benefits include improved security, better access control, and an overall increase in production:

• Improved security: SSO can improve security by enabling security features like strong passwords, multifactor authentication, and device checks before granting access.
• Centralized access control: Administrators and IT staff can manage permissions and access levels from a single point. SSOs can also help with logging and monitoring user accounts and activities.
• Increased user productivity: SSO enhances productivity by eliminating the need to use and remember multiple passwords to gain access to every resource. SSO requires users to use one set of credentials to access multiple applications. Users can leverage more resources to improve their productivity and efficiency by reducing password fatigue.

SSOs benefits depend on the type of SSO service and vendor. For example, enterprise password managers provide a single place for users to authenticate and manage their credentials. This offers credential management for each integrated resource and delivers an SSO experience to the user.

Additional administrative features in enterprise password managers include assigning and revoking access to certain apps, viewing password health among the user base, triggering additional authentication measures, and connecting to services like Microsoft Active Directory.

Integrating SSO with Multi-factor Authentication

SSO is all about users gaining access to all of their resources with a single authentication. In contrast, multi-factor authentication (MFA) focuses on the stronger verification of the user’s identity, which is often used for a single application. MFA requires users to authenticate by providing additional information beyond their login credentials. Examples of the extra information are things you may know, currently possess, or have biologically:

• Something you know: These can be things users must memorize, like PIN codes or answers to personal questions.
• Something you have: This form of authentication involves using a physical object like a physical token, an app on your device that produces a code, or an authentication key like a YubiKey or USB device.
• Something you are: Users authenticate into the resource by using their physical attributes. These include biometric scans like fingerprint and retina scanners.

While SSO can be used for most systems and applications, MFA can be added to access more sensitive information. For example, SSO credentials can give users access to several routine systems, such as email. But when you try to use the corporate VPN or enter systems via a smartphone, an MFA code is required as a further authentication method. After validating the user, the single sign-on system allows access to the requested resource. 

As cloud networks, work-from-home, and bring your own device (BYOD) have evolved, tiered access has become more prevalent. In addition, as most network breaches occur through stolen or hacked passwords, multi-factor authentication and network access controls increasingly complement single sign-on. Finally, MFA is often a requirement for regulated data as a way of satisfying government mandates.

3 Best SSO Providers

SSO products help teams manage user identities and grant access to company applications. They play a critical role in protecting sensitive data and applications because SSO reduces the risk that a threat actor could hack an application. While there are many to choose from, three that stand out: Okta, OneLogin, and Microsoft Entra ID.

Okta

Okta is a popular IAM and SSO provider that offers many identity management features, including temporary access and device assurance policies. Okta’s thousands of prebuilt app connectors make it one of the best SSO solutions.

Okta offers a 30-day free trial with their SSO service starting at $2 per user, per month. They also offer several other features for an additional cost per feature.

OneLogin

OneLogin is an enterprise-grade IAM platform for workforces and customers. It offers MFA, advanced directory features, mobile identity management, command line tools, and API access for developers.

OneLogin has a free trial, their advanced plan starts at $4 per user a month, and professional plans start at $8 per user a month when bundled with other services. They also provide pricing options for SMBs under 50 employees.

Microsoft Entra ID

Microsoft Entra ID is an identity governance and management platform for Windows organizations. Entra ID integrates with other Microsoft products like Defender for Cloud and Sentinel. It also offers passwordless authentication, lifecycle management, and custom session length features.

Microsoft has a free plan that has some partial IAM features. Their P1 plan starts at $6 a user and their P2 plan starts at $9 per user a month after a 30-day free trial.

To the full list of solutions with their features, pros and cons, and pricing, read our best single-sign-on solutions article.

SSO solutions can bring many benefits to your organization. However, IT and security team members must implement them properly to avoid potential complications.

Common Challenges of Implementing SSO

As mentioned before, SSO has many benefits. However, SSO also has limitations and potential risks if not implemented properly. Not knowing what applications and resources you have before installing new technologies can cause compatibility issues, bottlenecks, and security risks:

• Compatibility issues: While SSOs integrate with several applications and programs, many are incompatible. Organizations should be careful when choosing an SSO provider. Otherwise, they can face challenges when integrating it into their network.
• Single point of failure: While SSOs provide simplicity by only using one set of credentials to access several resources, it is also a significant concern that SSOs can create a single point of failure. For example, if the SSO system crashes, users may be unable to access any connected applications or services.
• Phishing: If a user’s SSO credentials are compromised in a phishing or social engineering attack, the attacker could gain access to all connected systems associated with that user.

As with any technology, it’s important to have a full and clear picture of the landscape before implementation. Performing routine checks of your network and systems not only helps you keep your infrastructure secure and up to date, but it also will help you prepare for any upgrades like implementing SSO services.

4 Best Practices for Using SSO

SSO systems will not be effective if organizations aren’t following best practices. They must clearly understand their infrastructure, employ strong authentication policies, use encryption to protect sensitive information, and keep a close eye on your network. Here are some key practices to assist you in your implementation process:

• Clearly define the SSO strategy: Organizations must ensure the SSO solutions they explore are compatible with their existing networks and infrastructure. They should also consider options for their organization’s growth and scalability, unique needs for the company, compliance with standards and regulations, and other needs.
• Use strong authentication: If your password is compromised, attackers will have access to all your applications. Therefore, you should use strong passwords or passkeys and add multi-factor authentication to add an extra layer of security.
• Use strong encryption: Ensure all credentials and data transmitted across your network are encrypted. This helps prevent malicious actors from intercepting tokens during a user’s session. Encryption protects sensitive data and ensures the information remains confidential.
• Implement logging and monitoring: Real-time monitoring allows IT and security teams to see who is accessing what resource, when they are doing it, and from where in real-time. This allows them to more efficiently detect and respond to any issues or suspicious activity and enhance your organization’s security posture.

Ensuring a robust SSO system involves more than just finding the best technology or vendor. It is recommended that companies thoroughly review their network security architecture and research different vendors and solutions before deploying it.

Bottom Line: SSO Provides a Strategic Approach to Security

Single sign-on streamlines access and bolsters security. However, while the benefits of SSO are significant, organizations must also carefully consider potential challenges. By following best practices, businesses can use SSO to create a secure and efficient environment. Therefore, a well-planned strategy is essential for any organization to enhance its security posture and increase user productivity and overall experience.

For more information on security best practices and their benefits, check out this article.