What Is Single Sign-On (SSO)?

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A single sign-on (SSO) is an authentication process that allows users to access multiple applications with one set of credentials. Users can enjoy the convenience of only managing a single set of credentials for multiple applications. In turn, SSO has become a widely-used solution for its user-friendliness, improved safety features, and streamlining the management of various services.

The concept of single sign-on can be applied to both internal enterprise systems and external web-based services. In a business environment, employees may use SSO to access their email, file storage system, project management tools, or other work-related applications using just one username and password combination. Similarly, consumers might utilize an SSO service like a Google or Facebook login when accessing multiple connected mobile applications or websites.

Implementing single sign-on effectively within an organization or application ecosystem requires integrating with a centralized identity provider (IdP). The IdP is the authoritative source for user identity information during the authentication process. Some common protocols IdPs use include Security Assertion Markup Language (SAML) and OpenID Connect (OIDC). These protocols enable seamless communication between service providers – such as individual apps or websites – and the central IdP responsible for verifying user identities.

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How Does Single Sign-On Work?

Single sign-on (SSO) is a service that simplifies the authentication process by allowing users to access multiple applications with a single set of login credentials. The SSO system consists of two main components: the identity provider that verifies user identities and the service providers that grant access to their respective applications.

The typical login flow for an SSO-enabled environment involves the following steps:

  1. A user logs into a central identity provider using their unique credentials.
  2. The identity provider authenticates the user’s information and generates a digitally signed token called an SSO token.
  3. When requested by the user, this token is sent to service providers connected to the system.
  4. The service providers verify the token’s validity, ensuring successful authentication before granting access to their application(s).

In addition to traditional username/password combinations, many SSO solutions incorporate multifactor authentication (MFA) or risk-based authentication methods for added security. The popular protocols used in implementing SSO – SAML and OIDC – help standardize communication between identity and service providers, making it easier for organizations to integrate various systems seamlessly.

SSO allows users to access multiple connected mobile or web applications with a single identity, eliminating the need to remember multiple login credentials. This improves the user experience and reduces the risk of password theft and reset issues. Additionally, SSO solutions can help organizations gain access to valuable identity information used to improve customer loyalty and drive business growth.

What Is an SSO Token?

SSO works based on a trust relationship between an application, known as the service provider, and an identity provider, such as 1Password or OneLogin. This relationship is often based on a certificate or SSO token exchanged between the identity provider and service provider.

An SSO token is a digitally signed piece of data that validates a user’s successful authentication. It contains essential user identity information, such as username, email address, and associated attributes or roles. In short, SSO tokens are a critical component of the single sign-on system.

When a user logs in with their SSO login, an authentication token is created and stored either in their browser or the SSO solution’s servers. This token contains the required data to identify the user for the domain. The token can be passed to the original domain by a redirect and contains identifying information about the user, such as their email address and information about which system is sending the token.

What Are the Benefits of Single Sign-On?

Enterprises, small to medium-sized organizations, and individuals can use SSO to streamline the management of multiple accounts and passwords. It reduces time spent re-entering passwords for the same identity, can simplify administration procedures, and reduces IT costs.

Implementing an SSO system offers numerous advantages for businesses and users alike. Here are some key benefits:

  • Improved user experience: Users can access multiple applications with just one set of credentials, eliminating the need to remember multiple passwords or login details. This convenience leads to increased customer loyalty and reduced instances of users abandoning services due to forgotten passwords.
  • Improved security: With SSO, organizations can implement additional layers of protection, such as multifactor authentication (MFA) and risk-based authentication, making it more difficult for cyber attackers to gain access using stolen credentials. Moreover, users only have one password to manage, so they’re less likely to reuse weak passwords across different accounts.
  • Fewer password reset issues: By consolidating login information into a single identity provider, businesses can reduce the number of password-related support requests. According to research from Gartner, nearly 50% of all IT help desk calls are related to password resets, and resetting an employee’s password isn’t a quick, one-click action. SSO systems can help alleviate this costly inconvenience.
  • Easier integration with other systems: Many modern SSO solutions use industry-standard protocols like SAML, OpenID Connect, or OAuth, enabling seamless integration between various service providers and applications.
  • Increase in productivity: The streamlined authentication process allows users faster access to their applications without multiple logins, resulting in better work efficiency.

SSO also benefits IT teams by enabling stronger and more realistic password policies while reinforcing security by minimizing the risk of password-related security breaches, such as brute force attacks and other cyber threats.

How Secure Is SSO?

SSO systems are designed to provide a secure and convenient authentication process for users. Nevertheless, the safety of SSO depends on various components such as setup, associated protocols, and any other cybersecurity measures taken by the organization.

Many SSO solutions use industry-standard protocols like Security Assertion Markup Language (SAML), OpenID Connect, or OAuth 2.0 to ensure secure communication between service providers and identity providers. These protocols typically involve digitally signed tokens that validate successful authentication. Additional security measures include:

  • Risk-based authentication: Some organizations combine SSO with risk-based authentication methods like two-factor authentication (2FA) or multifactor authentication (MFA). This adds an extra layer of protection against password theft and unauthorized access attempts.
  • Password management: A well-implemented SSO system can help reduce password reset issues by centralizing user credentials in one place. Users only need to remember their master password instead of multiple passwords for different accounts.
  • Data encryption: To further enhance security, sensitive data transmitted during the login process should be encrypted using robust encryption algorithms like AES-256 or RSA-2048.

In addition to these technical safeguards, organizations must adopt best practices in user awareness training, policy enforcement, and regular audits to maintain a robust cybersecurity posture when implementing an SSO solution. While no single technology can guarantee absolute security from cyber threats, combining single sign-on with other layers of defense significantly improves overall protection.

SSO is generally more focused on providing access than restricting it. Simply put, greater accessibility is not always a good thing. If an attacker gains access to an authenticated SSO account, they’re automatically granted access to all associated applications, environments, systems, and data sets linked to that specific account.

While the additional layers of security outlined above can help mitigate potential threats, failure to properly utilize and reinforce an SSO system can pose significant security risks, heightening concerns related to malware-based attacks, data breaches, and other common cyber threats.

How to Implement Single Sign-On

Integrating an SSO setup can help improve user experience and security for your organization. To effectively implement an SSO system, follow these steps:

  1. Select an Identity Provider (IdP): Choose a reliable IdP that supports industry-standard protocols like SAML or OpenID Connect (OIDC). This manages user identities and authentication requests.
  2. Integrate applications with the IdP: Configure each application in your ecosystem to use the selected IdP for authentication. This may involve updating application settings or working with developers to add support for SSO.
  3. Add Multifactor Authentication (MFA): Enhance security by implementing multi-factor authentication, which requires users to provide additional verification beyond their passwords, such as a fingerprint scan or a one-time code sent via SMS.
  4. Create access policies: Define granular access policies based on job role, location, device type, and risk level. These policies help ensure only authorized users gain access to sensitive resources while minimizing password theft risks.
  5. Educate end-users: Inform employees about how SSO works and its benefits so they understand why it’s being implemented. Address any concerns regarding privacy or potential changes in workflow due to the new system.
  6. Monitor and maintain: Regularly review logs, reports, and analytics provided by your SSO solution to identify potential security threats or areas for improvement. Continuously update policies and configurations as needed based on these insights.

Incorporating an SSO system can be a complex process, but with careful planning and execution, it can significantly improve the user experience while bolstering your organization’s cybersecurity measures.

How Proofpoint Can Help

Implementing a robust single sign-on solution is crucial for organizations needing to enhance their security and user experience. Proofpoint offers comprehensive integration with various services, helping organizations streamline their authentication process while preventing credential phishing attacks and account takeover attempts.

Designed to deliver adaptive controls for high-risk users, Proofpoint’s solutions integrate with popular providers like Okta, Microsoft Azure, and Google Workspace. Your organization can leverage its existing identity management platform investment without requiring complex configurations or customizations.

Proofpoint’s people-centric security solutions enable organizations to combine SSO with multifactor authentication and risk-based authentication, providing additional protection against password theft and unauthorized access. Integrating these features into your organization’s existing infrastructure allows you to optimize user authentications with one set of login credentials while benefiting from reinforced security measures.

Incorporating SSO solutions into your business strategy can help you create a frictionless user experience while safeguarding sensitive data from potential cyber threats. To learn more about how Proofpoint can help your organization implement a successful single sign-on system, contact us for more information.

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