How OIDC Works<\/strong><\/h2>\n\n\n\nOIDC extends the OAuth protocol so that client services (your applications) verify user identities and exchange profile information through OpenID providers via RESTful APIs that dispatch JSON web tokens (JWTs) to share information during the authentication process. The providers are essentially authentication servers.<\/p>\n\n\n\n
Many developers are attracted to this approach because it\u2019s highly scalable, flexible across platforms, and is relatively simple to implement. Its main components are a unique user ID workflow with OAuth underpinnings.<\/p>\n\n\n\nSource: OpenID Foundation<\/em><\/figcaption><\/figure>\n\n\n\nOpenID Architecture and Components<\/strong><\/h3>\n\n\n\nOpenID Connect (OIDC) is built on top of the OAuth 2.0 protocol and uses a set of key components to facilitate secure authentication. The primary components in OIDC include:<\/p>\n\n\n\n
\nEnd-User<\/strong> (the user trying to authenticate)<\/li>\n\n\n\nClient<\/strong> (the application requesting authentication)<\/li>\n\n\n\nAuthorization Server<\/strong> (the IdP responsible for authentication)<\/li>\n\n\n\nResource Server<\/strong> (where the user’s data resides)<\/li>\n<\/ul>\n\n\n\nOIDC introduces the ID Token, a JWT (JSON web token) containing user identity information, which is issued by the Authorization Server. It also relies on access tokens for securing API access and refresh tokens to maintain long-term sessions.<\/p>\n\n\n\n
OpenID Authentication Flow<\/strong><\/h3>\n\n\n\nOIDC follows a structured authentication flow that starts when the client application redirects the end user to the Authorization Server\u2019s login page. These steps include:<\/p>\n\n\n\n
\nThe user authenticates via the IdP, which then sends an Authorization Code<\/strong> back to the client.<\/li>\n\n\n\nThe client exchanges this code for an ID Token<\/strong> and an Access Token<\/strong> by making a request to the Authorization Server\u2019s token endpoint.<\/li>\n\n\n\nThe ID Token<\/strong> provides the client with user identity information (e.g., name, email), while the Access Token<\/strong> is used to access protected resources.<\/li>\n<\/ol>\n\n\n\nThis flow ensures that user authentication is secure and that the client can safely obtain user information without exposing sensitive credentials.<\/p>\n\n\n\n
Choosing Between SAML and OpenID<\/strong><\/h2>\n\n\n\nCriteria for Decision Making<\/strong><\/h3>\n\n\n\nWhen choosing between SAML and OpenID Connect, consider factors like the type of application, security requirements, and system architecture.<\/p>\n\n\n\n
SAML is a good choice for legacy, enterprise environments requiring robust security for web-based SSO and where XML-based communication is preferred. It\u2019s ideal for large-scale, centralized authentication in corporate settings.<\/p>\n\n\n\n
On the other hand, OIDC is better suited for modern applications, particularly in mobile and cloud-native environments. It\u2019s easier to implement, with RESTful APIs and JSON, and integrates well with OAuth 2.0 for fine-grained access control. For organizations needing lightweight, scalable solutions with support for distributed systems, OIDC may be the preferred option.<\/p>\n\n\n\n
Best Use Cases for SAML<\/strong><\/h3>\n\n\n\nSAML excels in enterprise environments where legacy applications require secure web-based SSO, often in large-scale, centralized setups.<\/p>\n\n\n\n
It is particularly well-suited for regulated industries where strict compliance and audit requirements exist, such as healthcare, finance, and government. Examples include enterprise applications like SharePoint, Salesforce, and SAP, where secure user authentication across multiple internal systems is essential.<\/p>\n\n\n\n
SAML also works well for federated identity management in B2B or B2C scenarios.<\/p>\n\n\n\n
Best Use Cases for OpenID<\/strong><\/h3>\n\n\n\nOpenID Connect is ideal for modern, web-based, and mobile applications, especially in cloud-native and microservices environments.<\/p>\n\n\n\n
It is the preferred choice when integrating with third-party identity providers like Google, Facebook, or GitHub for user authentication. OIDC works seamlessly for applications requiring fast, scalable authentication, such as SaaS applications (e.g., Slack, Salesforce, Dropbox). Additionally, it\u2019s highly effective in API-driven environments, where microservices need secure and lightweight user authentication via tokens.<\/p>\n\n\n\n