How does OAuth 2.0 work?

OAuth 2.0 is an authorization framework that enables secure delegation of access to resources without sharing user credentials. It simplifies user experiences by allowing third-party applications to access user data with their permission, using tokens instead of passwords. This article explains OAuth 2.0's core components, flows, best practices, use cases, and limitations, providing a comprehensive guide for developers and architects.

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Core Technical Concepts/Technologies

• OAuth 2.0: Authorization framework for secure resource access delegation.
• Tokens: Access tokens, refresh tokens, and ID tokens.
• Flows: Authorization Code, Client Credentials, Device Code, Implicit, and Resource Owner Password Credentials.
• Roles: Client, Resource Owner, Authorization Server, Resource Server.
• PKCE (Proof Key for Code Exchange): Security enhancement for mobile and public clients.
• OpenID Connect: Identity layer built on OAuth 2.0 for authentication.

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Main Points

• Why OAuth 2.0?

  • Solves the problem of sharing credentials by using tokens for secure access delegation.
  • Enables third-party apps to access user data without exposing passwords.

• Core Components

  • Client: Application requesting access.
  • Resource Owner: User granting access.
  • Authorization Server: Issues access tokens.