AWS IAM - Identity and Access Management

IAM Identity Center (AWS Single Sign-On - SSO)

What is IAM Identity Center?

AWS Identity Center (formerly AWS SSO) is a centralized user authentication and authorization service that allows organizations to manage access to multiple AWS accounts and applications.

Why Was IAM Identity Center Introduced?

Before IAM Identity Center, managing access for multiple AWS accounts was complex because: 1. Companies had multiple IAM users across different AWS accounts, creating duplication. 2. Organizations using Microsoft Active Directory (AD) had to manually sync users with AWS IAM. 3. There was no single sign-on (SSO) capability for AWS Management Console and third-party apps.

How Does IAM Identity Center Work?

  • Allows centralized user management across multiple AWS accounts.
  • Supports single sign-on (SSO) so users log in once and access multiple accounts.
  • Integrates with Microsoft Active Directory (AD) and third-party identity providers (IdPs) (e.g., Okta, Google Workspace, Azure AD).

IAM Identity Center vs. Traditional IAM

Feature IAM IAM Identity Center
User Management AWS-only IAM Users External Identity Providers (AD, Okta)
Access Scope Per AWS Account Across Multiple AWS Accounts
Login Method IAM Credentials (Username/Password) SSO (Single Login for All)
Best for Small Teams Large Organizations with Multiple AWS Accounts

Use Cases of IAM Identity Center

  1. Multi-Account Access → Companies with multiple AWS accounts can assign access from one place.
  2. Active Directory Integration → Companies using AD can extend access to AWS services.
  3. SSO for Third-Party Applications → Easily log in to third-party SaaS applications (e.g., Salesforce, Jira).
  4. Federated Access for Employees → Employees can log in using their corporate credentials.

How IAM Identity Center Integrates with Active Directory (AD)?

  • AWS Identity Center can sync users and groups from an on-premise Microsoft Active Directory.
  • Users can log in with their corporate credentials without needing IAM users.
  • This is done via AWS Directory Service.

Conclusion

AWS IAM Identity Center is not a replacement for IAM but an addition that simplifies user access management, especially for companies using multiple AWS accounts or third-party identity providers.