An AWS IAM role is essentially a virtual identity within your AWS account that you can assign specific permissions to. It works differently from an IAM user in a few keyways:
Who can use it:
IAM User: Associated with a single individual and has long-term credentials like a username and password.
IAM Role: Not tied to a specific person, but rather can be assumed by various entities like applications, other users, or services that need temporary access.
Credentials:
IAM User: Has long-term static credentials that may pose security risks if leaked or misused.
IAM Role: Provides only temporary, short-lived security credentials upon assuming the role, enhancing security as they expire and don't need manual rotation.
Use cases:
IAM User: Suitable for individual users who frequently access AWS resources with consistent permissions.
IAM Role: Ideal for:
Applications running on EC2 instances: Granting them temporary access to AWS resources without embedding hardcoded credentials.
Federated users: Providing secure access to users from external identity providers.
Cross-account access: Enabling users in one AWS account to access resources in another securely.
Workforce identities: Allowing temporary access to specific resources for specific tasks.
Security best practices:
Use IAM roles whenever possible for programmatic access or applications running on AWS resources.
Implement least privilege, granting roles only the minimum permissions needed for their specific tasks.
Regularly review and update role permissions to ensure they remain aligned with current needs.
Use tools like AWS Security Hub and IAM Access Advisor to monitor and audit role usage and permissions.
Here are some additional resources you might find helpful:
AWS IAM Roles Documentation: https://docs.aws.amazon.com/iam/
Manage IAM Roles: https://docs.aws.amazon.com/managedservices/latest/onboardingguide/create-iam-role.html
What is IAM?: https://docs.aws.amazon.com/iam/