AWS IAM: Who Can Access What?
Understand how AWS IAM manages identities and permissions, and how Users, Groups, Roles, and Policies help control access to AWS resources.
When working with AWS, creating resources is not enough. We also need to control who can access them and what they can do.
That is the purpose of AWS Identity and Access Management (IAM): managing identities and permissions securely.
An important concept is understanding the difference between authentication and authorization. Authentication answers “Who are you?”, while authorization determines “What are you allowed to do?”
Users, Groups, Roles, and Policies
IAM provides different components to organize access.
Users represent individual identities. Groups allow us to organize users who need similar permissions.
Roles provide permissions that can be assumed by users, applications, or services. For example, an application running on EC2 can use a Role to access an S3 bucket without storing credentials in the code.
Policies define which actions are allowed or denied and which resources they apply to.
Least Privilege
One of the fundamental principles of IAM is Least Privilege: granting only the permissions necessary to perform a task.
If an application only needs to read files from an S3 bucket, it does not need full access to S3.
Why does it matter?
As an environment grows, controlling access becomes increasingly important. IAM helps ensure that users, applications, and services have only the permissions they need.
In the end, the idea is simple: who can access what — and what does that identity really need to do?
Enjoyed reading this content? Let the author know!
Your likes, comments, shares, and saves help creators reach more builders.
Loading recommendations
Loading article