AWS IAM Core Concepts: Understanding Identity and Access Management
Published: 2023-02-18 23:28:12

# AWS IAM Core Concepts

AWS Identity and Access Management (IAM) is a service that allows you to manage access to AWS resources. It enables you to create and manage AWS users and groups, as well as define permissions that allow or deny access to specific resources.

## Key Concepts

### Users

An IAM user is an identity within your AWS account that you can use to securely access your resources. You can create and manage multiple users within your account and control their access to resources.

### Groups

An IAM group is a collection of IAM users. You can use groups to specify permissions for a set of users, making it easier to manage their access to resources. 

### Roles

An IAM role is an AWS identity that you can create in your account that has specific permissions. You can assume a role to temporarily take on the permissions assigned to the role. This is useful for granting access to resources to services or applications that run on AWS.

### Policies

An IAM policy is a set of permissions that you can attach to an IAM user, group, or role. A policy defines what actions are allowed or denied on specific resources.

## Best Practices

Here are some best practices to follow when working with AWS IAM:

- Use unique and strong passwords for IAM users.
- Use IAM groups to manage permissions for multiple users.
- Follow the principle of least privilege, giving users only the permissions they need to perform their tasks.
- Use IAM roles to grant access to resources for services or applications.
- Regularly review and rotate access keys for IAM users to ensure security.

## Analogies to help you more understand things.

1. Imagine you are the owner of a company with multiple departments, and each department has specific job roles with different levels of access to company resources.

IAM users can be thought of as individual employees, each with their own unique login credentials and permissions. Users have access to only the resources that the owner has explicitly granted them access to.

IAM roles can be thought of as job titles that define a set of responsibilities and permissions that are necessary to perform a particular job function. For example, a "manager" role might have access to all employee files, while a "salesperson" role might have access only to customer data.

IAM groups can be thought of as teams of employees who have similar job functions or permissions. For example, a "marketing" group might have access to marketing materials, while an "engineering" group might have access to source code.

Managed policies can be thought of as company policies that are standardized across all departments. These policies define rules for access to company resources and are managed centrally by the owner. For example, a "security" policy might require that all users enable multi-factor authentication, while a "compliance" policy might require that all employees complete regular training.

In summary, IAM roles, users, groups, and managed policies work together to ensure that employees have access only to the resources they need to do their jobs, while the owner maintains control and oversight over all company resources.

2. Imagine a university with various buildings and rooms, and each room has a different level of access control. The university's security team needs to manage who has access to each room.

IAM Users are like individual students, each with their own unique ID and access to certain rooms. Users have their own login credentials and can be granted access to specific resources, such as EC2 instances or S3 buckets.

IAM Groups are like student clubs, with multiple users who share similar access needs. The security team can create groups based on specific permissions or job roles, and then assign users to those groups. This makes it easier to manage permissions for multiple users at once, rather than having to manage them individually.

IAM Roles are like temporary visitor badges. They are created to provide temporary access to resources to users or AWS services without the need to create an IAM user. For example, an EC2 instance can be assigned an IAM role, which allows it to access specific resources for a set amount of time.

Managed Policies are like the university's access control policy, which is defined by the security team. The policy determines which rooms can be accessed by which users or groups, and what actions they can take within those rooms. Similarly, a managed policy in IAM is a set of permissions that can be assigned to multiple users, groups, or roles. It simplifies permission management and ensures consistent access control across your organization.

## Conclusion

AWS IAM is a powerful service that allows you to manage access to your AWS resources. By following the key concepts and best practices outlined above, you can ensure that your resources are secure and your users have the appropriate level of access.