What is an IAM role in AWS?

An IAM role in AWS is an identity with specific permissions that determine what actions are allowed on designated resources. Unlike a user, a role is not associated with a single person; instead, it can be assumed by anyone who needs it, such as AWS services, applications, or even external users. This capability allows for a greater level of security and flexibility, as roles can be assigned and revoked dynamically as needs change.

IAM roles are crucial for scenarios like AWS Lambda functions needing access to S3 buckets or EC2 instances requiring permissions to interact with other AWS resources. By utilizing roles, AWS enables a separation between users and their permissions, promoting least privilege access and enhancing overall security.

In contrast, groups of users primarily facilitate the organization of permissions across multiple individuals rather than providing specific access control linked to the task at hand. Encryption keys serve an entirely different purpose, focusing on data security rather than user permissions. Network access policies relate to controlling network traffic rather than defining user identity and permissions within AWS resources. Thus, the defining feature of IAM roles as specific permissions associated with identities is the reason why this option is the most accurate representation of what an IAM role is.