Identity and Access Management (IAM)

Identity and Access Management (IAM) is the nervous system of cloud security. It provides the mechanism to control 'who' (authentication) can do 'what' (authorization) with your cloud resources. The core components of IAM are principals, policies, and resources. A 'principal' is an entity that can perform actions; this can be a human 'user', a 'group' of users, or a 'role' that cloud services or applications can assume temporarily. For example, you can create an IAM user for a developer on your team. You can then organize multiple developers into a 'developers' group. A 'role' is a powerful concept used to delegate access without sharing long-term credentials. For instance, a virtual machine might need to read files from an object storage bucket. Instead of hardcoding access keys into the VM, you can assign it an IAM role that grants the necessary read permissions. Access is granted via 'policies', which are JSON documents that explicitly define permissions. A policy might state 'Allow user Bob to perform the ec2:StartInstances action on instance i-12345'. By attaching policies to users, groups, and roles, you can enforce the principle of least privilege, ensuring that each entity has only the minimum permissions required to perform its function. This granular control is fundamental to preventing unauthorized access and securing your cloud environment.