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AWS IAM Policies SAP C02 exam prep #2

Hello Cloud learners,

Hope everyone is doing good.

Here is next post on my SAP C02 preparation study notes. (Check here my previous post here)

We have already discussed about AWS organizations, now in this post let's go through different IAM Policies with some real time scenarios.

Identity Policies:

IAM Identity Policies are JSON documents that define permissions for individual IAM users or roles. These policies determine what actions are allowed or denied on AWS resources.

Real-time use case: IAM Identity Policies are used to grant fine-grained permissions to individual identities based on their specific needs and roles within an organization.
Real-world example: Consider an organization with a group of administrators responsible for managing EC2 instances. An IAM Identity Policy can be created and attached to this group, specifying permissions to start, stop, and terminate EC2 instances.

Resource-Based Policies:

Resource-Based Policies are IAM policies that are attached directly to AWS resources, such as S3 buckets, Lambda functions, or SQS queues. They control access to the resource itself and can be used to grant permissions to other AWS identities.

Real-time use case: Resource-Based Policies are commonly used to grant cross-account access to resources or enable third-party services to access specific AWS resources securely.
Real-world example: Suppose you have an S3 bucket that contains publicly accessible files. You can create a resource-based policy that allows a specific IAM user from another AWS account to access and read objects from that bucket.
AWS IAM Permission Boundaries Policies:

Permission Boundaries:
Permission Boundaries Policies define the maximum permissions that can be applied to an IAM entity (user or group). They help prevent unauthorized escalation of privileges by limiting the permissions that can be granted.

Real-time use case: Permission Boundaries Policies are useful in scenarios where you want to assign specific permissions to users or groups while ensuring they cannot exceed a certain level of access.
Real-world example: Consider a situation where you have a team of developers working on different projects. You can set a permission boundary policy to restrict their permissions to only the resources required for their respective projects, preventing them from accessing other sensitive resources.

Service Control Policies (SCPs)
Service Control Policies (SCPs) are a type of policy used in AWS Organizations to set fine-grained permissions across multiple AWS accounts. SCPs are used to establish common security and compliance controls at the organization level.

Real-time use case: SCPs are particularly useful in large organizations or multi-account environments, where you need to enforce consistent policies and restrict access to certain services or actions across multiple AWS accounts.
Real-world example: Let's say you have an AWS Organization with multiple accounts, including development, testing, and production. You can create an SCP that denies access to specific services, such as deleting EC2 instances, across all accounts, ensuring consistent security practices.


  • Identity policies are attached directly to IAM users or roles, while resource-based policies are attached directly to AWS resources.
  • Permission boundaries policies limit the maximum permissions that can be granted to an IAM entity, while resource-based policies and identity policies define the permissions for accessing specific resources.
  • Service control policies (SCPs) are used at the organizational level to set fine-grained permissions across multiple AWS accounts, while identity policies, resource-based policies, and permission boundaries policies are used at the individual or resource level

Overall, these different policy types in AWS IAM provide various levels of control and flexibility for managing access to AWS resources, ensuring security, and enforcing compliance within organizations and across accounts.

Complete AWS documentation

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Top comments (1)

justplegend profile image

Thanks! :)