One of my greatest goals has always been to write/produce useful content that will help software developers and other personnel in the software development ecosystem in their careers and learning journeys. This article is the first of a series of articles on Cloud Computing in AWS. Be on the lookout for future articles in this series. The topic with which we are concerned today is AWS IAM. Like other AWS and cloud computing concepts and services, IAM can be a little tricky to understand and use for most people especially beginners specifically those coming from a non-computing background. The purpose of this article is to help you understand what IAM is, look at IAM-related terminologies and some IAM best practices, so ride with me, and let's get started.

What is Identity and Access Management?

AWS Identity and Access Management (IAM) is a service provided by AWS that allows you to manage user access to your AWS resources. It lets you create and manage user accounts, grant permissions, and define policies that determine what actions a user can perform on your AWS resources.

To put things into perspective, let's look at it this way. IAM is like a bouncer at a club, carefully examining every person who wants to go in and determining whether they have the right credentials to get in. Just like a bouncer ensures that only authorized people are allowed into the club, IAM ensures that only authorized users are allowed to access your AWS resources.

Think of IAM as a security guard for your AWS resources, like a watchful eagle perched high in the sky, keeping a keen eye on every user who wants to access your resources. IAM helps you create and manage user accounts, define permissions, and enforce policies to protect your resources from unauthorized access.

Some IAM terminologies

User — A user is an entity that represents a person or service that interacts with your AWS resources. A user can have a unique name and security credentials, such as a password or access keys, that are used to authenticate and authorize access to AWS resources. When you create a user in IAM, you can assign specific permissions to that user to control what actions they can perform on AWS resources. For example, you might create a user with permission to access a relational database but restrict their ability to modify or delete tables in that database. IAM users can also be organized into groups to facilitate the management of permissions. For example, you might create a group called "Developers" and add IAM users to that group who require the same set of permissions for their development work. IAM users are a fundamental component of AWS IAM that enable you to control access to your AWS resources by defining unique security credentials and permissions for each user.

Group — A group is a collection of user accounts that share similar permissions. Instead of assigning permissions to each user individually, you can create a group and assign permissions to the group. This makes it easier to manage user access to your AWS resources, especially if you have many users who need similar levels of access. Think of a group as a team of superheroes, each with their unique abilities and powers. Just like a superhero team works together to save the day, a group in IAM allows you to assign permissions to a team of users who need similar levels of access to your AWS resources. For instance, imagine you have a team of developers who all need access to your database. Rather than assigning permissions to each developer individually, you can create a group called "db-devs" and assign permissions to that group. Then you can add each developer you would like to have database access to the group, and they will inherit the permissions of the group. Overall, a group in IAM is a useful tool for managing user access to your AWS resources, making it easier to assign and revoke permissions, and ensuring that users have only the access they need.

Role — A role refers to a set of permissions that you can temporarily assign to someone or something. Unlike users and groups, roles are not associated with a specific entity. Instead, they can be assumed by trusted parties such as AWS services or users outside of your AWS account. Think of a role as a special costume that a superhero can wear to gain temporary powers. Just like a superhero can wear a costume to gain special abilities, a role allows an entity to temporarily gain permissions that it wouldn't normally have. To conclude, roles are a useful tool for assigning temporary permissions to entities, making it easier to manage access to your AWS resources and helping you enforce the rule of least privilege which states that users, groups, and roles should be granted only the permissions that they need to do their jobs and no more.

IAM Policies — In AWS IAM, a policy is a set of rules that defines what actions are allowed or denied on AWS resources. Policies are attached to IAM identities, such as users, groups, and roles, and they determine the level of access that each identity has to AWS resources. IAM policies are written in a language called the AWS policy language, which is a JSON-based language that defines permissions in a structured way. Each policy consists of one or more statements and each statement has a set of conditions that define when the statement applies and a set of actions that are allowed or denied. Below is an example of an IAM policy;

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "s3:GetObject",
                "s3:GetObjectVersion"
            ],
            "Resource": "arn:aws:s3:::example-bucket/*"
        },
        {
            "Effect": "Deny",
            "Action": [
                "s3:DeleteObject",
                "s3:DeleteObjectVersion"
            ],
            "Resource": "arn:aws:s3:::example-bucket/*"
        }
    ]
}

IAM policies are a powerful tool for managing access to AWS resources and can be used to enforce the principle of least privilege. By creating policies that allow only the necessary actions for each IAM entity, you can reduce the risk of unauthorized access to your resources. They are a critical part of IAM that enable you to define granular permissions for each IAM identity and control access to your AWS resources.

IAM Best Practices

Now it's time for us to talk about some best practices that will help you use IAM to effectively control access to your AWS resources.

1. Use IAM groups to manage permissions: Instead of assigning permissions directly to individual IAM users, it's better to group users with similar job functions and assign permissions to the group instead. This makes it easier to manage permissions and makes it more efficient to revoke or modify permissions when the need for that arises.

2. Regularly review and audit IAM policies: It's important to regularly review and audit IAM policies to ensure that they are still relevant and appropriate. This helps to identify any unnecessary or overly permissive policies that could be a security risk.

3. Enable multi-factor authentication (MFA): MFA adds an extra layer of security to IAM user accounts by requiring an additional verification step, such as a text message or a one-time access code from an authentication app when signing in. This helps to prevent unauthorized access to your account.

4. Use the principle of least privilege: This means that you should only give IAM users the minimum level of access required to perform their job duties. This helps to reduce the risk of accidental or intentional misuse of resources.

5. Rotate access keys regularly: IAM access keys are used to authenticate API requests to AWS services. By rotating these keys regularly, you can reduce the risk of an attacker gaining access to your resources.

These best practices are important for securing your AWS resources and keeping your account safe. By following them, you can help ensure that IAM users have the appropriate level of access and that your account is protected from unauthorized access.

Conclusion

IAM is a powerful service that helps you manage access to your AWS resources. With the use of IAM, you can create and manage IAM users and groups, and assign them appropriate permissions to access and use your AWS resources. IAM policies play a critical role in granting or restricting access to specific resources or actions. Following IAM best practices will ensure that your AWS environment is secure and that you are only granting the necessary permissions to your users. With the knowledge gained from this article, you are now equipped to get started with IAM and take your first steps towards building a secure and efficient AWS environment. We didn't look at how to create users, roles or permissions in the AWS management console but if you'd like to go a step further to see how it is done, check out this guide by AWS or if you prefer video content, check out this youtube video. Thank you for your time, be sure to leave any questions you have in the comments section.