Identity Access Management

Users are considered those with an AWS Identity that can log in to the console. These identities are governed by policies which can be associated with a role or a group.

Groups do not sign in to the AWS Console, nor do roles; only users — those with an AWS Identity.

AWS Account w/ Root User
AWS IAM Users w/ Access to Resources inside AWS Account

Or, with an AWS Organization:

1. AWS Organization w/ Root Account
    - Roles that allow access to different nested-organizations or member-accounts
2. Member Organizations / Member Accounts
    - Can be restricted to only access certain resources

IAM Groups

Groups allow for policies to be associated with certain users as an admin construct.

A Group cannot be specified in an IAM Policy

IAM Roles

Utilizes Secure Token Service (STS) to generate temporary access keys which a “Trusted Entity” (ie, AWS Service, IAM User, Remote AWS Account) can use.

Roles are made up of two parts

    - Trusted Entity (*who*)
        - Other AWS Accounts
        - AWS Services
        - IAM Users
    - Security Policy (*what*)

When to Use an AWS Role vs Account

- Instead of creating 100s of users for every user that uses an application that accesses an AWS resource (IE, dynamodb table), give the application a role to access dynamo db
- Instead of creating 2K new users for company merger, create an IAM Role for that specific AWS Account.

AWS Organizations

Allows for associating multiple accounts together for consolidated billing as well as other features composed of (a) a Master Account, (b) Member Account, and (c) Nested Organizations called Organizational Units.

Financial Benefits

    - Sharing of reserved resources across accounts
    - Bulk usage discounts
    - Account level service permissions
        - Account X cannot access resource `Y`

Role Switching

Account A can access Account B w/ a single IAM User associated with the Organization through a STS Role, by convention called “OrganizationAccountAccessRole”.

When a new account is created, it is automatically give

Master Accounts

General best practices are to only use master account for:

- Handling billing of member-accounts
- Creating IAM Users
- Storing logs of resources

Service Control Policies

Account-Level Permissions:

- Inverse Tree w/ Inheritance
- Nested Organizations
- `Master Accounts` cannot be restricted from using any resources

Quick Facts

- 5K IAM Users per Account
- Unlimited roles; which can be assumed by an entity
- Cannot use a role to sign into the AWS Console.

#aws/associate/test-prep

Maxwell Kendall