Federated Access in AWS: Streamlining User Management and Security

Introduction

Amazon Web Services (AWS) offers a wide range of cloud-based computing services and tools to businesses and organizations of all sizes. These services include virtual servers, storage, databases, analytics, and more. However, managing access to these resources can be challenging, particularly if you have many users or are using multiple AWS accounts.

One approach to simplifying user access management is through the use of federated access. This method enables users from an external identity provider (IdP) to access AWS resources without requiring a separate AWS Identity and Access Management (IAM) user account. Instead, federated access leverages the user’s existing corporate credentials, reducing the administrative overhead of managing multiple sets of credentials for each user.

This article will explain how federated access works in AWS and explore its benefits and use cases.

Understanding Federated Access in AWS

At its core, federated access enables users to access AWS resources using their existing corporate credentials. This approach streamlines user management by using a single, centralized source of identity and authentication.

Organizations like Microsoft Active Directory, Okta, or Google Workspace, typically use a SAML 2.0-compliant identity provider to enable federated access. These providers authenticate users and issue a SAML assertion containing the user’s identity and group membership information.

Once the user presents the SAML assertion to AWS Security Token Service (STS), STS validates the assertion and generates temporary AWS security credentials. These credentials have been granted permissions based on the user’s group membership and the associated IAM roles and policies.

Let’s take a closer look at the process of federated access in AWS:

Step 1: The user attempts to access an AWS resource. The process begins when a user attempts to access an AWS resource, such as the AWS Management Console or an API. First, the user is redirected to their organization’s identity provider (IdP) to authenticate using their existing corporate credentials.

Step 2: IdP issues a SAML assertion. After successful authentication, the IdP issues a SAML assertion containing the user’s identity and group membership information. This assertion is digitally signed and encrypted to ensure its authenticity and integrity.

Step 3: User presents SAML assertion to AWS STS. The user presents the SAML assertion to AWS Security Token Service (STS), which validates the assertion and generates temporary AWS security credentials. These credentials include an access key, a secret access key, and a security token. The security token has a limited lifetime, typically 15 minutes to 1 hour.

Step 4: The user accesses AWS resources using temporary security credentials. The user can now access the AWS resource using the temporary security credentials. These credentials have been granted permissions based on the user’s group membership and the associated IAM roles and policies. Once the security token expires, the user must obtain a new token to continue accessing the resource.

Benefits of Federated Access in AWS

Federated access offers several benefits to organizations, including:

1. Centralized User Management: Federated access enables organizations to manage user permissions centrally, using their existing identity provider. This approach eliminates the need for separate IAM user accounts for each user, simplifying user management and reducing administrative overhead.
2. Improved Security: Federated access provides enhanced security by enforcing organizational authentication policies. For example, an organization can require multi-factor authentication (MFA) for all users accessing AWS resources, regardless of location or device.
3. Seamless Access to AWS Resources: Federated access enables users to access AWS resources seamlessly using their existing corporate credentials. This approach reduces the need for users to remember and manage multiple sets of credentials, improving the user experience and reducing the risk of credential theft.
4. Reduced Risk of Human Error: Federated access reduces the risk of human error by eliminating the need for users to manage multiple sets of credentials. This approach reduces the risk of accidental exposure of sensitive information, such as passwords or access keys.

Use Cases for Federated Access in AWS

Federated access benefits organizations with multiple AWS accounts, large numbers of users, or complex permission structures. Here are some everyday use cases for federated access in AWS:

1. Enterprise Organizations: Large enterprises typically have complex permission structures and multiple AWS accounts. Federated access enables these organizations to manage user permissions centrally, using their existing identity provider.
2. Multi-Account Environments: Organizations that use multiple AWS accounts for different use cases, such as development, testing, and production, can use federated access to streamline user access management across accounts.
3. Partner and Customer Access: Organizations that provide AWS resources to partners or customers can use federated access to enable these users to access resources using their existing corporate credentials. This approach simplifies user management and reduces the risk of credential theft.
4. Temporary Workers: Organizations that hire temporary workers or contractors can use federated access to provide these users with temporary access to AWS resources without needing separate IAM user accounts.

Conclusion

Federated access is a powerful tool for simplifying user access management and improving security in AWS. By leveraging existing corporate credentials, federated access enables organizations to manage user permissions centrally, streamline user access management, and reduce the risk of credential theft. If you’re using AWS and managing large numbers of users, federated access is worth considering to simplify your user management and improve your security posture.