End of support notice: On May 20, 2026, Amazon will end support for Amazon IoT Events. After May 20, 2026, you will no longer be able to access the Amazon IoT Events console or Amazon IoT Events resources. For more information, see [Amazon IoT Events end of support](https://docs.amazonaws.cn/iotevents/latest/developerguide/iotevents-end-of-support.html).

# Authenticating with identities
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Authentication is how you sign in to Amazon using your identity credentials. You must be authenticated as the Amazon Web Services account root user, an IAM user, or by assuming an IAM role.

For programmatic access, Amazon provides an SDK and CLI to cryptographically sign requests. For more information, see [Amazon Signature Version 4 for API requests](https://docs.amazonaws.cn/IAM/latest/UserGuide/reference_sigv.html) in the *IAM User Guide*.

## Amazon Web Services account root user
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 When you create an Amazon Web Services account, you begin with one sign-in identity called the Amazon Web Services account *root user* that has complete access to all Amazon Web Services services and resources. We strongly recommend that you don't use the root user for everyday tasks. For tasks that require root user credentials, see [Tasks that require root user credentials](https://docs.amazonaws.cn/IAM/latest/UserGuide/id_root-user.html#root-user-tasks) in the *IAM User Guide*. 

## IAM users and groups
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An *[IAM user](https://docs.amazonaws.cn/IAM/latest/UserGuide/id_users.html)* is an identity with specific permissions for a single person or application. We recommend using temporary credentials instead of IAM users with long-term credentials. For more information, see [Require human users to use federation with an identity provider to access Amazon using temporary credentials](https://docs.amazonaws.cn/IAM/latest/UserGuide/best-practices.html#bp-users-federation-idp) in the *IAM User Guide*.

An [https://docs.amazonaws.cn/IAM/latest/UserGuide/id_groups.html](https://docs.amazonaws.cn/IAM/latest/UserGuide/id_groups.html) specifies a collection of IAM users and makes permissions easier to manage for large sets of users. For more information, see [Use cases for IAM users](https://docs.amazonaws.cn/IAM/latest/UserGuide/gs-identities-iam-users.html) in the *IAM User Guide*.

## IAM roles
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An *[IAM role](https://docs.amazonaws.cn/IAM/latest/UserGuide/id_roles.html)* is an identity with specific permissions that provides temporary credentials. You can assume a role by [switching from a user to an IAM role (console)](https://docs.amazonaws.cn/IAM/latest/UserGuide/id_roles_use_switch-role-console.html) or by calling an Amazon CLI or Amazon API operation. For more information, see [Methods to assume a role](https://docs.amazonaws.cn/IAM/latest/UserGuide/id_roles_manage-assume.html) in the *IAM User Guide*.

IAM roles are useful for federated user access, temporary IAM user permissions, cross-account access, cross-service access, and applications running on Amazon EC2. For more information, see [Cross account resource access in IAM](https://docs.amazonaws.cn/IAM/latest/UserGuide/access_policies-cross-account-resource-access.html) in the *IAM User Guide*.