# Migrating from AWS CloudHSM Client SDK 3 to Client SDK 5
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In AWS CloudHSM, customer applications perform cryptographic operations using the AWS CloudHSM Client Software Development Kit (SDK). Client SDK 5 is the primary SDK that continues to have new features and platform support added to it.

Client SDK 3 includes two separate command line tools: the CMU for managing users and the KMU for managing keys and performing operations with keys. Client SDK 5 consolidates the functions of the CMU and KMU (tools that were offered with Client SDK 3) into a single tool, the [AWS CloudHSM Command Line Interface (CLI)](cloudhsm_cli.md). User management operations can be found under the subcommands [The user category in CloudHSM CLI](cloudhsm_cli-user.md) and [The quorum category in CloudHSM CLI](cloudhsm_cli-qm.md). Key management operations can be found under the [key subcommand](cloudhsm_cli-key.md), and cryptographic operations can be found under the [crypto subcommand](cloudhsm_cli-crypto.md). See [Reference for CloudHSM CLI commands](cloudhsm_cli-reference.md) for a complete list of commands.

For benefits on migrating, see [Benefits of AWS CloudHSM Client SDK 5](client-sdk-5-benefits.md).

See the following topics for detailed instructions on migrating from Client SDK 3 to Client SDK 5. The latest version of AWS CloudHSM Client SDK is 5.16.
+ [Migrate your AWS CloudHSM PKCS \$111 library from Client SDK 3 to Client SDK 5](pkcs11-migrate-to-sdk-5.md)
+ [Migrate your OpenSSL Dynamic Engine from AWS CloudHSM Client SDK 3 to Client SDK 5](openssl-migrate-to-sdk-5.md)
+ [Migrate your Key Storage Provider (KSP) from AWS CloudHSM Client SDK 3 to Client SDK 5](ksp-migrate-to-sdk-5.md)
+ [Migrate your JCE provider from AWS CloudHSM Client SDK 3 to Client SDK 5](java-lib-migrate_to_sdk5.md)

For functionality or use cases that are not supported by CloudHSM CLI, contact [AWS Support](https://support.console.aws.amazon.com/support/home#/).