====== AWS Key Management Service (AWS KMS) ======
**AWS Key Management Service (AWS KMS)** is a managed cryptographic service provided by [[amazon|Amazon]] Web Services that enables organizations to create, control, and manage encryption keys used to protect data across AWS services and applications. AWS KMS integrates with various AWS services and third-party platforms to provide centralized key management, audit logging, and compliance capabilities for encryption operations.

===== Overview and Core Functionality =====
AWS KMS provides a secure, scalable solution for managing cryptographic keys without requiring organizations to build and maintain their own key management infrastructure. The service supports both **AWS-managed keys** (created and maintained by AWS) and **customer-managed keys (CMKs)**, which give organizations direct control over key creation, rotation, and access policies (([[https://docs.aws.amazon.com/kms/latest/developerguide/overview.html|AWS - AWS Key Management Service Developer Guide]]))

The service enables encryption of data at rest and in transit across multiple AWS services including Amazon S3, Amazon DynamoDB, Amazon RDS, and AWS Lambda. All cryptographic operations performed through AWS KMS are automatically logged in **AWS CloudTrail**, providing comprehensive audit trails for compliance and security monitoring purposes (([[https://docs.aws.amazon.com/kms/latest/developerguide/logging-using-cloudtrail.html|AWS - Logging AWS KMS API Calls with CloudTrail]]))

===== Customer-Managed Keys (CMKs) and Integration =====
Customer-Managed Keys represent a critical component of AWS KMS, allowing organizations to maintain full control over encryption key lifecycle management. CMKs can be created within AWS KMS and configured with specific key policies that define which principals can perform cryptographic operations. Organizations can reference CMKs using **Amazon Resource Names (ARNs)**, enabling integration with various applications and services through standardized identifiers (([[https://docs.aws.amazon.com/kms/latest/developerguide/concepts.html|AWS - AWS KMS Concepts and Terminology]]))

CMKs support integration with third-party platforms and applications. For example, organizations can configure data platforms to use CMKs stored in AWS KMS for encryption operations, with the platform referencing keys via their ARN identifiers. This integration approach enables centralized key management while allowing applications to leverage CMK functionality for protecting sensitive workloads (([[https://www.databricks.com/blog/take-control-customer-managed-keys-lakebase-postgres|Databricks - Take Control with Customer-Managed Keys in Lakebase with Postgres]]))

===== Security and Audit Capabilities =====
AWS KMS provides multiple layers of security controls and audit mechanisms. All key operations, including encryption, decryption, key rotation, and key policy modifications, are logged automatically in CloudTrail. These audit logs enable organizations to track key usage patterns, detect unauthorized access attempts, and maintain compliance with regulatory requirements such as HIPAA, SOX, PCI DSS, and GDPR (([[https://docs.aws.amazon.com/kms/latest/developerguide/logging-using-cloudtrail.html|AWS - AWS KMS Security and Compliance]]))

Key policies in AWS KMS follow the principle of least privilege, allowing administrators to grant specific permissions to individual users or services. The service supports **key rotation** policies, which automatically rotate CMK material at regular intervals to minimize the impact of potential key compromise. Additionally, AWS KMS separates key material storage from key management operations, ensuring that key material never leaves AWS HSM (Hardware Security Module) boundaries (([[https://docs.aws.amazon.com/kms/latest/developerguide/key-policies.html|AWS - Using Key Policies in AWS KMS]]))

===== Integration and Operational Considerations =====
Organizations implementing AWS KMS should consider factors including key retention policies, cross-region replication requirements, and integration complexity with existing infrastructure. CMK usage incurs per-request charges in addition to AWS KMS service fees, which organizations should factor into cost planning. The service supports key import functionality, allowing organizations to bring existing keys into AWS KMS for centralized management (([[https://docs.aws.amazon.com/kms/latest/developerguide/importing-keys.html|AWS - Importing Key Material in AWS KMS]]))

For organizations operating across multiple AWS regions, AWS KMS supports multi-region keys that simplify key management and enable regional disaster recovery capabilities. The service integrates with AWS Identity and Access Management (IAM) for [[fine_grained_access_control|fine-grained access control]] and with AWS Organizations for policy-based key governance across multiple accounts (([[https://docs.aws.amazon.com/kms/latest/developerguide/multi-region-keys-overview.html|AWS - Multi-Region Keys in AWS KMS]]))


===== See Also =====

  * [[google_cloud_kms|Google Cloud Key Management Service (Google Cloud KMS)]]
  * [[amazon_web_services_aws|Amazon Web Services (AWS)]]
  * [[aws_rds|AWS RDS]]
  * [[customer_managed_keys_cmk|Customer Managed Keys (CMK)]]
  * [[databricks_key_manager_service|Databricks Key Manager Service]]

===== References =====