Encryption Key Management

This component is responsible for creating cryptographically strong keys using approved random number generators or accepting externally generated keys via a Bring Your Own Key (BYOK) model. For vector databases, keys must be of sufficient strength (e.g., AES-256) to protect high-dimensional embeddings.

• Secure Entropy Source: Keys are derived from hardware-based random number generators to ensure unpredictability.
• Key Specification: Defines the algorithm, length, and intended use (e.g., data encryption, key wrapping).
• BYOK Workflow: Allows customers to import keys from their own Hardware Security Module (HSM), maintaining control over the root of trust.

This involves the persistent, encrypted storage of keys, ensuring they are never exposed in plaintext outside of secure, tamper-resistant environments. The master key, which protects all other keys, is often stored in a Hardware Security Module (HSM) or a Trusted Execution Environment (TEE).

• Key Wrapping: Data encryption keys are themselves encrypted by a master key before storage, creating a key hierarchy.
• HSM Integration: Provides FIPS 140-2 Level 3 validated physical security for root keys.
• Cloud KMS: Managed services like AWS KMS, Azure Key Vault, or Google Cloud KMS provide durable, highly available storage with strict access policies.

This governs the automated policies for the entire existence of a key, from creation to destruction. For vector databases, this ensures encrypted indexes remain accessible while enforcing security compliance.

• Rotation: Automated, scheduled generation of new keys and re-encryption of data. Old keys are retained to decrypt legacy data.
• Suspension/Revocation: Immediate disablement of a key if compromised, preventing its use for new encryption operations.
• Deletion/Destruction: Secure, irreversible eradication of key material, rendering all data encrypted by it permanently inaccessible (crypto-shredding).

This component defines and enforces who and what can use keys and for which purposes. It integrates with Identity and Access Management (IAM) systems to implement least privilege access.

• Policy Engine: Rules that specify which users, roles, or services can perform actions like Encrypt, Decrypt, or GenerateDataKey.
• Audit Integration: All key usage requests and policy decisions are logged to an immutable audit trail.
• Purpose Binding: Keys can be restricted to specific operations, e.g., a key may only be used to decrypt vectors from a specific collection.

This is the functional interface through which the vector database or client applications request cryptographic services. The KMS performs operations without exporting plaintext keys, a principle known as "wrap/encrypt in the KMS."

• Envelope Encryption: The KMS generates a data encryption key (DEK), returns it in encrypted form (wrapped), and the client uses it locally.
• Server-Side Decryption: For encrypted search, the KMS may securely decrypt query vectors within its boundary for processing.
• Standardized APIs: Supports interfaces like PKCS#11, KMIP, or cloud-native APIs (e.g., AWS KMS GenerateDataKey).

This component provides an immutable record of all security-relevant events within the KMS, which is critical for forensic analysis, regulatory compliance (e.g., GDPR, HIPAA, SOC 2), and demonstrating algorithmic trust.

• Comprehensive Logs: Records key creation, usage, rotation, deletion, and all access attempts (successful and denied).
• Integrity Protection: Logs are cryptographically signed or streamed to a secure Security Information and Event Management (SIEM) system.
• Key Usage Reporting: Provides attestation reports showing which keys protected which data assets, crucial for data sovereignty mandates.

Bring Your Own Key (BYOK) is a cloud security model where a customer generates and maintains ultimate control over their encryption keys in their own HSM or KMS, then securely transfers a copy to the cloud provider (e.g., vector database vendor) for data encryption.

• Customer Sovereignty: The customer retains the ability to revoke the key, instantly rendering data in the cloud unreadable.
• Compliance: Meets stringent regulatory requirements where the cloud provider must not hold the root key material.
• Process: Involves creating a key in the customer's HSM, wrapping it with a key exchange key, and importing the wrapped key into the cloud provider's KMS.

This two-tiered key hierarchy is the standard model for efficient encryption key management.

• Data Encryption Key (DEK): A symmetric key (e.g., AES-256) that directly encrypts vector data and indexes. DEKs are generated per dataset or segment and are stored alongside the data they encrypt.
• Key Encryption Key (KEK): A master key (often an RSA or AES key) stored in a KMS or HSM that is used to encrypt the DEKs. Only the encrypted DEKs are stored in the database.

This separation allows for efficient key rotation: only the KEK-encrypted DEK needs re-encryption when the master key changes, not the entire dataset.

Key Rotation is the scheduled, cryptographic process of retiring an existing encryption key and generating a new one to replace it. This limits the amount of data protected by any single key and is a core requirement of standards like PCI DSS.

• Automatic vs. Manual: Can be automated on a schedule (e.g., every 90 days) or triggered manually in response to a security incident.
• Re-Encryption: In a DEK/KEK model, rotating the master KEK only requires decrypting and re-encrypting the DEKs, not the petabytes of vector data.
• Key Versioning: Systems maintain metadata linking data to the specific key version used to encrypt it, ensuring old data can still be decrypted with archived keys.

Key Lifecycle Management is the comprehensive administration of a cryptographic key from its creation to destruction, encompassing all stages within encryption key management.

Core lifecycle states include:

• Generation: Creating a cryptographically strong key in a secure environment (HSM/KMS).
• Activation: Enabling the key for use in encryption operations.
• Suspension/Revocation: Temporarily or permanently disabling a key, often in response to suspected compromise.
• Archival: Securely storing retired keys for decrypting historical data.
• Destruction: Permanently deleting all copies of a key, rendering data encrypted with it irrecoverable.

Automated policy enforcement for these states is critical for vector database compliance.