SA-9(6) - External System Services | Organization-controlled Cryptographic Keys

Maintain exclusive control of cryptographic keys for encrypted material stored or transmitted through an external system.


ID: SA-9(6)
Enhancement of : SA-9

Space Segment Guidance

When external system services are employed—perhaps a commercial ground station link or a cloud-based data processing service—controlling cryptographic keys in-house is essential for maintaining trust in an often-untrusted ecosystem. By generating, storing, and distributing keys strictly within the organization, space programs retain authority over how data is encrypted and decrypted at every stage. This approach can involve secure key distribution hardware, designated key custodians, and well-defined lifecycle management (e.g., periodic rotation and revocation). For high-assurance systems, keys must never be exposed in plaintext form to third-party providers. Additionally, contingencies must account for key compromise scenarios: should a ground station’s security controls be questioned, the organization can revoke those cryptographic credentials and push out new keys, thereby restricting external service providers to the bare minimum of privileged operations necessary to support mission objectives.