Two independent healthcare institutions want to collaborate by training a shared predictive machine learning model using their respective proprietary clinical datasets. The collaboration has the following strict security and governance requirements: Neither organization is permitted to expose raw data or cryptographic decryption keys to the other party. The infrastructure administrator executing the workload must not be able to view data in use in memory, access the underlying operating system, or extract intermediate computation states. Decryption keys stored in Cloud Key Management Service (Cloud KMS) must be released dynamically only after cryptographically verifying the identity, boot measurements, and container image digest of the executing workload. Which Google Cloud Confidential Computing solution should be implemented to support this multi-party collaboration?

Confidential Space: ### What Confidential Space is **Confidential Space** is Google Cloud's confidential computing solution designed specifically for secure multi-party data collaboration and privacy-preserving analytics. It builds on hardware-based **Trusted Execution Environments (TEEs)** using **AMD SEV-SNP** or **Intel TDX** to allow multiple parties to share and process sensitive data without disclosing raw data to each other or to the workload operator. ### How it meets the requirements - **Multi-party confidentiality:** Confidential Space runs a specialized, hardened, minimal container operating system that blocks interactive operator access (disabling SSH, interactive logins, and remote kernel debugging). Neither the workload host nor the contributing organizations can inspect memory or data in use. - **Cryptographic attestation:** The environment generates a hardware-rooted **attestation token** containing cryptographic measurements of the platform, the unmodified boot environment, and the container image hash. - **Attestation-based key release:** Using **Workload Identity Federation** and Cloud KMS attribute conditions, Cloud KMS inspects the attestation claims provided by the Google Cloud Attestation Service and releases decryption keys exclusively if the running container image matches the pre-approved code hash. ### Key advantages and capabilities - **Zero operator trust:** Enforces strict execution integrity by preventing root or infrastructure admins from accessing running memory. - **Hardware-enforced memory encryption:** Protects data in use from hypervisor inspection and co-located workloads. - **Declarative trust policies:** Allows data owners to define granular IAM conditions based on exact code image digests and provenance. - **Built-in attestation client:** Automates token exchange and token validation workflows with Cloud KMS and storage buckets. ### Why this is optimal Unlike general-purpose Confidential VMs or GKE Nodes, **Confidential Space** is purpose-built to solve the mutual distrust dilemma in multi-party analytics by eliminating administrative OS access and enforcing hardware-attested code execution before releasing sensitive cryptographic keys.