Zero trust usually stops at the network: verify every request, trust no subnet. But in a shared cloud, the host operating system and the hypervisor can still read a tenant's memory. Confidential computing closes that last gap, and it is now practical for everyday workloads.
The gap that encryption at rest leaves open
Data is routinely encrypted on disk and in transit. While it is being processed, though, it sits in plain text in memory, where a compromised host or a privileged operator could in principle inspect it. For regulated workloads such as health records or payment data, that residual risk is often the final blocker to moving to a shared platform.
How hardware enclaves work
Modern server processors can run a virtual machine whose memory is encrypted with a key that never leaves the chip. The hypervisor still schedules the machine and gives it resources, but it sees only ciphertext. Even a full memory dump of the host reveals nothing useful.
Before any secret is released to the workload, the processor produces a signed attestation report describing exactly what firmware and code were loaded. Our key service checks that report against the expected measurements and only then hands over database credentials or decryption keys.
cirrolane deploy \ --confidential \ --attest-policy ./policy/prod.json \ --secrets vault://payments/prod
Zero trust that ends at the hypervisor is still trusting someone. Enclaves let us remove that last assumption.
What it costs in practice
Memory encryption adds a small cost to every memory access. Across our benchmark suite the overhead ranged from 2 to 6 per cent for web services and up to 11 per cent for memory-heavy analytics. For most teams that is a fair price for removing the host from the trust boundary.
- Enable confidential mode per service, not per account.
- Pin attestation policies in version control alongside code.
- Rotate secrets automatically when a new measurement is approved.
- Encryption at rest and in transit leaves data exposed while in use.
- Hardware enclaves encrypt memory with keys held inside the processor.
- Attestation ties secret release to verified code and firmware.
- Overhead is modest for most web and API workloads.