Research · 13 August 2026 · David Zheng

How we measure encrypted logic operations

An encrypted logic operation is one homomorphic step the Umbra runtime executes on ciphertext. Card figures count those steps per second on production silicon, with a fixed harness, to thermal steady state.

That is the 40,000,000 ops/s number on the Umbra U100. It is measured. It is not a node number.

Nodes

N4 and N8 figures multiply measured single-card throughput by card count. They are labelled estimated until end-to-end node measurement completes. Linear scaling with zero interconnect or host overhead is not assumed as fact: it is the estimate, and it is marked as such.

Two axes

Versus conventional lattice FHE, the operation-level gap is on the order of ~1000×. That comparison is about bootstrapping and noise, not about a full application.

Versus native computation, end-to-end overhead is ~50×. That comparison is what a production system costs relative to decrypting and running in the clear. The two figures never share a sentence.

Full methodology →