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LoganDarkyesterday at 4:42 PM2 repliesview on HN

One flaw with FHE is that it guarantees only that you need the key to see the inputs or outputs of the computation, but not necessarily that the computation is the one you want. For example, the computation could be adversarial for certain inputs, or an adversary could insert their own computation first (or last).


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noman-landyesterday at 4:58 PM

100% not an expert but my understanding was that part of what you are proving by signing the computation is that the computation itself was performed specifically as agreed to. I may be mixing this up with zero knowledge proofs.

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mswphdyesterday at 7:17 PM

note that this is even true for an honest server. Roughly, FHE computations often require certain bounds on the (encrypted) messages for things like tuning polynomial approximation domains etc. If your messages are out of distribution for the tuned polynomial approximations you'll get back garbage as as result.