Hello Everyone, I have a usecase for OpenFHE, where I need plaintext-matrix A with ciphertext-vector v multiplication. I implemented this via the giant-step, baby-step method with A.v = \sum_{k=0}^{n_2-1} \mathrm{Rot} \left( \sum_{j=0}^{n_1-1} \mathrm{Rot}\left(diag(A, kn_1 + j), -kn_1\right) \cdo…

Hi @LHenke This issue is expected. For the setting you described, you would need n_1 + n_2 - 2 rotation keys. Theoretically speaking, you can reduce the number of rotation keys by applying the baby-step-giant-step key switching procedure in a hierarchical manner. In other words, the inner loop can…

Does the memory usage scale linearly? So is there a way to estimate how much memory one has to use beforehand?

Size of Rotation keys

FHE Questions

ypolyakov May 5, 2023, 3:45pm 4

See the key estimates at Bootstrapping AutomorphismKey keys exceeds maximum protobuf size of 2GB

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Size of Rotation keys

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