Hello, I am currently experimenting with the re-encryption in a multi party setup using CKKS scheme, the idea is to re-encrypt the ciphertext which was encrypted using the shared public key. The setup is the following: Parties 1 and 2 and their corresponding secret shares of key pairs kp1 and kp2 …

@mpuskaric Sounds like your issue/question was resolved based on your edit? I might be wrong. Can you confirm if that’s the case and if not I’ll float it to other members to see if they can help

@iquah Thanks for the feedback, the issue regarding re-encryption has been resolved with the follow-up part. However, I’m still wondering whether it is possible to perform a re-encryption process in the same way as a multi-party decryption, where each party computes a partial re-encryption, and fu…

Would you mind making a new post for that question? That way it’ll ping the relevant people from the openfhe team :slight_smile: Thank you!

@mpuskaric Could you clarify which of the following two scenarios you are asking about? Do re-encryption only (without refreshing the noise - switch from the shared key to another key) Do interactive bootstrapping (reset the noise and do key switching).

@ypolyakov I actually had the first scenario in mind when I wrote the post. Thanks

Hi @mpuskaric Theoretically it is possible to do re-encryption using secret shares, but this is not currently supported by OpenFHE. I am wondering why you prefer this approach over proxy re-encryption. In the PRE case, the distributed process is needed only during the generation of the re-encrypti…

thanks @ypolyakov for the clarification. I was trying to implement a workflow for the distributed re-encryption key generation, but so far without success. In case of a multi party setup, where KeyPair1 and KeyPair2 are used for generating shared keys, how the workflow for generating the re-encrypt…

I believe you are asking about MultiAddEvalKeys. This function adds two evaluation keys, where the first polynomials are the same, and the second ones get added. Please search for examples with MultiAddEvalKeys, e.g., in threshold-fhe.cpp

Hi, In threshold-fhe.cpp, party A generates key pair with KeyGen() then the other party uses MultipartyKeyGen(patyA.publickey) for generating joint public key . Can i run KeyGen() algorithm for all party and then generate joint public key? I read the documantation but i could not find. I tried th…

Collective key switching

Library Questions

Caesar February 15, 2023, 1:46pm 11

The example in this post should help you achieve what you want.

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Collective key switching

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