Batch and multivalue bootstrapping

Zama TFHE-rs
1

I have been following TFHE for some time now. I would really like to know if the latest version of tfhe-rs supports batch and multivalue bootstrapping. If I remember correctly, there was an idea about multivalue bootstrapping in first papers of TFHE, but it was for binary coefficients, has it been implemented for FheUint8 and so data structures?

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hello @divyesh we now have added the many lut PBS allowing to evaluate several functions on a single input if you have some MSB in the message that are unused

See e.g. ServerKey in tfhe::shortint::server_key - Rust

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This is good. I am actually asking about whether it is possible to perform same look up table evaluation on multiple inputs using single bootstrap function

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We do not have that at the moment, we were thinking about doing a batch PBS potentially

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If I want to do a batch bootstrap, how should I proceed, do I need to make changes in source code? Correct me if I am wrong, one idea that I have is packing multiple LWE ciphers using a TLWE cipher and apply bootstrap on TLWE. Am I correct in thinking it this way?

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how would the packing and PBS work ?

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This is something I have been thinking for some time for which I currently don’t have an answer

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The reason I ask @divyesh is because we do not have code for bootstrapping a GLWE with TFHE-rs, we can bootstrap an LWE with an auxiliary GLWE but not a GLWE itself

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I understand that. Can you give a sample code on doing PBS with auxiliary GLWE cipher?

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sorry what I meant is the auxiliary GLWE is the Lookup Table you are used to

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