Hi,

I’m curious to know about the maximum modulus for plaintext in a single LWE ciphertext. Could you provide insight into the expansion factor associated with this modulus?

I see that concrete support up to 16b. Is that 16 bit encrypted into one LWE or multiple?

Hi,

Support for 16bits TLU is not done directly. It uses CRT representation where multiple ciphertext of smaller modulus are combined to form a logical ciphertext of bigger modulus.

Hi, Thanks for the reply.

Now I realize how Concrete is working. But, in general, in TFHE one message is encrypted into an LWE ciphertext. Is that correct? Because in CKKS, there is a vector of plaintexts that are encrypted into one cihpertext. But in TFHE seems that there is one ciphertext per plaintext and all the computations are done for only one data.

So, what would be the maximum modulus for plaintext and ciphertext, and how larger the expansion factor would be in TFHE compared to CKKS?

Sorry if this is unrelated! I think it’s more a TFHE question than Concrete