How can i achieve 80-bit classic security in CKKS

FHE Questions
1

Hello.

I would like to set the parameters (multiplicative depth, ring dimension, etc.) for achieving 80-bit security in CKKS. For security levels of 128, 192, and 256 bits, I was able to use the SecurityLevel parameter in the OpenFHE library or reference standard.

However, when aiming for 80-bit security, I am unsure how to verify whether my parameter set meets the required security level. For instance, if I set the multiplicative depth to 30 and the ring dimension to 65536, is this appropriate for 80-bit security? I need assistance in choosing the right parameters.

Thank you for reading.

2

You can set the security level in OpenFHE to HEStd_NotSet and set the ring dimension yourself. Note that in this case you should find parameters yourself (outside OpenFHE). The standard tool to estimate the work factor for given parameters is the lattice estimator.