* Print timing for a regular Poseidon recursive proof Rather than the Keccak-256 proof. I kept it but hid the timing since it's less important to us. Alternatively we could test Keccak-256 only in the size-optimized test, since that's basically testing a bridge proof. Let me know if you have a preference. * Remove Keccak proof per PR discussion
plonky2
plonky2 is an implementation of recursive arguments based on Plonk and FRI. It uses FRI to check systems of polynomial constraints, similar to the DEEP-ALI method described in the DEEP-FRI paper. It is the successor of plonky, which was based on Plonk and Halo.
plonky2 is largely focused on recursion performance. We use custom gates to mitigate the bottlenecks of FRI verification, such as hashing and interpolation. We also encode witness data in a ~64 bit field, so field operations take just a few cycles. To achieve 128-bit security, we repeat certain checks, and run certain parts of the argument in an extension field.
Running
To see recursion performance, one can run this test, which generates a chain of three recursion proofs:
RUST_LOG=debug RUSTFLAGS=-Ctarget-cpu=native cargo test --release test_recursive_recursive_verifier -- --ignored
Disclaimer
This code has not been thoroughly reviewed or tested, and should not be used in any production systems.