Tootfinder

Fair Data Exchange with Constant-Time Proofs
Majid Khabbazian
https://arxiv.org/abs/2506.14944 https://arxiv.org/pdf/2506.14944

Fair Data Exchange with Constant-Time Proofs
The Fair Data Exchange (FDE) protocol introduced at CCS 2024 offers atomic pay-per-file transfers with constant-size proofs, but its prover and verifier runtimes still scale linearly with the file length n. We collapse these costs to essentially constant by viewing the file as a rate-1 Reed-Solomon (RS) codeword, extending it to a lower-rate RS code with constant redundancy, encrypting this extended vector, and then proving correctness for only a small random subset of the resulting ciphertexts…