Arthur-Merlin protocol

In computational complexity theory, an Arthur-Merlin protocol is an interactive proof system in which the verifier's coin tosses are constrained to be public (i.e. known to the prover too). This notion was introduced by Babai et al. They proved that all languages with constant-length interactive proofs with private coins also have interactive proofs with public coins. Later, Goldwasser and Sipser generalized this result to proofs of arbitrary length.
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