Feige–Fiat–Shamir (FFS) Identification Demo (1-bit)

Alice (Prover)

Alice proves knowledge of s without revealing it. Public values are N and v with v ≡ s² (mod N).

Round

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Secret s

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Public N

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Public v

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Commit r

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Commit x

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Challenge e

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Response y

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idle

→

Bob (Verifier)

Bob checks Alice using (N, v) and the transcript (x, e, y).

Round

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Public N

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Public v

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Recv x

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Sent e

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Recv y

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Check

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waiting