As with other digital signature schemes, Ed25519 consists of three protocols: key generation, signing and verification. They are similar, but distinct, from the generic Schnorr scheme.
Key Generation
Ed25519 does not match secret keys to scalars. Instead, a secret scalar is generated from a seed, a 32-byte string, which should be filled at random from a cryptographically secure RNG.
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Signing
Signing in Ed25519 is deterministic: it doesn't require an RNG during signing. A faulty RNG during signing can leak the secret key, so this is an understandable design choice.
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Verification
Verification uses the equation following from Schnorr and the modified signing procedure:
[s]B == R + [H(R ‖ A ‖ M)]A.Loading interactive parts
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