Schnorr signature

In cryptography, a Schnorr signature is a digital signature produced by the Schnorr signature algorithm. Its security is based on the intractability of certain discrete logarithm problems. The Schnorr signature is considered the simplest digital signature scheme to be provably secure in a random oracle model. It is efficient and generates short signatures. It was covered by U.S. Patent 4,995,082 which expired in February 2008.

In the following,

To sign a message, ${\displaystyle M}$:

The signature is the pair, ${\displaystyle (s,e)}$.

Note that ${\displaystyle s,e\in \mathbb {Z} _{q}}$; if ${\displaystyle q<2^{160}}$, then the signature representation can fit into 40 bytes.

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