[Cryptography] Proposal of a fair contract signing protocol

[Salz, Rich]

> (a) The definition of unfairness I have in mind is: A valid contract C is unfair in
> its signing processing, if there existed a certain finite time interval in which
> one partner had already fully committed while the other had yet the
> freedom to commit or not.

This is handled by language that says the contract is not binding until all parties sign.