Protocol 2

Protocol assumption

The illustration below shows our second candidate protocol’s flow and messages.

As can be seen from the illustration below, Protocol 2 is very similar to Protocol 1. It’s in the protocol assumptions that the main differences lie:

• Bob has access to a source of randomness: This is the same as for Protocol 1.

• Alice has been issued a signature key, and Bob has access to a verification key that corresponds to Alice’s signature key: This is the digital signature scheme equivalent of the second assumption for Protocol 1.

• Alice and Bob agree on using a strong digital signature scheme.