global protocol SimpleVoting(role Voter, role Server){
    Authenticate(String) from Voter to Server;
    choice at Server {
        Ok(String) from Server to Voter;
        choice at Voter {
            Yes(String) from Voter to Server;
        } or {
            No(String) from Voter to Server;
        }
        Result(Int) from Server to Voter;
    } or {
        Reject(String) from Server to Voter;
    }
}