US Patent 9418130 Data replication protocol with efficient update of replica machines

Steady state data distribution is provided between a client application, a leader machine, and a plurality of replica machines. The distribution comprises the leader machine receiving an operation request from the client application, the leader machine sending the prepare message to each of the plurality of replica machines, the replica machines recording in their logs information on the operation, the replica machines sending acknowledgement messages to the leader machine, and the leader machine sending commit command messages to the replica machines. A new quorum of the replica machines is created by using log information. Replica machines that become part of the new quorum are updated in an efficient manner.