Authentication in a reconfigurable byzantine fault tolerant system 2004 1 citations ? 0 self

Abstract:  Byzantine (i.e. arbitrary) faults occur as a result of software errors and malicious attacks; they are increasingly a problem as people come to depend more and more on online services. Systems that provide critical services must behave correctly in the face of Byzantine faults. Correct service in the presence of failures is achieved through replication: the service runs at a number of replica servers and as more than a third of the replicas are non-faulty, the group as a whole continues to behave correctly. We would like the service to be able to authenticate data. Authenticated data is data that more than a third of the service is willing to sign. If a long-lived replicated service can tolerate f failures, then we do not want the adversary to have the lifetime of the system to compromise more than f replicas. One way to limit the amount of time an adversary has to compromise more than f replicas is to reconfigure the system, moving the responsibility for the service from one group of servers to a new group of servers. Reconfiguration allows faulty servers to be removed from service and replaced with newly introduced correct servers. Reconfiguration