Towards byzantine fault tolerant publish/subscribe: A state machine approach

More than a decade of research has gone into techniques aimed at tolerating arbitrary failures in client/server inter-action, using consensus based replication. These works made Byzantine fault tolerance possible [5], competitive [18], ro-bust [7], and feasible to apply [6]. In this paper we estab-lish a connection between the pub/sub interaction model and consensus based replication protocols, that makes the above results applicable to the design of large scale event-based middleware. We propose a Byzantine fault tolerant pub/sub system, on a tree-based overlay, tolerating a con-figurable number of failures in any part of the system, with minimal divergence from traditional pub/sub specifications and forwarding schemes