DRIFT: Efficient message ordering in ad hoc networks using virtual flooding

We present DRIFT --- a total order multicast algorithm for ad hoc networks with mobile or static nodes. Due to the ad hoc nature of the network, DRIFT uses flooding for message propagation. The key idea of DRIFT is virtual flooding --- a way of using unrelated message streams to propagate message causality information in order to accelerate message delivery. We describe DRIFT in detail. We evaluate its performance in a simulator and in a wireless sensor network. In both cases our results demonstrate that the performance of DRIFT exceeds that of the simple total order multicast algorithm designed for wired networks, on which it is based. In simulation at scale, for certain experiment settings, DRIFT achieved speedup of several orders of magnitude.