Brief announcement: RedRem: a parallel redundancy remover

Policies defined by a sequence of predicate-decision rules, with first-match semantics, are widely used; a notable example is their use in firewalls, where the rules are used to decide whether to accept or discard each packet. Owing to the critical importance of correctness of such policies, as well as the need for high performance, they have been the subject of considerable analysis. In earlier work, we have demonstrated that the problem of removing redundant rules from firewalls is theoretically equivalent to verifying that a firewall satisfies a property, and proposed that this theorem be used to build a high performance redundancy remover. In this paper, we realize this promise, and build a fast linear-space redundancy remover, one to three orders of magnitude faster than current approaches. Further, we show that our algorithm is easy to parallelize- there exists a natural way to partition a large instance of the problem into independent small ones.