Stratified guarded first-order transition systems

Abstract First-order transition systems are a convenient formalism to specify parametric such as multi-agent workflows or distributed algorithms. In general, any nontrivial question about is undecidable. Here, we present three subclasses of first-order where every universal invariant can effectively be decided via fixpoint iteration. These defined in terms syntactical restrictions: negation, stratification and guardedness. While guardedness represents particular pattern how input predicates control existential quantifiers, limits the information flow between predicates. Guardedness implies that weakest precondition for again universal, while remaining sufficient criteria enforce either number occurring negated literals decreases iteration, required instances variables remains bounded. We argue each these cases termination iteration guaranteed. apply results identify classes systems, when formalized noninterference presence declassification decidable coalitions attackers bounded size.