Enriching SDL Specifications with MSCs

Abstract Software systems evolve through addition of new behaviors and new components to the existing behavior and architecture. In this paper, we address the issue of enriching automatically SDL specifications with new behaviors specified with MSCs. The new behaviors should not inhibit (invalidate) existing and already validated behavior. In other words, the existing behavior should be preserved in the new SDL specification. We define formally the notion of behavior preservation in the context of SDL, taking into account its semantics, and we illustrate our SDL specification enrichment approach through an example.