Especificação formal de sistemas de telefonia em estelle: um estudo de caso.

Abstract

The Formal Description Technique ( F D T ) Extended State Transition Language (Estelle), standardized by International Organization for Standardization (ISO), was developed for the formal specification of distributed systems and communication protocols. The main goal of this work is to investigate the possibility of using Estelle for the formal specification of telephony systems. First, the most relevant concepts of Estelle are discussed and illustrated through a simplified telephony system. Then, the call setup procedures of the Tropico RA telephony system, developed by CPqD/TELEBRAS, are formally specified and this specification is validated using the set of integrated tools Estelle Work Station (EWS).