ted on acid-free paper responsibly manufactured from sustainable forestry in which at least two trees are planted for each one used for paper production. To my parents To Martine To Elsa Contents Preface Foreword 1 Introduction 1.1 Validation of Communications Systems 1.2 SDL, Language to Master Complex Systems Development 1.2.1 Overview of SDL 1.2.2 Benefits provided by SDL 1.3 Simulation Life Cycle 1.4 Contents of the Book 1.5 Tools and Platforms Used 2 Quick Tutorial on SDL 2.1 Structure of an SDL Model 2.1.1 System, block and process 2.1.2 Scope of declarations 2.1.3 Process 2.1.4 Procedure 2.2 Communication 2.2.1 Signals 2.2.2 Channel 2.2.3 Signal route 2.3 Behavior 2.3.1 Structure of a transition 2.3.2 Start 2.3.3 States 2.3.4 Input 2.3.5 Save 2.3.6 Variables 2.3.7 Stop 2.3.8 Task 2.3.9 Create 2.3.10 Output 2.3.11 Decision 2.3.12 Timers 2.4 Data Types viii Contents 2.4.1 Predefined data 2.4.2 Array 2.4.3 Synonym and syntype 2.4.4 Newtype 2.5 Constructs for Better Modularity and Genericity 2.5.1 Package 2.5.2 Types, instances and gates 2.5.3 Specialization 3 The V.76 Protocol Case Study 3.1 Presentation 3.2 Specification of the V.76 Protocol 3.2.1 Abbreviations used 3.2.2 Exchange identification procedures (XID) 3.2.3 Establishment of a data link connection 3.2.4 Information transfer modes 3.2.5 Release of a DLC 3.3 Analysis MSCs for the V.76 Protocol The SDL Model of V.76 3.4.1 The simulation configuration of V.76 3.4.2 The package V76 3.4.3 The block dataLink 4 Interactive Simulation 4.1 Principles 4.2 Case Study with Tau SDL Suite 4.2.1 Prepare the Simulator 4.2.2 Validate against the main scenarios 4.2.3 Detect a bug in the SDL model 4.2.4 Detect nonsimulated parts 4.2.5 Validate against more scenarios 4.2.6 Write a script for automatic validation 4.2.7 Other Simulator features 4.3 Case Study with ObjectGeode 4.3.1 Prepare the Simulator 4.3.2 Validate against the main scenarios 4.3.3 Detect a bug in the SDL model 4.3.4 Detect nonsimulated parts 4.3.5 Validate against more scenarios 4.3.6 Write a script f