Communicating Systems

Transcription

1 Communicating Systems with UML 2 Modeling and Analysis ofnetwork Protocols David Garduno Barrera Michel Diaz LEEJTEE WILEY

2 Table of Contents Preface xi Chapter 1. Why Use UML to Model Network Protocols? Modeling network protocols The complexity of communication protocols Traditional modeling Basic models and formal description techniques Automata and state machine models Petri Net models Formal and semi-formal languages Towards a new modeling language Traditional validation Need for a unified language for description, validation and simulation UML as a common language Overview The beginning Brief review Class diagram Package diagram Object diagram Component diagram Composite structure diagram Deployment diagram Sequence diagram Profile diagram 22

3 vi Communicating Systems with UML Activity diagram Communication diagram Interaction overview diagram Timing diagram Use case diagram State machine diagram UML for network protocols Some general UML tools 1.3. Chapter summary Bibliography 28 Chapter 2. Simple Transmission Introduction Echo Requirement specification Analysis Sequence diagram Concerned classes Signals list definition Architecture design Detailed design: class behavior Client class Server class Echo: validation and simulation Simulating the model Model validation Unidirectional: simple data sending Requirement specification Analysis Sequence diagram Signals list definition Architecture design Detailed design First variation: protocol notation (transition oriented) Second variation: behavior notation (state oriented) Validation and simulation Simulating the model Model validation Full duplex: simple data sending 52

4 Table of Contents vii Specification Analysis Sequence diagram Concerned classes Architecture design Validation and simulation Simulating the model Model validation Different ways of doing the same thing A single machine Interruption Composite states with concurrent regions Parallel threads Chapter summary Bibliography Chapter 3. Simple Chat Application Introduction Requirements 3.3. Analysis Sequence diagrams Splitting the system up Open session Timeout Refuse Accept Close Send data Concerned classes Signal list definition Architecture design Detailed design Open session Timeout Refusing the session Accepting session Closing session Sending data Case 1: Successful delivery

5 B-sends viii Communicating Systems with UML Case 2: the receiving user closes the session Case 3: The whole session is closed Simple chat simulation Intuitive test Initial tests Refuse session Accept session Close session Send data Coverage statistics Extended tests (fault tolerance) Proposed scenarios Ill Send when session is closed Ill A-Sends while B-Closes Close (with session closed) Open (when session is already opened) A-Opens - B-Opens A-Closes-B-Closes A-sends Chapter summary Bibliography 131 Chapter 4. Non-reliable Transmission Mediums Introduction Requirements Analysis Sequence diagrams Configure Send Concerned classes Accessory classes Class diagram Signal list definition Architecture design Detailing the sequence diagram Detailed design Random class ini operation rand operation 152

6 Table of Contents ix randab operation Losing class setlossesrate operation Initialize operation Delaying class setmaxdelay operation Initialize operation Non-reliable medium class Initialize operation Validation Configure Send Neither losses nor delay Losing everything No losses and high delay Losses and delay Extending the model Adding a payload Consecutive data packets Chapter summary Bibliography 179 Chapter 5. Simple Transport Protocol Introduction Requirements The Alternating Bit Protocol Basic communication features with Petri Nets The algorithm Analysis First step: The Alternating Bit Protocol Second step: Linking the application Third step: Linking the medium Concerned classes Signal list definition Architecture design Simple transport protocol Simulation model Detailed design ADU data type 204

7 x Communicating Systems with UML PDU data type ADUJvlanager PDU_Manager ABP_Sender ABPJReceiver Simulations Initialization and configuration No losses Open session request without answer Open session request with answer Send data Losses Further considerations Acknowledgements at different levels Delayed acknowledgements Chapter summary Bibliography 239 Appendix. Detailed Diagrams of the Simple Transport Protocol 241 A.l. State machines for the Application Data Unit Manager (Simple Transport Protocol) 242 A.2. Detailed simulations of the Simple Transport Protocol 245 A.2.1. Initializing and configuring the medium 245 A.2.2. No losses 246 A Open session request without answer 246 A Open session request with answer 248 A Send data 249 A.2.3. Losses 250 A.2.4. Losses and delay 253 Index 259