Beschreibung
but when we state that A 'equals' B, as well having to know what we mean by A and B we also have know what we mean by 'equals'. This section explores the role of observers; how different types of observ er see different things as being equal, and how we can produce algo rithms to decide on such equalities. It also explores how we go about writing specifications to which we may compare our SCCS designs. - The final section is the one which the students like best. Once enough of SCCS is grasped to decide upon the component parts of a design, the 'turning the handle' steps of composition and check ing that the design meets its specification are both error-prone and tedious. This section introduces the concurrency work bench, which shoulders most of the burden. How you use the book is up to you; I'm not even going to suggest path ways. Individual readers know what knowledge they seek, and course leaders know which concepts they are trying to impart and in what order.
Autorenportrait
Inhaltsangabe1 Scene Set.- 1.1 Making Models.- 1.2 Lies, Damn Lies and Models.- 1.3 Abstraction, Atomicity and Algebras.- 1.3.1 Algebras, Specifications and Other Related Things.- 1.4 Labelled Transition Systems.- 1.4.1 An Algebra of Transition Systems.- 1.5 One at Once, All Together and In Time.- 1.5.1 A Process Algebra for Sequential Systems.- 1.5.2 A Process Algebra for Concurrent Systems.- 1.6 Real-Time Systems.- 2 Concurrency and Communication.- 2.1 Concurrency - Defining the Problems.- 2.2 Programming Domain Solutions.- 2.2.1 Mutual Exclusion.- 2.2.2 Critical Sections.- 2.2.3 Synchronisation.- 2.2.4 Semaphores.- 2.2.5 Monitors.- 2.3 Review and Rethink.- 3 Message Passing.- 3.1 Choosing the Best.- 3.1.1 The Contenders.- 3.1.2 The Choosing.- 3.2 Blocking Send.- 3.3 CCS (Calculus of Communicating Systems).- 3.4 Rendezvous.- 3.5 Conclusion.- 4 Synchronous Calculus of Communicating Systems.- 4.1 An Overview of SCCS.- 4.2 Plain SCCS.- 4.2.1 Naming of Parts.- 4.2.2 Basic Operators and Propositions.- 4.3 Recursion.- 4.3.1 Recursion in SCCS Terms.- 4.3.2 Derived Agents.- 4.4 Actions, Particles, Composites and All Sorts.- 4.5 Synchronisation.- 4.5.1 Interaction.- 4.6 Constructional Design.- 4.6.1 Scoping and Synchronisation.- 4.6.2 Choice of Choices.- 4.6.3 Example - Software Interrupts.- 4.6.4 Distributing Pruning over Product.- 4.7 Message Passing.- 4.7.1 Parameter Passing.- 4.7.2 Message Passing.- 4.7.3 Predicated Choice.- 4.8 Agents Lurking.- 4.8.1 Delay ?.- 4.8.2 One Agent Waits.- 4.8.3 Both Agents Wait.- 4.8.4 Examples.- 4.8.5 Message Passing and Waiting.- 4.9 Specifications and Proof.- 4.9.1 Mutual Exclusion.- 4.9.2 Livelock - Software Scheduler.- 4.9.3 Deadlock - Software Scheduler.- 4.9.4 Comments.- 5 Equivalence.- 5.0 The Need For Equivalence.- 5.1 Traces.- 5.2 From Traces to Bisimulations.- 5.3 Bisimulation.- 5.3.1 Strong Bisimulation.- 5.3.2 From Strong Bisimulation to an Equivalence.- 5.3.3 Observational Equivalence.- 5.3.4 Observational Congruence.- 6 Automating SCCS.- 6.0 Concurrency Work Bench: an Introduction.- 6.1 CWB and Agent Behaviours.- 6.2 Agents, Bisimulation and CWB.- 6.3 Comments.- 7 Proving Things Correct.- 7.1 Modal Logics.- 7.1.1 Hennessy-Milner Logic.- 7.1.2 Propositional Modal Mu-Calculus - Modal Logic plus Fixed Points.- 7.2 Modal Logic, CWB and Satisfaction.- 8 End End Note.- Appendix 1 Some of the More Useful SCCS Propositions.- Appendix 2 Notation Used Throughout the Book.- References.
