On a time enriched OCL liveness template

It is increasingly recognised that non-functional requirements should be considered at the earliest stages of system development. Unified modelling language (UML), as a standard, should therefore include notation to capture such requirements. Among these, timing has received considerable attention by the modelling community with several timed extensions of UML diagrams, a UML profile and tools. However, timing constraints are, generally, not captured in a satisfactory way during design. We propose to use UML's object constraint language (OCL) for this purpose, and provide a simple time enriched liveness template for OCL. We describe the benefits of using this template. Having verification in mind, several logic-based formalisms could be chosen to underly OCL. We consider a novel real-time logic of knowledge, and argue why logics of knowledge are useful and promising in this context. We illustrate our approach with a distributed real-time system. Future work and further benefits of the knowledge-based framework are discussed at the end of the paper. Work reported here was supported by the EPSRC grants GR/R16891 and GR/N13999.