Doctoral Topic Proposal: Towards Principled Fine-Grain Composition of Middleware

Middleware for Distributed Real-time Embedded (DRE) systems has grown more and more complex in recent years due to the varying functional and temporal requirements of complex real-time applications. To enable DRE middleware to be configured and customized to meet the demands of different applications, a body of ongoing research has focused on applying model-driven development techniques to developing QoS-enabled middleware. While current approaches for modeling middleware focus on easing the task of assembling, deploying and configuring middleware and middleware-based applications, a more formal basis for correct middleware composition and configuration in the context of individual applications is needed. While the modeling community has used high level formal models to uncover certain flaws in system design, a more formal, fundamental and lower-level set of models is needed to be able to uncover more subtle safety and timing errors introduced by interference between application computations, particularly in the face of alternative concurrency strategies in the middleware layer. In this research, we will examine how formal models of lower-level middleware building blocks provide an appropriate level of abstraction both for modeling and synthesis of a variety of kinds of middleware from these building blocks. When combined with model checking techniques, these formal models can help developers in composing correct combinations of middleware mechanisms, and configuring those mechanisms for a particular application. This research will thus have an impact on two different research communities. First, by modeling well-known low-level middleware abstractions such as reactors, acceptors, connectors, and service handlers, this work will establish concrete, canonical reference models for use by the formal systems modeling community. Second, by using those low-level models to evaluate particular concurrency and communication strategies in current use, this work will increase the rigor of current analysis and checking approaches used by higher-level model-based middleware development techniques.