Model-driven Configuration and Deployment of Component Middleware Publisher/Subscriber Services

Though component-based software development is widely accepted in the enterprise business and desktop application domains, developers of distributed real-time and embedded (DRE) systems have encountered limitations with conventional component middleware platforms, such as the CORBA Component Model (CCM) and the Java 2 Enterprise Edition (J2EE). These limitations often preclude developers of DRE systems from fully exploiting the benefits of component software. In particular, while quality of service (QoS)-enabled publisher/subscriber services are available in component middleware platforms, these platforms lack a simple and intuitive way to integrate publisher/subscriber service configurations and deployments. The result is that developers of DRE systems must rely on ad hoc, tedious, and error-prone methods of integrating and deploying publisher/subscriber service configurations in component middleware. This paper makes four contributions to the integration of QoS-enabled publisher/subscriber services in component middleware for use in DRE systems. First, we describe key challenges associated with configuring and deploying publisher/subscriber services in QoS-enabled component middleware. Second, we present a methodology for resolving these challenges based on the Model-Driven Middleware (MDM) paradigm, which is an emerging generative programming technology that integrates model-based software development paradigms with component middleware to resolve software development and validation challenges of large-scale DRE systems. Third, we describe an MDM tool we have developed to automate and simplify the configuration and deployment of publisher/subscriber services in QoS-enabled component middleware applications. Fourth, we evaluate empirically how MDM reduces the amount of handwritten code in developing component applications that utilize publisher/subscriber services. Our results applying MDM to a 50 component avionics mission computing scenario show that MDM dramatically reduces handwritten code via automated configuration of a reusable component framework, while simultaneously eliminating low level accidental complexities incurred in handcrafting 100+ XML-based descriptor files used for configuring the ∗This work was sponsored in part by grants from NSF ITR CCR-0312859, Siemens, and DARPA/AFRL contract #F33615-03-C-4112 real-time publisher/subscriber services.