Georg Jung

Cadena: an integrated development, analysis, and verification environment for component-based systems

The use of component models such as Enterprise Java Beans and the CORBA Component Model (CCM) in application development is expanding rapidly. Even in real-time safety/mission-critical domains, component-based development is beginning to take hold as a mechanism for incorporating non-functional aspects such as real-time, quality-of-service, and distribution. To form an effective basis for development of such systems, we believe that support for reasoning about correctness properties of component-based designs is essential. In this paper, we present Cadena - an integrated environment for building and modeling CCM systems. Cadena provides facilities for defining component types using CCM IDL, specifying dependency information and transition System semantics for these types, assembling systems from CCM components, visualizing various dependence relationships between components, specifying and verifying correctness properties of models of CCM systems derived from CCM IDL, component assembly information, and Cadena specifications, and producing CORBA stubs and skeletons implemented in Java. We are applying Cadena to avionics applications built using Boeings Bold Stroke framework.

Model-checking Middleware-based Event-driven Real-time Embedded Software ?

Component frameworks such as the CORBA Component Model (CCM) and middleware services such as the CORBA Event Service are increasingly being used to build safety / mission-critical distributed real-time embedded (DRE) systems. In this paper, we present a novel model-checking infrastructure for checking global temporal properties of DRE systems built on top of a Real-Time CORBA Event Service using CCM architectures. We describe how (a) building support for OO structures and communication layers directly in an extensible model-checker and (b) leveraging domain properties related to priorities, scheduling, and timing can dramatically reduce the costs of checking realistic systems.

CALM and Cadena: metamodeling for component-based product-line development

Large-scale software development efforts are increasingly based on product lines, a development process in which developers build the software for similar product families from reusable infrastructure and common application components. Existing software modeling approaches fail to support many product-line development activities. The Cadena platform, together with its core modeling concept, the Cadena Architecture Language with Metamodeling, addresses this deficiency by providing a highly adaptive type-centric modeling framework with robust, flexible, and extensible tool support.

Cadena: An Integrated Development Environment for Analysis, Synthesis, and Verification of Component-Based Systems

This tool paper gives an overview of Cadena – an integrated environment for building and modeling systems built using the CORBA Component Model (CCM). Cadena provides facilities for defining component types using CCM IDL, specifying dependency information and transition system semantics for these types, assembling systems from CCM components, visualizing various dependence relationships between components, specifying and verifying correctness properties of models of CCM systems derived from CCM IDL, component assembly information, and Cadena specifications, and producing CORBA stubs and skeletons implemented in Java. Cadena has been applied to build applications in Boeing’s Bold Stroke framework for avionics mission-control systems. Cadena is implemented in IBM’s Eclipse open-source IDE and is freely available.

SCA and jABC: Bringing a Service-Oriented Paradigm to Web-Service Construction

Extensibility, flexibility, easy maintainability, and long-term robustness are core requirements for modern, highly distributed infor- mation and computation systems. Such systems in turn show a steady increase in complexity. In pursuit of these goals, software engineering has seen a rapid evolution of architectural paradigms aiming towards increasingly modular, hierarchical, and compositional approaches. Object-orientation, component orientation, middleware components, product-lines, and - recently - service orientation. We compare two approaches towards a service-oriented paradigm, the Service Component Architecture (SCA) and the jABC.

A type-centric framework for specifying heterogeneous, large-scale, component-oriented, architectures

Maintaining integrity, consistency, and enforcing conformance in architectures of large-scale systems requires specification and enforcement of many different forms of structural constraints. While type systems have proved effective for enforcing structural constraints in programs and data structures, most architectural modeling frameworks include only weak notions of typing or rely on first-order logic constraint languages that have steep learning curves and that become unwieldy when scaling to large systems. We present the CADENA Architecture Language with Meta-modeling (CALM) - that uses multi-level type systems to specify and enforce a variety of architectural constraints relevant to development of large-scale component-based systems. CADENA is a robust and extensible tool that has been used to specify a number of industrial-strength component models and applied in multiple industrial research projects on model-driven development and software product lines.

A Correlation Framework for the CORBA Component Model

Large distributed systems, including real-time embedded systems, are increasingly being built using sophisticated middleware frameworks. Communication in such systems is often realized using in terms of asynchronous events whose propagation is implemented by an underlying publish/subscribe service that hooks components into a generic event communication channel. Event correlation – a mechanism for monitoring and filtering events – has been introduced in some of these systems as an effective technique for reducing network traffic and computation time. Unfortunately, even though event correlation is used heavily in frameworks such as ACE/TAO’s real-time event-channel and in mission critical contexts such as Boeing’s Bold Stroke avionics middleware, the industry standard CORBA Component Model (CCM) does not include a specification of event correlation. While previous proposals for event correlation usually offer sophisticated facilities to detect combinations in the stream of incoming events, they have not been constructed to fit within the CCM type system, and they offer relatively little support for transforming and rearranging filtered events into meaningful output events. In this paper, we present the design rationale, syntax, and semantics for a new and highly flexible model for event correlation that is designed for integration into the CCM type system. Our model has been integrated and tested in the Cadena development and analysis framework, which has been designed to support development of mission-control applications in the Boeing Bold Stroke framework.

Slicing and partial evaluation of CORBA component model designs for avionics system

The use of component models such as Enterprise Java Beans and the CORBA Component Model (CCM) in application development is expanding rapidly. Even in real-time safety-critical and mission-critical domains, component-based development is beginning to take hold as a mechanism for in-corporating non-functional aspects such as real-time, quality-of-service, and distribution.

A correlation framework for the CORBA component model

Large distributed systems, including real-time embedded systems, are increasingly being built using sophisticated middleware frameworks. Communication in such systems is often realized using in terms of asynchronous events whose propagation is implemented by an underlying publish/subscribe service that hooks components into a generic event communication channel. Event correlation—a mechanism for monitoring and filtering events—has been introduced in some of these systems as an effective technique for reducing network traffic and computation time. Unfortunately, even though event correlation is used heavily in frameworks such as ACE/TAO’s real-time event-channel and in mission critical contexts such as Boeing’s Bold Stroke avionics middleware, the industry standard CORBA Component Model (CCM) does not include a specification of event correlation. While previous proposals for event correlation usually offer sophisticated facilities to detect combinations in the stream of incoming events, they have not been constructed to fit within the CCM type system, and they offer relatively little support for transforming and rearranging filtered events into meaningful output events. In this paper, we present the design rationale, syntax, and semantics for a new and highly flexible model for event correlation that is designed for integration into the CCM type system. Our model has been integrated and tested in the Cadena development and analysis framework, which has been designed to support development of mission-control applications in the Boeing Bold Stroke framework.