Modeling QoS Parameters in Component-Based Systems

摘要

Current trends in the software development are focused on creating systems by integrating previously developed software components. This approach aids in the reusability of the code and helps to reduce the cost of software development. In addition to the functionality a component offers, it may contain the necessary code for measuring how well the functionality will be achieved during the execution. This gives rise to the notion of quality of service (QoS) offered by a component -- latency, throughput, capacity, precision, etc., are a few examples of QoS parameters. Many applications, such as multi-media, emphasize and require a certain level of the QoS offered by components. Thus, it is critical to model the QoS, at an appropriate level of an abstraction, during the modeling of component-based systems. Such a modeling will not only assist the component developers but also emphasize the need for integrating the QoS during the development and implementation phases of the software design. In this thesis, an approach based on a unified framework (UniFrame) is proposed to model the QoS parameters in component-based systems. The approach involves QoS concepts relevant for specifying QoS, a UML profile for representing the concepts, integrating the QoS specification with the functional specification and mapping the specification manually onto the code of the component.