Middleware support for embedded software with multiple QoS properties for ubiquitous computing environments

Ubiquitous application software usually has multiple QoS requirements, such as situation-awareness, real-time, and security, which make the application software development complicated. In this paper, an approach to supporting multiple QoS properties in application software using middleware is presented. Our reconfigurable context-sensitive middleware (RCSM), which provides situation-awareness support to the application software, is expanded to support more QoS by using aspect-oriented software development techniques. In the expanded RCSM, each QoS is processed through a set of aspect components. The application developers specify the QoS requirements in a specification file, which is in turn compiled to configure the corresponding aspect components. Being associated with certain application objects, the QoS aspect components enforce the QoS requirements according to the specification during run-time. In this paper, security, in addition to situation-awareness, is used as an example to illustrate our approach.