Proceedings

Abstract:

In this paper, we discuss the challenge and our experiences of re-engineering legacy police IT systems and transforming them into well orchestrated and co-ordinated Web Services. We use the Web Services Flow Graph (WSFG) to analyse the issues associated with Web Services composition, orchestration, as well as quality of service (QoS).

While QoS composition is to leverage, aggregate and bundle the individual Web services component's quality of service properties to derive the composite service component's QoS, we focus in this papper on QoS factoring, which is to work out a set of sub Web services components that could collectively fulfill the functionalities and meet requirements of the complex process within its QoS bound. We present an algorithm that is proposed for QoS factoring; we also disucss, as a case study, application of the algorithm in an ongoing national Web Services project involving service providers such as the Police National Computer (PNC), the New Scotland Yard, and several other forces in the UK.