User-centric Service Composition - Towards Personalised Service Composition and Delivery

With computing devices and the Internet becoming ubiquitous, users can make use of network-based software applications in different places and situations. Mobile devices with Internet connectivity are a good example of this trend. Network-based software applications are being exposed to users as web services, which makes them accessible on demand, when and where the users require them in their daily life. Often users have to make use of several services to fulfil their requirements. The required services can be combined into a service composition, to deliver a value-added service that fulfils all the different requirements of a given user at a given moment. Creating such service compositions beforehand is difficult, or even impossible, as service developers would need to define all the possible service compositions that end-users may require. However, and given that services can be exposed through the Internet, service compositions can possibly be created on demand, driven by the users, whenever users require a given functionality that cannot be delivered by a single existing service. In this thesis we address the problem of personalised service delivery through on demand composition of existing services. To achieve such personalised service delivery, we claim that usercentric service composition supporting approaches are required. User-centric service composition aims at the creation of a new service composition to fulfil the requirements of a specific enduser. Furthermore, we also consider that service composition supporting process needs to be personalised to the user creating the service composition, which is not necessarily the service end-user. Proper attention should be given to the fact that users are heterogeneous, i.e., they have different knowledge, technical skills and may use services in different situations. Furthermore, this process will mainly take place at runtime, which imposes real-time behaviour constraints to the service composition supporting system. We assume that in many application domains users have lim-