A-DynamiCoS: A Flexible Framework for User-centric Service Composition

Service composition has been acknowledged as a promising approach to create new (composite) services that are capable of supporting multiple needs of service users. Service composition has been used quite extensively to support complex but relatively stable enterprise processes. More recently, service composition is also being applied to support the personalization of services delivered to human end-users. In these situations, the aim is to create service compositions on demand, at runtime, that match the specific requirements of each individual end-user, characterizing user-centric dynamic service composition processes. The most common approach to dynamic service composition aims at creating service compositions that once obtained must be deployed and executed by some sort of orchestration engine. In this approach, the service composition life-cycle is fixed, with serious limitations to its applicability in more realistic situations. This paper presents the A-DynamiC oS framework, which applies a novel approach to user-centric service composition by providing flexible support to the different activities of the service composition life-cycle. In this approach, components that perform service discovery, composition and execution activities are orchestrated, breaking the traditional rigid life-cycle (discover, then compose, then deploy and finally execute). We claim that dynamic orchestration of service composition activities enables true user-centric service delivery. This paper motivates and justifies the development of A-DynamiC oS, and presents use cases that demonstrate our claims.