An End-to-End Approach for QoS-Aware Service Composition

Abstract

Abstract-A simple and effective composition of software services into higher-level composite services is still a very challenging task. Especially in enterprise environments, Quality of Service (QoS) concerns play a major role when building software systems following the Service-Oriented Architecture (SOA) paradigm. In this paper we present a composition approach based on a domainspecific language (DSL) for specifying functional requirements of services and the expected QoS in form of constraint hierarchies by leveraging hard and soft constraints. A composition runtime will resolve the user's constraints to find an optimized composition semi-automatically. To this end we leverage data flow analysis to generate a structured composition model and use two different techniques for the optimization, a constraint programming and an integer programming approach.

Metaheuristic Optimization of Large-Scale QoS-aware Service Compositions

“…Basically, two different constraint types can be specified on the abstract composite service level [15]. Global constraints express QoS constraints for the overall abstract composite service.…”

Web Service Composition Processes: A Comparative Study

“…One of the solutions of such a problem [35] is to assign to each variable value from its domain that satisfies all constraints. The work in [39] propose a composition process modeled as a Constraint Optimization Problem (COP). The authors argue that the proposed process be flexible enough by applying soft constraints instead of hard constraints.…”

Semantic Web Services - Discovery, Selection and Composition Techniques

“…This is similar to workflow management, since the application logic there is also realized by composing autonomous legacy applications. This allows us to define increasingly complex applications as required by continuously evolving end-user requirements and business logic [14]. As different composed services work together, the output data of one may be the input for another.…”

“…With automated composition, the end user or application developer specifies a goal (a business goal expressed in a description language or mathematical notation) and an "intelligent" composition engine selects adequate services and offers the composition transparently to the user [14]. The main challenges are in identifying and selecting candidate services, composing them as required by the business logic, and analyzing the extent to which they match a request.…”