What is Service Differentiation

This chapter aims at the design and implementation of a service-oriented architecture (SOA), named WSARCH – Web Services Architecture - which allows accessing Web Services using a combination of functional and non-functional aspects of Quality of Service (QoS). These QoS aspects, aiming at evaluating the performance of Web Services in order to achieve QoS in a service-oriented architecture, are identified and discussed. These QoS attributes were mapped to the components participating in a service-oriented architecture with QoS support. The proposed architecture provides the monitoring of service providers and the data obtained are used to locate the most appropriated service. The WSARCH can be used as an analytical platform for purposes of testing Web Services and understanding their behavior as well as an execution platform for building live systems. A prototype for the WSARCH was developed, and it can allow performance evaluation studies being conducted considering different components of the architecture, algorithms, protocols and standards. The proposal WSARCH is inserted into a context where it is important to define the way a SOA focusing on performance shall be designed, since the correct characterization of what to evaluate and how to evaluate.