Web-oriented Architectures: On the Impact of Web 2.0 on Service-oriented Architectures

Service-oriented architectures (SOAs) have been discussed intensively in science and industry since their first appearance in the mid-nineties. However even today there is no generally accepted method for modeling a SOA or for converting other concepts (e.g., monolithic architectures, CORBA landscapes) into a SOA. There are numerous standards available in the SOA context, but instead of easing the creation of a SOA, they typically make their realization more complicated. On the other hand, recent developments in the Web 2.0 context show how easy it can be to link or compose ("mesh") IT components dynamically, so that original SOA goals like flexibility or reduction of complexity can be achieved by relatively simple means. An interesting concept in this context is the Web-oriented architecture (WOA), which represents a specialization of SOAs obtained by using simple Web 2.0 technologies and standards. Since for a WOA no generally accepted modeling techniques are available either this paper reviews SOA models in light of their applicability to WOAs. A case study is used to discuss a possible realization and to preliminarily investigate the question of whether the intended simplicity can indeed be achieved