 Chapter IV Virtual Web Services: Extension Architecture to Alleviate Open Problems in Web Services Technology Julio Fernández Vilas University of Vigo, Spain Jose J. Pazos Arias University of Vigo, Spain Ana Fernández Vilas University of Vigo, Spain Copyright © 2009, IGI Global, distributing in print or electronic forms without written permission of IGI Global is prohibited. aBsTraCT Several open issues in Web services architecture are being solved by using different kinds of solutions. Standard high-availability techniques based on the use of Web servers, business-logic-based caching systems, dynamic binding of Web services by programming the access to a SOAP message content from the business logic layer, and other kinds of current open problems can now be handled using a common unique technique. What we propose is to apply virtualization techniques to Web services. inTroduCTion When referring to current Web service architecture, a very important aspect to take care of is the one related to the separation of roles and the meaning of each role inside the architecture. Although the distinction between client, provider, and directory is clear, a great part of the Web services technology is based on a Web service offered by a provider (Booth, Haas, McCabe, Newcomer, Champion, Ferris et al., 2004). That is, according to the roles of the current proposed architecture, the provider is intimately