Web Page Design and Hosting

5.6 Outlook 107 The Web Service Choreography Interface (W3C 2002a) and the competing Web Services Conversation Language (W3C 2002b) offer a way to specify messages participating in a service and their structures as well as the sequence in which these messages should be exchanged. BPEL4WS (Business Process Execution Language for Web Services), or BPEL for short (IBM 2005a), builds on the former, allowing describing complex business processes (workflows). BPEL can be used to describe control flows and dependencies between participating processes. In addition to BPEL4WS and WSCI/WSCL (which is suitable not only for the purpose discussed here), a number of other manufacturer-specific protocols are available to describe business processes in XML. (Bernauer et al. 2003) includes a more detailed comparison of the protocols mentioned here and other protocols, which are not based on the Web services protocol stack. Another important issue for business over the Internet concerns security aspects, briefly outlined in Figure 5-3 with WS-Security as an example. Authenticity, confidentiality, integrity, and non-repudiation play a central role in this issue. Chapter 13 will discuss this issue in connection with Web services. Based on the business-to-business (B2B) approach, Web applications appear to evolve into huge systems distributed over many computers. This approach integrates not only a company s internal applications, but also third-party applications (services). Some companies already have extensive access to third-party applications under the catchword Supply Chain Management (SCM). Web services are expected to standardize this approach on the Web. Some research work has already been undertaken to select services on the fly as needed, depending on the situation. The Service Provisioning Markup Language (SPML), which can be used for the billing of services used, represents a first step towards this direction. 5.6 Outlook The so-called post-PC era is no longer dominated by one single class of devices (the PC), but characterized by a large number of different devices. During the next few years, mobile devices will be of major importance, as mentioned in section 5.3.2. Therefore, in order to be sustainable, Web applications have to be prepared for this trend today, namely by considering two important concepts, i.e., context awareness and device independence, which will be discussed in sections 5.6.1 and 5.6.2, respectively. Since the first of these two concepts is still in the research stage, section 5.6.1 will just explain aspects that should be observed in the design of context-aware Web applications. Section 5.6.3 will exclusively focus on giving an outlook on new or missing concepts in engineering that could generally promote the sustainability of Web applications in the future. 5.6.1 Context-aware Applications A context-aware application is an application that takes user-specific knowledge a user s context to optimally customize both its interaction and its function. In addition, context awareness leads to new types of applications, e.g., Location-Based Services (LBSs), to mention one example. Depending on the location, we could, for instance, display tailored information

Note: If you are looking for good and high quality web space to host and run your java application check Lunarwebhost java web hosting services