Web Services Are Still Evolving

We have explored Web services in detail, including various programming techniques and how to build the distributed applications. But you have to be aware of one significant point: Web services are still in an evolving stage. With today's Web service tools and frameworks, you can build distributed applications that communicate by sending SOAP messages.

But you cannot employ Web services simply in mission-critical business, financial, or realistic applications. Why? The baseline specifications, such as WSDL, UDDI, and SOAP, are in a budding process. Moreover, there are some limitations in the present Web services, such as security, reliability, transaction processing, messaging and routing, quality of service, interoperability, and operational management. These limitations must be resolved to make use of Web services in real-time applications. To address these problems, Microsoft, IBM, and others have been working on the Global XML Web Services Architecture platform. The Global XML Architecture (GXA) is a series of specifications such as WS-Security, WS-Routing, WS-Inspection, WS-Addressing, WS-Policy, WS-Referral, WS-Coordination, WS-ReliableMessaging, and WS-Transaction, that extend SOAP and facilitate development of better real-time Web services.