OBSTACLES TO ADOPTION

As discussed in Chapter 2, “Standards, Concepts, and Terminology,” Web services standards are currently at varying degrees of maturity. On one end of the maturity spectrum the enabling standards are very solid, while on the other end of the spectrum the emerging standards are still very much in flux. As we look at the Web services adoption model, there are significant gaps in the emerging standards that need to be resolved to allow Web services to progress. These gaps represent potential obstacles to the Web services adoption model and, if left unresolved, will likely slow the adoption of Web services beyond basic integration and rudimentary collaboration capabilities. Figure 3.7 illustrates the four adoption phases and associated obstacles to adoption.

Figure 3.7: Obstacles to Web services adoption.

As Figure 3.7 illustrates, the obstacles to Web services adoption are primarily centered on the collaboration phase. As the collaboration phase gains momentum, the demands for greater collaboration will progressively require the following:

1. Security —Web services will undoubtedly introduce additional security risks for organizations that chose to expose services outside of the corporate firewall. Early collaboration initiatives can use Virtual Private Networks (VPNs) to create a closed network of trusted partners, but security standards for using Web services over the public Internet are only now being defined. Refer to Chapter 2, “Standards, Concepts, and Terminology,” for more information on Web services security standards.

2. Services Management —As the number of Web services in use increases, it becomes increasingly important for organizations to understand what, when, where, and by whom services are being used. Much as with e-Commerce initiatives, it will become important to monitor the Quality of Service (QoS) that Web services are providing for partners, suppliers, and customers.

3. Asynchronous Transactions— As collaborative Web service transactions become more complex, they will gain longevity. Long-running transactions that persist indefinitely will eventually become common. In this environment, once a complex set of transactions has been started, it will be necessary to know the success or failure of a number of related transactions to determine an overall success or failure status. For example, if you are booking travel to Seattle, a booking system might include the transactions of booking the flight, the hotel, and the rental car. In this scenario you would only want to confirm the hotel and car rental if the flight is booked successfully. In recent months IBM, Microsoft, and BEA published the Web services Transaction (WS-Transaction) proposed standard to tackle this issue. WSTransaction is still very much an emerging standard, and as such it is not yet clear if it will gain widespread acceptance and adoption for Web services transaction management.

4. Process Orchestration and Workflow —As the portfolio of available Web services, both within and across organizations, continues to grow, it will become increasingly important to orchestrate Web services as part of end-to-end business processes or workflows. For example, you might want to automate the booking process discussed above, using a process-driven booking and confirmation system. A booking agent or consumer might enter all the travel requirements via a Web site, and the orchestrated booking process manages the individual Web services for each step of the overall transaction. Obviously, the ability to determine success or failure of each individual step of the process is an important prerequisite for the implementation of process orchestration.

Again, IBM, Microsoft, and BEA have published proposed standards to tackle the Web services process orchestration requirements. The Web Services Coordination (WS-Coordination) and Business Process Execution Language for Web Services (BPEL4WS) are leveraged together first to coordinate a group of Web services, and secondly to weave a coordinated group of services into a higher-level business process. As with WS-Transaction, WS-Coordination and BPEL4WS are emerging standards, and have yet to gain widespread acceptance and adoption.

These obstacles are only potential roadblocks, and in many instances major industry players like IBM and Microsoft are already actively engaged in proposing and developing potential solutions as with WS-Security, WSTransaction, etc. The real test for these proposals is gaining the broad acceptance required to prevent the fragmentation of Web services standards, or if other organizations undermine them by pushing their own proposed standards.