The two major platform contenders for Web Services are Microsofts .Net platform and the Java approach (with J2EE and EJB). To ensure that web service components from different vendors work together, various players in the industry have come together to form the Web Services-Interoperability (WS-I) organisation. Membership has grown from 10 companies in February to over 100 now. One important name still missing is Sun. WS-I is more likely to succeed, because, in the words of Ted Schadler of Forrester Research (quoted in the Financial Times), this profoundly simple commitment to interoperability will prevent the potential Balkanisation of emerging XML standards and ensure that firms that build web services will see them work together as intended with minimal hassle.
According to Adam Bosworth of BEA, there are three themes around which Web Services will be built: a coarse-grained application model (which enables multiple requests to be serviced via a single request), asynchrony (because applications may not always be running or may require time to return the result) and loose coupling (so that even if an implementation changes, it does not break the other applications using it). This move to a message-passing world will lay the foundation for the event-driven enterprise.
Says Adam Bosworth in an interview to XML and Web Services magazine (June 2001):
For example, you write a system that wants to go and order some medicine. Some other one has written an application that actually takes an order for medicine and processes itthey in turn talk to a system that is your bank that does bill paying and settlement. In that world, you have a couple of processes going on that aren’t synchronous in real time. When you order the prescription, you don’t want to actually have your bill debited until the prescription has been mailed out, and your bank takes a day or two to settle, depending on what you’re doingif it’s a brokerage house, it can take five days.
What you get is a model where applications need to be wired together so it’s easy for those applications to invoke each other in this kind of n-tier way. But they’re not invoking each other as a set of distributed objects, which was the original vision; they’re invoking each other as a set of applications that they can talk to.
The early adoption of Web Services will happen within the enterprise first. Once companies are comfortable using them, they will then be extended to connect applications across enterprises. The major benefits of Web Services, as outlined by Douglas Hayward in the Financial Times, are:
- By letting applications exchange information cheaply and automatically, web services should eventually slash the costs of tying applications together, a huge part of every corporate IT budget.
- A key benefit is the ability to aggregate data from multiple sources automatically, without end-users having to make any effort.
- Web services will dramatically decrease business interaction costs by allowing easier and cheaper communication between organisations.One benefit of application integration is that businesses can save money by using more externally provided software, accessing it as an online service, perhaps by renting it or paying by usage. The result could be a more accessible form of outsourcing, allowing companies to unload IT functionality which does not generate competitive advantage.
Tomorrow: Web Services and Business Processes