Foreword

Web services are probably the most often written-about technology paradigm in today s trade press. Not a single day goes by, when I read at least one article daily touting the values of Web services. If you are new to Web services, you may be wondering why there is so much coverage about Web services. There are several reasons for the wide following of Web services, and this book provides a very good perspective of the business and technical benefits of Web services. Web services are positioned as the ideal solution to efficiently integrate the IT infrastructure. Let me explain the challenges of today s IT infrastructure in order to fully understand Web services.

Businesses are increasingly relying on IT to achieve their business goals. There is no question that businesses can increase their efficiencies by automating the business processes. There are scores of business applications available in the marketplace to automate your business processes. You can pick and choose the business application based on any number of criteria. For example, an enterprise might have purchased an accounting package 15 years ago that runs on IBM s AS/400, a home-grown inventory system that was built 5 years ago using Oracle Database running on HP UNIX, and a CRM system bought from a leading vendor last year. These applications typically work in a Silo ; that is, the business process associated with the application starts and ends within that application and doesn t interact with other applications. Although each of the applications delivers the business service that it has been designed for, it does not truly address the need for today s business challenges.

Today s business processes are all about collaboration. Business processes have to leap over departmental, divisional , and enterprise boundaries. In other words, a business process may have to collaborate with specific services offered by the Silo applications. For example, in a supply chain management process, a buyer in the United States may have to interact with local and global suppliers. The supply chain process for the buyer may involve collaborating with the suppliers inventory, shipping, and billing systems. Implementing such a process that spans multiple systems is quite a challenge. One has to know how to interact with the systems as each of the systems may have its own programming interface. This pushes up the complexity of integration and hence the cost.

The IT industry has been battling the problem of managing distributed processes for quite sometime. One way to solve the integration problem is to make all applications support a common integration standard. It is easier said than done as we have had several software vendors pursuing their own proprietary integration framework and selling their own middleware. Though such middleware is helpful in integrating applications, there are limitations. We have also seen the emergence, as of the 1990s, of distributed computing standards like CORBA and COM. Although they have been successful in their own domains, they have not provided a common integration framework for all the vendors to agree upon.

In the past few years, vendors have realized that the market is well served if handled collectively. The Web services initiative is a set of standards to facilitate easy integration of business artifacts. Web services have a wide following and are being actively supported by all the major software vendors including IBM, Microsoft, Sun, Oracle, SAP, and BEA. Because of the wide support from the industry, Web services are flourishing and are expected to stay around for a long time. In my view, the Web services paradigm is similar to reaching the nirvana in distributed computing.

The Web services paradigm is completely based on XML and consists of several standards including SOAP, UDDI, and WSDL. There are standards designed to address each component of integration. For example, SOAP is a transport- agnostic protocol that lets applications communicate with each other. This book explains important standards of Web services in detail. The Web services model segregates the implementation detail from the description. Because of this, any existing legacy IT asset can be described as a Web service. Once created as Web service, it can be consumed by any other application.

The biggest advantage of Web services is to build applications on the fly by leveraging existing assets. As Web services evolve , you will see most common services will be made available as Web services. This will facilitate the evolution of a service-oriented architecture in which software is available and consumed as service components .

Web services offer several benefits. It promotes reuse. A service component can be used by anyone , anywhere , from any platform. Hence, once created as Web service, it is guaranteed for reuse. Web services offer much-needed flexibility for enterprises as components can be outsourced. Web services lower the barriers to switching. As all Web services conform to common standards, buyers can switch poor suppliers with good ones by simply changing the Web service.

As Web services evolve, CTOs have to be knowledgeable in choosing the right vendors for Web services. Even though Web services vendors conform to common standards, there are differences in how they are implemented. This book provides guidance on how to choose the vendors and on the associated implementation issues.

My recommendation is that you take a serious look at Web services. It is widely supported by the industry and getting popular rapidly . Given the network effect, your business may be soon touched by Web services and you would be forced to think of Web services. If you have not thought about a Web services strategy, it is time to get to know more and this book will help you.

”Chandra Venkatapathy
Market Manager, IBM