Required Reading for Anyone in the Information Management Business

The book starts with a "celestial warning " from the book of Genesis. This is the story of the tower of Babel where everyone could speak the same language and interoperate easily. From there, the authors build a road to understanding for any professional who wants to learn about the state of the Web services business.

This book is written for a large audience. The first part of the book discusses the business case for Web services. Web services allows you to provide information to the public, or open some aspects of your internal process to your trusted trading partners. Before you even think about exposing your internal processes for automation, you must get your own house in order. This is the first of the "Three Steps to Web Services " , which is "Automate internal systems " . The book shows a familiar "subsystem " in a light-hearted way. We are introduced to "JESSIE " , the "Joint Enhanced Sub-System for Integrating the Enterprise " . The job of the JESSIE subsystem is to integrate between two internal systems. We learn, however, that JESSIE is a human, with all of human's advantages and disadvantages ( "...and just last week she threatened to quit if the cafeteria did not bring back the Oreo ice cream bars. " ).

The second part of the book discusses the technology involved in Web services implementation. This part is for developers and managers who need to know what it takes to develop Web services applications. This includes XML, programming models DOM (Document Object Model) and SAX (Simple API for XML), SOAP (Simple Object Access Protocol), a general-purpose envelope for delivering Web services, and WSDL (Web Services Description Language), a contract language for Web services engagement.

The third part discusses things you need to know as you start planning and implementing your Web services project. This includes a description of various integration models (tightly coupled, loosely coupled, message-based, method-based), Web services frameworks that are already in use, and a helpful chapter on the state of Web services extensions ( "Turning a Protocol into a Framework " ). Such extensions will form building blocks to allow easy implementation of security, routing, reliability, change notification, workflow, and attachments.

Throughout the book, the authors use real-life analogies of Web service technology. For example, in the chapter on SOAP, the authors describe how a company might get their invoice to their customer. It is with a paper document and envelope, sent through the mail. This system works because there are standards that define how an envelope is to be addressed, and international treaties concerning postage rates and other factors. Getting a physical envelope from one place on the planet to another depends upon leveraging the infrastructure that already exists for transportation. The postal system did not need to create roads and trucks, but just added a layer of identification and a routing infrastructure to get things from one place to another. SOAP will be a success because it also places a layer of identification and routing on existing infrastructure for electronic transportation.

This book is much recommended for information technology professionals. It is an accessible, easy-to-read book that covers a lot of territory. Almost every page is illustrated with a helpful diagram to drive home the concept in a clear way. If you need to know about Web services, you need this book. And if you are an IT professional today, you need to know about Web services!