Programming WCF Services, 4th Edition

Appendix A. Introduction to Service Orientation

This book is all about designing and developing service-oriented applications using WCF, yet there is considerable confusion and hype concerning what service orientation is and what it means. To make matters worse, most of the vendors in this space equate their definition of service orientation with their products and services. The vendors (Microsoft included) add to the confusion by equating service orientation with high-end Enterprise applications, where handling high scalability and throughput is a must (mostly because they all contend for that market, where the business margins are made).

This appendix presents my understanding of what service orientation is all about and attempts to put it in a concrete context. My take is different from that of the large vendors, but I believe it is more down-to-earth, rooted as it is in trends and the natural evolution of our industry. As you will see, I believe that service orientation is not a breakthrough or a quantum leap of thought, but rather the next gradual step (and probably not the last step) in a long journey that spans decades.

To understand where the software industry is heading with service orientation, you should first appreciate where it came from. After a brief discussion of the history of software engineering and its overarching trend, this appendix defines service-oriented applications (as opposed to mere architecture), explains what services themselves are, and examines ...