MSDN has released a new article on Principles of Service Design that show patterns for creating a SOA as well as anti-patterns (what NOT to do). The paper is the first in a series and starts with an explanation of the four tenets of services and then covers patterns including document processing and idempotency.

SOA is an architectural approach to creating systems built from autonomous services. With SOA, integration becomes forethought rather than afterthought—the end solution is likely to be composed of services developed in different programming languages, hosted on disparate platforms with a variety of security models and business processes. While this concept sounds incredibly complex it is not new—some may argue that SOA evolved out of the experiences associated with designing and developing distributed systems based on previously available technologies. Many of the concepts associated with SOA, such as services, discovery, and late binding were associated with CORBA and DCOM. Similarly, many service design principles have much in common with earlier OOA/OOD techniques based upon encapsulation, abstraction, and clearly defined interfaces.