Now that you know a little more about WF, you might be wondering (as many do) what the value of BizTalk is, given the release of WF? We'll now position the two technologies and cover some scenarios where they should be used.
As you've probably already realized from this chapter, WF is incredibly powerful and extensible. However, it's just a foundation for providing workflow in your application. By itself, it is not suitable as an enterprise business process management/workflow tool. Consider the requirement to communicate with a variety of systems during workflow execution. BizTalk provides a wide range of adapters and pipeline components to make this integration process easy.
Of course, you can use it as the basis for such a tool. In fact, the next major release of BizTalk Server (post–BizTalk Server 2006 R2) supposedly will use WF in place of the proprietary BizTalk Orchestration Engine (XLANG). BizTalk itself will then have to provide enterprise-class and scalable runtime services to achieve the sort of performance demanded by customers. A custom WF scheduling service is likely to be required to allow BizTalk to precisely control which threads are available and to implement throttling, for example.
Custom persistence services will need to be developed to provide all the rich features currently available in BizTalk Server. One of the challenges we have with BizTalk Server today concerns low latency, in that the MessageBox ...