Understanding various WCF communication options

David Chappell has written an interesting paper outlining various messaging options available in the .NET Framework 3.5 including WCF channels, RESTful communication and BizTalk Services.  There is also a section on WCF LOB Adapter SDK in this document under the heading - "Communication with line-of-business applications using adapters".  I recommend reading this paper, if you want to get an high level overview of the WCF LOB Adapter SDK.  The paper is called Dealing with Diversity: Understanding WCF Communication Options in the .NET Framework 3.5.