Queue-based technology is an underrepresented but powerful way to exchange data and events between disconnected clients. WCF has full support for Microsoft's queuing implementation (MSMQ) and BizTalk has an adapter specifically targeted at the netMsmqBinding WCF binding.
Why introduce yet another layer in your service communication? BizTalk has queuing logic, so what benefit do we get by having our service client send a message to an external queue that BizTalk acts upon? First of all, you get delivery assurance in the case of the service being offline. As you are not travelling over an inherently unreliable transport like HTTP, you can be confident that your message will arrive only once at its destination because of the intermediary queue. Also, a queue enables you to implement a level of soft throttling by allowing the queue to get pummeled by inbound requests but allow the service to process them at its leisure.
What we will demonstrate here...