I’m currently involved in a project where BizTalk and WCF are used in an application where a web portal has to be coupled with a services oriented back-end application for (among others) performing calculations and proposing an insurance policy with the right monthly fees. WCF is heavily used for both connecting the frontend SharePoint web application to BizTalk as well as connecting the BizTalk Orchestrations with the back-end services. Low latency is a must here, as you can understand. The end-user (an intermediary for this insurance company) does not want to wait for more than 10 seconds to get an insurance offer… (The calculations at this customer are by the way Web Services wrapped Java and Delphi components – but that’s a different story).
I was hired to investigate the performance issues (not really low latency at first!) and one of the things brougth up early was: Why use BizTalk (that seems to be the bottleneck) and not use WF?
The perf issues have been solved and low latency is OK now (also thanks to some tips in “Low Latency” chapter in Professional BizTalk Server 2006), but the question remained: Why BizTalk and not just use WF and WCF?
I was planning to write a blog on that… but I found a really perfect article on this topic that I highly recommend to everyone faced with this question: http://biztalkhotrod.com/Documents/BizTalk%20Smack%20Down%20Full.pdf.