(Ha! see what I did there?)
I have a system whereby a server pushes information from a central DB out to many client DBs (cross-domain via internet), and periodically they call services on the server. This has to withstand intermittent connections, ie queue messages.
I've created a development version using duplex MSMQ that I'm trying to apply transport security. From the reading I've done, it appears that:
Are these facts correct? Am I really the only person who needs to secure services that are queued AND cross-domain AND duplex?
You may, in fact, be the only person in the world right now who wants to do this.
Let me embellish.
But that aside, it seems to me your main challenge will be using MSMQ as a secure transport layer over the internet. Although I have never had to do this, here are a couple of articles:
Sorry couldn't be of more help.