I would like to look into the possibility to use XMPP as a messaging solution between mutiple servers to effectively have one system where not only users but also the software itself communicates with this system. I know this is possible by the XMPP standard, but the question is which libraries or ready-baked XMPP servers I could use to accomplish this.
It would be necessary to exchange different XML payloads, have a secure connection and get an “ack” when a message has arrived. I read that all this is possible with XMPP extensions or plugins, but all servers and clients I find are focussed on instant messaging and oftentimes do not support any security or acknowlegement related extensions.
Example: imagine software installed on 10 machines to exchange events happening on the hardware and all machines want to be able to display which events happened on the other machines, and on which machine exactly it occurred, in realtime. The software on 5 of the systems is implemented in .NET and the software on the other 5 systems is implemented in Java.
(I looked into OpenFire, but I would like to hear your recommendations)
XMPP pubsub seems to fit your problem space.
It is supported by many (most?) servers (including OpenFire). You can use Smack for your java client implementations and there are several .NET libraries available as well. I am not familiar with them so I won’t recommend one (and don’t know which supports pubsub).