Multiple AD domains - what XMPP domains to use?

Hi there, a long time since I’ve participated in these forums! My company is running OF 3.5.2, with LDAP (AD) integration, currently just servicing a single AD domain, no federation. Our XMPP domain is domain.internalname.com which causes us problems with external access, we have to use a connection manager on the DMZ for Spark clients, and I don’t think federation over the internet would even work in this configuration.

What I’d like to do is install a new 3.6.5 server (when released!), but do things better with the benefit of experience. What I want to do is implement Openfire across different company regions (different AD domains) and federate. So, I’m trying to get the XMPP domain naming convention correct from the start. I know that the standard XMPP domain naming convention is to use the SMTP domain. However in our case that is difficult, as we ALL use the same SMTP domain, across every region with multiple AD domains.

What would be the best way to implement this - a unique XMPP domain for each AD domain / Openfire install, but externally resolvable? Or is there a way that Openfire can handle a single XMPP domain across different AD domains / Openfire installations?

Any advice appreciated,

Nick