There is no "networking" between them like in the sense of the MiVO Intertel networking or MiVB cluster networking... but you can have SIP trunks between them and route calls using ARS on the different systems. It's a pain, did it once and probably won't do it again... and if the customer is used to the MiVO networking, it's very annoying they can't have any of the features like BLF's from remote systems, users in groups on other systems, etc.