My beef with airplay and pretty much every other Zeroconf based service is that they require weird stuff to work across subnets. Here I isolate every “IOT” device specially the ones that potentially has a phone home capability into a separate network. The wireless network is also segregated and routed. To make everything Zeroconf/Bonjour work I have to create lots of SRV, PTR and TXT records in my internal DNS which is a Samba4 AD. This document http://www.grouplogic.com/Knowledge/PDFUpload/Info/WanBonjou... is great to setup the basics but you will have to find out the specific RR for each type of service.