I think this is something like Yamaha Multicast. It is a Sony proprietary streaming system that only streams from Sony devices to Sony devices, and only Audio. I'm not sure that it cares about the source of the audio, only that it has a wired or wireless network connection by which the device can communicate wit each other.
It's Sonys version of the likes of Apple's AirPlay and as said, Yamaha's multicast.
I don't think the link's explanation is not ambiguous at all. Pretty clear if you ask me. It says what it does and what is needed to do it. You just have to check whether your device supports it. Which In your case sounds like a Avr since the thread Is about hdmi.