Audio Over IP (AOIP) is getting lots of traction within the commercial audio industry. It provides for flexible and high audio quality distribution of audio signals.
Most prominent player is Dante protocol ("Dante Spoken Here")
There are others: RAVENNA, Q-LAN etc.
What can "glue" them together is the AES-67 protocol that can connect the above hardware into one audio network.
Allonis's DMX-208a hardware supports AES67 and can accept 4 analog audio inputs, 4 digital audio inputs, and output 4 analog audio outputs and 4 digital audio output streams.
Example of a simple AVPro Dante network:

Here is a YouTube that describes a basic Dante network