No, in this instance ‘3rd party controllers’ refers to Crestron, AMX or similar control systems that can send/receive custom messages over TCP/IP. One typical application is the integration with other equipment such as light, video etc.
The details of the TCP/IP protocol will be published with firmware V1.5 but for anyone interested, the GLD MIDI TCP protocol offers a good starting point for simple Scene recall or input level / mute control.