mnet is a 32 / 64 bit WinMM MIDI driver originally written in support of TouchDAW in 2013. It supports RTP and multicast network connections while trying to hide the terminology and complexity of Apple's original MIDI network approach.
The driver comes with a small control panel application named 'MIDIHub' where you decide which device sends MIDI to which of the driver's ports.
Control panel overview:
Most UI elements have tooltips and will hopefully be self-explaining.
Connections are made by dragging from source to destination. To unpatch, double-click one end of a patch cord, then click the other.
Networked devices will mostly appear automatically as a result of DNS service lookups and device scans. Find more information in the documentation of the various protocols.
Each of the four MIDI ports can have an associated RTP session active that will be visible to other devices on the network. Clients connecting to such a service will then send to and receive from the MIDI port that the session is bound to.
By default only the first two ports run RTP sessions. These will be seen by others as "mhb (NAME_IP) RTP 1 & 2".
You can activate the other two and change the session names that will be announced via the textfield at the top of the editor. All changes only take effect after the OK button has been clicked.
Live Routing & Merged Controllers
Some additional per MIDI port functionality (that you will likely not need) is accessible via the lower button on all of the MIDI ports:
Live Routing when activated will send data that comes from the device(s) patched to this MIDI port not only to mnet's MIDI port, but also to the output selected here. MIDI received on the set input will be merged with what is sent out through the nmet port and will be sent to the connected device(s).
Merged Controller merges data from the set input with data received from connected devices and sends it to the mnet MIDI port. Data that a sequencer sends out through the mnet port will be send to connected devices and to the output port selected here. This is for using TouchDAW in parallel with a hardware controller.
These options are mutually exclusive. You can either have Live Routing or the Merged Controller option active. Not both at a time.
Some global settings are available when you type "Control P (or ,)":
Known issues & quirks
Pro Tools for Windows needs to be run as administrator to use mnet (like you would need to do with all MIDI devices that appear with an "[emulated]" suffix in Pro Tools)
Major Windows updates may clear the driver's registry keys. Fully uninstall and reinstall mnet if no more ports are available after the OS update.
If you still run Windows 7 and only get a blank window in MIDIHub, you probably need to update your Internet Explorer (which brings the HTML rendering engine) to at least version 9. See system requirements.