Hi,
I recently wrote a set of small programs for the new Network MIDI 2.0 UDP transport with ALSA sequencer / rawmidi API, based on v1.0 spec. The current version (v0.3) is found at: https://github.com/tiwai/amidi2net
A network server can be invoked simply via: % amidi2net-server and this will create an ALSA sequencer client/port. This ALSA sequencer port can be connected by any other ALSA sequencer programs or devices.
The server opens a UDP port, so that it can be connected by a client on another machine on the net, e.g.: % amidi2net-client -l amidi2net which creates an ALSA sequencer client/port similarly, and this can be connected by other apps, too. After the network connection, server and client can pass the UMP data between them freely, so they work as a bridge or hub for applications on both machines.
Some details are found in README and man pages.
For the builds, you'll need openssl and avahi devel packages. (It allows to build without those, but basic functions will be missing.)
As it's a quite initial version, there can be bugs and subject to change. But the stuff seems working stably.
Feel free to reach me if you find any issues.
thanks,
Takashi