TCNOpen

TCNOpen is an open source initiative which the partner railway industries created with the aim to build in collaboration some key parts of new or upcoming railway standards, commonly known under the name TCN.
TCN (Train Communication Network) is a series of international standards (IEC61375) developed by Working Group 43 of the IEC (International Electrotechnical Commission), specifying a communication system for the data communication within and between vehicles of a train. It is currently in use on many thousands of trains in the world in order to allow electronic devices to exchange information while operating aboard the same train.
TCNOpen follows the Open Source scheme, as the software is jointly developed by participating companies, according to their role, so as to achieve cheaper, quicker and better quality results.

Licenses:
TRDP: MPLv2.0 http://www.mozilla.org/MPL/2.0/
TRDPSpy: GPL http://www.gnu.org/licenses/gpl.html