http://www.synthtopia.com/content/2015/01/16/new-midi-hd-protocol-has-reached-a-milestone/

‘HD Protocol’ Features:

• Backward compatibility with MIDI 1.0 to ensure wide-spread adoption
• Plug and Play network connectivity over USB and Ethernet for easy integration
• Thousands of Channels for handling large complex systems
• A massive number of high resolution Controllers and Parameters for channels, groups and even individual notes, for unrivalled precision and adaptability to new controller technologies
• Precise Pitch Control and Articulation messages for expanded expressivity
• Time Stamped messaging for accurate timing and tight real-time performance
• Plenty of room for future expansion to eliminate obsolescence