Remote - Playing and Controlling Devices : About Remote

About Remote
MIDI from control surfaces (keyboards, remote control units etc.) is handled by a protocol called Remote. The Remote protocol allows for seamless integration between Reason and control surface devices. It is basically a mapping system that provides direct hands-on control of parameters for each Reason device - including transport and sequencer track selection!
At the time of this writing, Reason supports a large number of control surfaces and keyboards - the knobs, faders and buttons on the devices are automatically mapped to parameters on each Reason device.
Remote drivers for more control surfaces will be added continuously. Check the Propellerhead web page in case your model isn’t listed on the Preferences - Control Surfaces page.
Remote controlling Reason devices couldn’t be made any simpler. Let Reason automatically look for all available MIDI Input ports on your computer and automatically connect your master keyboard. Or, manually set up your control surface for use with Reason - the program handles the rest!

Remote - Playing and Controlling Devices : About Remote