Responsive link for real-time communications

In this paper, we introduce the Responsive Link, a real-time communication protocol for distributed real-time systems, including sensor-actuator networks, ubiquitous computing systems, robot systems, and mechatronic systems. To realize flexible real-time communications, the Responsive Link has many unique features, including priority-based packet preemption (the higher-priority packet overtakes other packets at each node.), separation of data transmission (data link) and event transmission (event link), independent routing of the data link and the event link, packet acceleration/deceleration using priority replacement (packet priority can be changed with a new priority level at each node to accelerate/decelerate packets under distributed control scheme.), prioritized routing (when multiple packets with different priority levels are sent to the same destination, the other route can be set to realize exclusive communication lines or detours.), dynamically variable link speed, hot-plug&play, topology transparent, etc. The Responsive Link is implemented on Responsive Processor and RMT Processors for distributed real-time systems. The Responsive Link is standardized at ISO/IEC JTC1/SC 25 as ISO/IEC 24740:2008.