Using Switched Ethernet for Hard Real-Time Communication

Previous results on traffic shaping on Switched Ethernet technology demonstrate its practicability and effectiveness for hard real-time communication [Low-latency hard real-time communication over switched ethernet]. The application-to-application delays on a 5-node network were reported to be less than a millisecond with both Fast Ethernet and Gigabit Ethernet technology with a link utilization of 93% and 49%. In this paper we describe directions of research to extend this work, targeting performance bottlenecks we identified in the current design. We present ideas on offloading the traffic shaping process and the receive process into the firmware of a network interface card (NIC) and we refine the one-shot reservation protocol for best-effort traffic.