A disstributed backoff algorithm to support real-time traffic on ethernet
ACM SIGOPS Operating Systems Review
Switched Real-Time Ethernet and Earliest Deadline First Scheduling - Protocols and Traffic Handling
IPDPS '02 Proceedings of the 16th International Parallel and Distributed Processing Symposium
IEEE Transactions on Parallel and Distributed Systems
A time-triggered ethernet (TTE) switch
Proceedings of the conference on Design, automation and test in Europe: Proceedings
IPDPS'06 Proceedings of the 20th international conference on Parallel and distributed processing
Enforcing the timing behavior of real-time stations in legacy bus-based industrial Ethernet networks
Computer Standards & Interfaces
Modular software architecture for flexible reservation mechanisms on heterogeneous resources
Journal of Systems Architecture: the EUROMICRO Journal
Periodic message scheduling on a switched ethernet for hard real-time communication
HPCC'06 Proceedings of the Second international conference on High Performance Computing and Communications
Dynamic real-time channel establishment in multiple access bus networks
Computer Communications
Traffic shaping to reduce jitter in controller area network (CAN)
ACM SIGBED Review - Special Issue on the 24th Euromicro Conference on Real-Time Systems
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Ethernet continues to be one of the most popular LAN technologies. Due to the low price and robustness resulting from its wide acceptance and deployment, there has been an attempt to build Ethernet-based real-time control networks for manufacturing automation.However, it is difficult to build a real-time control network using the standard UDP or TCP/IP and Ethernet, because the Ethernet MAC protocol, the 1-persistent CSMA/CD protocol, has unpredictable delay characteristics. When both real-time (RT) and non-real-time packets are transported over an ordinary Ethernet LAN, RT packets from a node may experience a large delay due to (i) contention with non-RT packets in the originating node and (ii) collision with RT and non-RT packets from the other nodes.To resolve this problem, we designed, implemented, and evaluated adaptive traffic smoothing. Specifically, traffic smoother is installed between the UDP or TCP/IP layer and the Ethernet MAC layer, and works as an interface between them.The traffic smoother first gives RT packets priority over non-RT ones in order to eliminate contention within each local node. Second, it smooths a non-RT stream to reduce collision with RT packets from the other nodes. This traffic smoothing can dramatically decrease the packet-collision ratio on the network. The traffic smoother, installed at each node, regulates the node's outgoing non-RT stream to maintain a certain traffic-generation rate.In order to provide a reasonable non-RT throughput, the traffic-generation rate is allowed to adapt itself to the underlying network load condition. This traffic smoother requires only a minimal change in the OS kernel without any modification to the current standard of Ethernet MAC protocol or the TCP or UDP/IP stack.We have implemented the traffic smoother on both the Linux and the Windows NT platforms, demonstrating significant reduction of the RT packet deadline-miss ratio when both RT and non-RT packets are transported over the same Ethernet. More precisely, installation of the proposed traffic smoother on every node is shown to reduce the RT message deadline-miss ratio by two orders of magnitude under a heavily loaded condition, while lowering the non-RT throughput only by half.