Evaluation of high-performance network technologies for ITER

For the fast feedback plasma controllers, ITER's Control, Data Access and Communication system (CODAC) will need to provide a mechanism for hard real-time communication between its distributed nodes.In particular, the ITER CODAC team identified four types of high-performance communication applications. Synchronous Databus Network (SDN) is to provide an ability to distribute parameters of plasma (estimated to about 5000 double-valued signals) across the system to allow for 1 ms control cycles. Event Distribution Network (EDN) and Time Communication Network (TCN) are to allow synchronization of node I/O operations to 10 ns. Finally, the Audio–Video Network (AVN) is to provide sufficient bandwidth for streaming of surveillance and diagnostics video at a high resolution (1024 × 1024) and frame rate (30 Hz).In this article, we present some combinations of common-off-the-shelf (COTS) technologies that allow the above requirements to be met. Also, we present the performances achieved in a practical (though small scale) technology demonstrator, which involved a real-time Linux operating running on National Instruments’ PXI platform, UDP communication implemented directly atop the Ethernet network adapter, CISCO switches, Micro Research Finland's timing and event solution, and GigE audio–video streaming.