FEC IN DETERMINISTIC CONTROL SYSTEMS OVER GIGABIT ETHERERNET
Cesar Prados Boda, T. Fleck · 2010
Forward Error Correction (FEC) is a technique for recovering from bit errors and frame losses in real-time network applications. Classic recovering strategies, like TCP retransmission, are not suitable due to delay, timing and bandwidth constraints. In this paper, we introduce the FEC technique in a novel deterministic fieldbus, White Rabbit [1] (WR). WR is developed over frame-based computer networking technology, Gigabit Ethernet, GbE. WR provides an effective and resilient way to serve as a deterministic data transfer medium and to interconnect large distributed systems, like Control Systems for Particle Accelerators. The reliability of WR falls on the FEC, which provides the means to guarantee that only one control message per year will be lost or irretrievable as a result of the Bit Error Rate of the physical medium (fiber optic or copper). We propose in this paper a FEC base on LDPC [2], and tailored for broadcast communication in switched networks over noisy channels without retransmission.