Proceedings on the 13th CISL Winter Workshop Sul-Ak Mountain February 2000 PHYSICAL LAYER REDUNDANCY METHOD FOR FAULT-TOLERANT NETWORKS IN PICNET

In this paper, the physical-layer redundancy method is proposed for the fault-tolerant industrial network. The proposed method consists of the fault detection method and the correction method. The fault detection method uses events created by the state transition in the IEEE 802.4 MAC sublayer and the periodic status frame check for the detection of the fault. The fault correction method corrects the fault with the automatic physical layer switching to the stand-by physical layer due to the event created by the fault detection method. The proposed method is realized with dual physical layers, the Dual Channel Manager for switching and the Redundancy Management Module that has the Fault Detection Sub-module and the Fault Correction Sub-module. As results of the practical implementation, the proposed method guarantees high reliablility and fast fault-correction in PICNET.