Design of NIC Redundancy under Bottom-Layer Driver in VxWorks System

The requirements of common network communication for the reliability of network transmission are low. It can not meet the requirements of real time and high reliability in the industrial control network traffic. For needs of high reliability in industrial control network communications, this paper analyzes the VxWorks operating system and the structure of the network layer network card drivers. By studying network protocols and its interface functions, this design realized NIC redundancy approach in the driver. According to the Intel 82557 network chip, a dual NIC redundant configuration and some specific code is completed. With initializing in the driver, the two NICs are configured as the same MAC address. Using the same IP address, the NIC link status monitoring is completed, and according to the link state, the backup NIC is switched without being detected by the network protocol layer. This design can guarantee the reliability of the network communication to the greatest extent, and then improve the quality of network communication, finally ensure the real-time transmission in the industrial control networks.