This paper studies a new communication media-independent redundant communication failure detection and switching mechanism. It adopts a unified network failure criterion both on the recipient and sender to analyze the redundant data status data which is encapsulated in the user data telegram, gathers the communication status of the dual channels, and achieves some functions including fault detection, fault diagnosis, network channel switch. The experimental data of HCM30000 system in Xiluodu – Zhexi ±800 kV HVDC project shows that the software control strategy has a low cost, high reliability and easy migration characteristics, and it has an important application value for large industrial control system of dual systems and dual network channels redundancy communication management.