In recent years,large video services such as 4K and VR/AR have matured，the large-scale commercial use of 5G wireless networks,government and enterprise lines is developing in the direction of broadbandization,popularization and diversification.Data center construction is also progressing rapidly.The development of these new services continues to challenge the current bearer network and promote the transformation of the network.It demands massive bandwidth,ultra-low latency,multi-service bearer,and safety and reliability for the bearer network.