Abstract: With the continuous increase in the number of users which access to ISP's edge devices,the amount of data needs to be processed has doubled,which causes the edge device to be overloaded,and affects the normal interaction of the virtual private network data constructed by the multi-protocol label switching and the border gateway protocol.At this stage,the MCE,HOPE and SDN solutions all have certain limitations in solving this problem:the MCE mode edge device interface does not support the creation of logical channels,the solution cannot be used;the HOPE mode causes problems such as routing loops;the number of concurrent sessions processed by a single SDN controller in the SDN mode cannot exceed 64 000.In response to the above problems,an edge device optimization solution based on dual-layer virtualization is proposed.This solution includes the following three basic steps:edge device virtualization,virtual private network tunnel establishment,and virtual private network information isolation.On this basis,the solution is optimized from the network model,the construction of the network resource pool and the splitting of the network resource pool.The performance of the solution is evaluated based on the experimental environment,and compared with the virtual private network constructed in the traditional way in terms of packet forwarding rate,manageability,and sca-lability.The analysis results show that the dual-layer virtual solution which is designed to construct a network resource pool can realize the unified scheduling and management of resources,effectively solve the overloaded problem of ISP's edge equipment,and also be an effective solution for building a virtual private network.

Key words: Border gateway protocol, Edge device, Multi-protocol label switching, Virtual private network, Virtualization