Research on the application of cross-domain VPN technology based on MPLS BGP

In order to support the exchange of VPN routing information between operators, it is necessary to extend the existing protocols and modify the MPLS VPN architecture to provide an interconnection model that is different from that provided by the basic MPLS VPN architecture, that is, the BGP-based cross-domain MPLS VPN so that routing prefix and label information can be traversed across the interoperator link.This paper introduces the conceptual model of MPLS VPN based on BGP, analyzes the working principle of MPLS BGP VPN in depth, and compares the current mainstream BGP-based three types (VPN-OptionA, VPNOptionB, and VPN-OptionC) from the aspects of data transmission methods, advantages and disadvantages. The cross-domain MPLS VPN solution, combined with the actual situation of the operator’s network, simulates the implementation of the MPLS BGP cross-domain VPN of VPNOptionC. The results show that the tunnel established by this method can effectively solve the address conflict, mutual access control and data isolation of different VPN users. It can better meet the needs of large-scale operator network cross-domain construction network.