CE dual-homed link protection method in MPLS L3VPN and system thereof

Abstract

The invention discloses a CE dual-homed link protection method in MPLS L3VPN and a system thereof. The method comprises the following steps: ARP items of a target CE are configured on a main PE and a standby PE; the main PE generates an interface FRR relation table of a direct connecting network segment route which reaches the main PE and the target CE; simultaneously, the main PE and the standby PE generate a host route forwarding table according to static ARP items, and the main PE generates a corresponding subnet route forwarding table according to the interface FRR relation table; after detecting that a link state between the main PE and the target CE changes, the main PE switches the interface FRR relation table into a standby path or switches the interface FRR relation table back into a main path, and updates related information in a subnet routing table and a host routing table; after receiving a data flow, the main PE obtains present effective out interface information from the present host route forwarding table or subnet route forwarding table, and forwards the data flow to reach the target CE. By employing the method and the system of the invention, the rapid switching of the data flow can be effectively realized.

Description

technical field [0001] The present invention relates to Multi-Protocol Label Switching (MPLS, Multi-Protocol Label Switching) three-layer virtual private network (L3VPN, Layer 3 Virtual Private Network) technology, in particular to a dual-homing of a user edge device (CE, Customer Edge device) in an MPLS L3VPN Method and system for link protection. Background technique [0002] MPLS L3VPN is a service provider virtual private network (VPN, Virtual Private Network) solution based on a carrier edge router (PE, Provider Edge) L3VPN technology, which uses the border gateway protocol (BGP, Border Gateway Protocol) in the service The provider's backbone network advertises VPN routes, and uses MPLS to forward VPN packets on the service provider's backbone network. The MPLS L3VPN networking mode is flexible, has good scalability, and can easily support MPLS QOS (Quality of Service) and MPLS Traffic Engineering (TE, Traffic Engineering). Therefore, it has been applied more and more....

AI Technical Summary

Problems solved by technology

Among them, any point of failure includes link failure and node failure. However, this protection scheme has certain defects: when the user-side link of the MPLS L3VPN network fails, that is, when the link between PE 1-CE 2 fails, At this time, neither the inner nor outer layer BFD between PE 3 and PE 1 can detect the failure of the link. The main route of L3VPN FRR on PE 3 can only be converged by MP-BGP, and the speed of route update will be very slow. Therefore, During this period, the data flow from CE 1 to CE 2 is still on the main route of L3VPN FRR. When the data flow is forwarded to PE 1, the data flow is discarded due to the failure of the egress link, which will generate a large number of packet loss

Images