Method for Establishing Tunnel, Method for Allocating Label, Device and Network System

摘要

A network system includes a first Egress PE1, a second Egress PE2, and an Ingress PE3, the PE1, PE2 separately communicate with a CE, and the PE1, PE2 are located in a same redundancy group, and are separately used as primary/backup devices; the PE1, PE2 separately generate a virtual node, where the virtual node has a global unique Router ID in the network system. The virtual node is used as a next hop node of the PE1, PE2; and the PE1, PE2 send link state information to the PE3, so that the PE3 obtains Router IDs of the PE1 and PE2, a Router ID of the virtual node, and the link state information of the PE1, PE2, and the PE1, PE2 separately allocate a first label to a FEC of a first VPN, and send the first label and the Router ID of the virtual node to the PE3.

主权项

1. A network system, comprising a first egress provider edge device (Egress PE), a second Egress PE and an ingress provider edge device (Ingress PE), wherein the first Egress PE communicates with a customer edge device (CE), and the second Egress PE communicates with the CE,
wherein the first Egress PE and the second Egress PE are located in a redundancy protection group comprising the first Egress PE and the second Egress PE, wherein the first Egress PE is a primary device, and the second Egress PE is a backup device; wherein the first Egress PE comprises a first processor and a first memory storing a first program to be executed in the first processor, the first program including instructions for:
generating a virtual node, wherein the virtual node has a global unique Router ID in the network system, the virtual node is used as a next hop node of the first Egress PE, and the virtual node is used as a next hop node of the second Egress PE;sending a first link state message to the Ingress PE, wherein the first link state message comprises a Router ID of the first Egress PE and state information of a link from the first Egress PE to the virtual node, and the state information of the link from the first Egress PE to the virtual node comprises a cost value M of the link from the first Egress PE to the virtual node and the Router ID of the virtual node; andsending a second link state message to the Ingress PE, wherein the second link state message comprises the Router ID of the virtual node, state information of a link from the virtual node to the first Egress PE and state information of a link from the virtual node to the second Egress PE, the state information of the link from the virtual node to the first Egress PE comprises a cost value N of the link from the virtual node to the first Egress PE and the Router ID of the first Egress PE, and the state information of the link from the virtual node to the second Egress PE comprises a cost value T of the link from the virtual node to the second Egress PE and a Router ID of the second Egress PE; and wherein the second Egress PE comprises a second processor and a second memory storing a second program to be executed in the second processor, the second program including instructions for:
generating the virtual node;sending a third link state message to the Ingress PE, wherein the third link state message comprises the Router ID of the second Egress PE and state information of a link from the second Egress PE to the virtual node, and the state information of the link from the second Egress PE to the virtual node comprises a cost value S of the link from the second Egress PE to the virtual node and the Router ID of the virtual node; andsending a fourth link state message to the Ingress PE, wherein the fourth link state message comprises the Router ID of the virtual node, the state information of the link from the virtual node to the first Egress PE and the state information of the link from the virtual node to the second Egress PE, the state information of the link from the virtual node to the first Egress PE comprises the cost value N of the link from the virtual node to the first Egress PE and the Router ID of the first Egress PE, and the state information of the link from the virtual node to the second Egress PE comprises the cost value T of the link from the virtual node to the second Egress PE and the Router ID of the second Egress PE, wherein N and T are maximum cost values in an Interior Gateway Protocol (IGP), and S and M satisfy groups (1) or (2):{Sxy4+S>Sxy3+MandC34+S>M(1)wherein Px is any neighboring node of the first Egress PE, Pxy is any neighboring node of Px in a network excluding the first Egress PE, Sxy3 is a cost value of a shortest path from Pxy to the first Egress PE, Sxy4 is a cost value of a shortest path from Pxy to the second Egress PE, and C34 is a cost value of a shortest path from the first Egress PE to the second Egress PE; and
X+M