Method for realizing identical subnet communication for MPLS three-layer virtual special net

Abstract

The method includes following steps: (1) first consumer equipment CE1 sends ARP proxy request with destination address being as IP address of second consumer equipment CE2 to the connected first provider equipment PE1; (2) through sending ARP responses, PE1 informs CE1 the MAC address of interface hardware connected to CE1; (3) looking up label forwarding table, through static route setup by PE1 in advance, and MPLS three layers virtual private network L3VPN, CE1 forwards data packet sent by CE1 to second provider equipment PE2; (4) PE2 sends data packet sent from PE1 to CE2. The invention realizes intercommunication among VPN consumers in same IP sub network distributed at different sites in MPLS L3VPN network.

Description

technical field [0001] The invention relates to the technical field of computer network communication, in particular to a method for realizing communication on the same subnet in a multi-protocol label switching (Multi-Protocol Label Switching, MPLS) three-layer virtual private network (L3VPN). Background technique [0002] Multi-Protocol Label Switching (MPLS) technology has become one of the mainstream technologies of IP (Internet Protocol) bearer network. The IP bearer network realizes the isolation of multi-service and multi-user in the IP bearer network through the use of MPLS-related technologies, such as MPLS VPN technology. MPLS VPN involves MPLS L3VPN (three-layer virtual private network) and MPLS L2VPN (two-layer virtual private network), etc. , where MPLS L3VPN technology has been deployed in large quantities in operator networks. Typical MPLS L3VPN technology is Border Gateway Protocol (BGP) / MPLS L3VPN defined in RFC2547. BGP / MPLS L3VPN refers to operator edge (P...

AI Technical Summary

Problems solved by technology

[0004] However, if the CEs of Site1, Site2, Site3... of VPN1 users are in the same subnet and need to communicate through the carrier's MPLS L3VPN network, problems will arise immediately.

When PE devices exchange BGP routing information of the same VRF (VPN), if the network IP addresses of the sites in the VPN overlap, the local routing information takes precedence when the PE device calculates the route, and the same routing information as advertised by the remote (other) PEs The BGP routing information of the network segment will not generate the corresponding forwarding table, and the intercommunication between VPN sites will not be realized at this time

[0005] The existing MPLS L2VPN technology can forward packets through the user's link-layer MAC information without caring about the layer-3 IP address information, but in this way, the MPLS L2VPN technology must be redeployed in the operator's network, and the network must be re-planned and adjusted , and the current MPLS L2VPN technology is not as widely deployed as MPLS L3VPN, and some operators' network equipment cannot even support the MPLS L2VPN function, or the technical standards of the supported MPLS L2VPN are not completely consistent, MPLS L2VPN involves a variety of standards, each The standards supported by equipment providers are not necessarily consistent

[0006] To sum up, since the VPN users connected to the Ethernet have the same subnet communication requirements, there will be problems in realizing the mutual communication of the VPN users on the same subnet in the existing MPLS L3VPN network, and the equipment of the existing network does not It must be able to support MPLS L2VPN technology. Deploying MPLS L2VPN requires re-planning and configuring data on the entire network, which increases the load on the network. At present, there are many MPLS L2VPN technical standards, and each equipment provider supports different standards, making deployment difficult.

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