Stability site for VPLS multi-homing

• US 9,270,581 B2
• Filed: 08/23/2013
• Issued: 02/23/2016
• Est. Priority Date: 08/24/2012
• Status: Active Grant

• Current Assignee: CenturyLink Intellectual Property LLC (Lumen Technologies, Inc.)
• Original Assignee: CenturyLink Intellectual Property LLC (Lumen Technologies, Inc.)
• Inventors: Guellal, Ahmed, Li, Shaohong
• Primary Examiner(s): Patel, Parth
• Application Number:
  US13/974,132
• Publication Number:
  US 20140056125A1
• Time in Patent Office: 914 Days
• Field of Search: 370/225, 370/401, 370/389, 370/216, 370/220, 370/392, 370/228, 370/235, 370/390, 370/395.53, 370/400, 370/2, 370/17, 370/219, 370/221, 370/224, 370/229, 709/229, 709/233, 709/234, 709/235, 709/26.01
• US Class Current: 1/1
• CPC Class Codes: H04L 12/28 characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks] wireless communication networks H04W ; arrangements for dividing the transmission path H04W40/00
• CPC Class Codes: H04L 12/2856 Access arrangements, e.g. Internet access asynchronous transfer mode networks H04L12/5601; broadband local area networks H04L12/2801; optical access or distribution networks H04Q11/0067; access to open networks H04L12/5691; digital subscriber line end-user equipment and bit-level processing of data on a PSTN-based network H04M11/00; home network gateways H04L12/2834; wireless access networks H04W
• CPC Class Codes: H04L 12/4641 Virtual LANs, VLANs, e.g. virtual private networks [VPN] LAN interconnection over a bridge based backbone H04L12/462; encapsulation techniques H04L12/4633; routing of packets H04L45/00; packet switches H04L49/00; virtual private networks for security H04L63/0272
• CPC Class Codes: H04L 45/28 using route fault recovery
• CPC Class Codes: H04L 45/50 using label swapping, e.g. multi-protocol label switch [MPLS]
• CPC Class Codes: H04L 45/68 Pseudowire emulation, e.g. IETF WG PWE3

Abstract

Novel tools and techniques are described for mitigating data loss during failover in a VPLS multi-homed network. In one aspect, a primary link might be established between a lowest numbered provider edge (“PE”) router in the service provider network and a lowest numbered physical site at customer premises outside the service provider network. A stability site might be established within the service provider network, communicatively coupled to at least the lowest numbered PE router via a primary virtual circuit. The stability site might be designated as the lowest numbered virtual site, which might have a site ID number lower than the lowest numbered physical site. In response to the primary link failing or becoming broken, one or more backup virtual circuits might be established between a plurality of ingress PE routers and a plurality of egress PE routers in the service provider network, without destroying the primary virtual circuit.

Claims

1. A method for mitigating data loss during failover and recovery in a VPLS multi-homed network, the method comprising:

providing a VPLS multi-homed network comprising a first plurality of provider edge (“

PE”

) routers on a first point of presence (“

POP”

) within a service provider network and a second plurality of PE routers on a second POP within the service provider network, the first plurality of PE routers including a first primary PE router, the second plurality of PE routers including a second primary PE router, each of the first plurality of PE routers in network communication with a first set of customer edge (“

CE”

) devices located within one or more customer sites outside of the service provider network and served by the first POP, wherein the first set of CE devices provide access to a plurality of virtual local area networks (“

VLANs”

), wherein a first CE device in the first set of CE devices is assigned a lowest numbered site ID from among the first set of CE devices, each of the second plurality of PE routers in network communication with a second set of CE devices located within a plurality of customer sites outside of the service provider network and served by the second POP, wherein the second set of CE devices provide access to the plurality of VLANs, wherein a second CE device in the second set of CE devices is assigned a lowest numbered site ID from among the second set of CE devices;

establishing a first primary link between the first primary PE router and the first CE device;

establishing a second primary link between the second primary PE router and the second CE device;

establishing a first stability site within the service provider network;

associating the first stability site with a first interface that is configured to remain operational at all times;

communicatively coupling the first stability site to at least the first primary PE router via a first stable virtual circuit;

assigning the first stability site with a first virtual site ID, the first virtual site ID being lower than the site ID assigned to the first CE device;

establishing a second stability site within the service provider network;

associating the second stability site with a second interface that is configured to remain operational at all times;

communicatively coupling the second stability site to at least the second primary PE router via a second stable virtual circuit;

assigning the second stability site with a second virtual site ID, the second virtual site ID being lower than the site ID assigned to the second CE device; and

in response to at least one of the first primary link or the second primary link failing, establishing one or more backup virtual circuits between the first plurality of PE routers and the second plurality of PE routers, without destroying any of the first or second stable virtual circuits.

2. The method of claim 1, wherein establishing the first stability site comprises connecting a first switch to a port of at least the first primary PE router, and wherein establishing the second stability site comprises connecting a second switch to a port of at least the second primary PE router, the first and second switches being located at the service provider network.

3. The method of claim 1, wherein establishing the first stability site and establishing the second stability site comprises establishing a loopback of a plurality of loopbacks at each of the first and second plurality of PE routers, wherein the plurality of loopbacks includes at least one physical loopback, each physical loopback comprising a physical network connection between two ports of each of the first or second plurality of PE routers at which the physical loopback is established.

4. The method of claim 1, wherein establishing the first stability site and establishing the second stability site comprises establishing a loopback of a plurality of loopbacks at each of the first and second plurality of PE routers, wherein the plurality of loopbacks includes at least one virtual loopback, each virtual loopback comprising a logical loopback within each of the first or second plurality of PE routers at which the logical loopback is established.

5. The method of claim 1, wherein the first plurality of PE routers are configured to route data packets from the first set of CE devices using Junos code, based solely on labels in an MPLS header of the data packets, wherein the second plurality of PE routers are configured to route data packets from the second plurality of PE routers to the second set of CE devices using Junos code, based solely on labels in the MPLS header of the data packets.

6. The method of claim 5, wherein the Junos code comprises RFC 4761.

7. The method of claim 1, further comprising establishing one or more primary virtual circuits between the first plurality of PE routers and the second plurality of PE routers, wherein the first primary link, the second primary link, and one of the one or more primary virtual circuits or the one or more backup virtual circuits establishes a bridging connection linking the first set of CE devices with the second set of CE devices to provide access to the plurality of VLANs.

8. A VPLS multi-homed network system, comprising:

a first plurality of provider edge (“

PE”

) routers on a first point of presence (“

POP”

) within a service provider network, the first plurality of PE routers including a first primary PE router, each of the first plurality of PE routers in network communication with a first set of customer edge (“

CE”

) devices located within one or more customer sites outside of the service provider network and served by the first POP, wherein the first set of CE devices provide access to a plurality of virtual local area networks (“

VLANs”

), wherein a first CE device in the first set of CE devices is assigned a lowest numbered site ID from among the first set of CE devices;

a second plurality of PE routers on a second POP within the service provider network, the second plurality of PE routers including a second primary PE router, each of the second plurality of PE routers in network communication with a second set of CE devices located within a plurality of customer sites outside of the service provider network and served by the second POP, wherein the second set of CE devices provide access to the plurality of VLANs, wherein a second CE device in the second set of CE devices is assigned a lowest numbered site ID from among the second set of CE devices;

a first primary link established between the first primary PE router and the first CE device;

a second primary link established between the second primary PE router and the second CE device;

a first stability site communicatively coupled to at least the first primary PE router via a first stable virtual circuit, the first stability site located within the service provider network, the first stability site being associated with a first interface that is configured to remain operational at all times, wherein the first stability site is assigned with a first virtual site ID, the first virtual site ID being lower than the site ID assigned to the first CE device;

a second stability site communicatively coupled to at least the second primary PE router via a second stable virtual circuit, the second stability site located within the service provider network, the second stability site being associated with a second interface that is configured to remain operational at all times, wherein the second stability site is assigned with a second virtual site ID, the second virtual site ID being lower than the site ID assigned to the second CE device; and

one or more backup virtual circuits established between the first plurality of PE routers and the second plurality of PE routers, the one or more backup virtual circuits being established in response to at least one of the first primary link or the second primary link failing, wherein the one or more backup virtual circuits are established without destroying any of the first or second stable virtual circuits.

9. The system of claim 8, wherein the first stability site comprises a stability site established by connecting a first switch to a port of at least the first primary PE router, and wherein the second stability site comprises a stability site established by connecting a second switch to a port of at least the second primary PE router, the first and second switches being located at the service provider network.

10. The system of claim 8, wherein the first stability site comprises a stability site established by creating a first loopback of a plurality of loopbacks at each of the first plurality of PE routers, wherein the second stability site comprises a stability site established by creating a second loopback of the plurality of loopbacks at each of the second plurality of PE routers, wherein the plurality of loopbacks includes at least one physical loopback, each physical loopback comprising a physical network connection between two ports of each of the first or second plurality of PE routers at which the physical loopback is established.

11. The system of claim 8, wherein the first stability site comprises a stability site established by creating a first loopback of a plurality of loopbacks at each of the first plurality of PE routers, wherein the second stability site comprises a stability site established by creating a second loopback of the plurality of loopbacks at each of the second plurality of PE routers, wherein the plurality of loopbacks includes at least one virtual loopback, each virtual loopback comprising a logical loopback within each of the first or second plurality of PE routers at which the logical loopback is established.

12. The system of claim 8, wherein the first plurality of PE routers are configured to route data packets from the first set of CE devices using Junos code, based solely on labels in an MPLS header of the data packets, wherein the second plurality of PE routers are configured to route data packets from the second plurality of PE routers to the second set of CE devices using Junos code, based solely on labels in the MPLS header of the data packets.

13. The system of claim 12, wherein the Junos code comprises RFC 4761.

14. The system of claim 8, further comprising one or more primary virtual circuits established between the first plurality of PE routers and the second plurality of PE routers, wherein the first primary link, the second primary link, and one of the one or more primary virtual circuits or the one or more backup virtual circuits establishes a bridging connection linking the first set of CE devices with the second set of CE devices to provide access to the plurality of VLANs.