Redundancy at a Virtual Provider Edge Node that faces a Tunneling Protocol Core Network for Virtual Private Local Area Network (LAN) Service (VPLS)

• US 20090073989A1
• Filed: 09/19/2007
• Published: 03/19/2009
• Est. Priority Date: 09/19/2007
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Cai, Dezhong, Kobo, Roberto, Sajassi, Ali
• Granted Patent: US 8,077,709 B2
• Time in Patent Office: Days
• US Class Current: 370/395.530
• 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 45/00 Routing or path finding of packets in data switching networks routing or path finding in wireless networks H04W40/00
• CPC Class Codes: H04L 45/48 Routing tree calculation
• CPC Class Codes: H04L 45/50 using label swapping, e.g. multi-protocol label switch [MPLS]
• CPC Class Codes: H04L 45/66 Layer 2 routing, e.g. in Ethernet based MAN's
• CPC Class Codes: H04L 45/76 Routing in software-defined topologies, e.g. routing between virtual machines
• CPC Class Codes: H04L 45/80 Ingress point selection by the source endpoint, e.g. selection of ISP or POP

Abstract

In one embodiment, a method includes receiving configuration data at a particular node of a first set of multiple nodes. The configuration data includes data that indicates a particular zero or more instances for which the particular node is primary among multiple virtual local area network (VLAN) instances to be forwarded. It is determined whether a VLAN indicated in a data packet received at the particular node is included in the particular instances for which the particular node is primary. If so, then the data packet is forwarded. In another embodiment, multiple nodes are configured to perform as a single virtual node, and the single virtual node is configured to forward data packets for the multiple VLAN.

Claims

1. A method comprising:

receiving, at a particular node of a first plurality of nodes, configuration data that includes data that indicates a particular zero or more instances for which the particular node is primary of a plurality of virtual local area network (VLAN) instances; and

determining whether a VLAN indicated in a data packet received at the particular node is included in the particular zero or more instances for which the particular node is primary; and

if it is determined that the VLAN indicated in the data packet is included in the particular one or more instances for which the particular node is primary, then forwarding the data packet.

2. A method as recited in claim 1, wherein:

each node of the first plurality of nodes is a network facing provider edge (NPE) node connected both to a core network that uses a tunneling protocol and an aggregation network, and

the aggregation network includes a second plurality of user facing provider edge (UPE) nodes that communicate with the plurality of VLAN instances.

3. A method as recited in claim 1, wherein the particular zero or more instances for which the particular node is primary is more than zero and fewer than all the plurality of VLAN instances, whereby a VLAN forwarding load is distributed among the first plurality of nodes.

4. A method as recited in claim 1, wherein:

said step of receiving configuration data further comprises receiving configuration data that includes backup node data that indicates a different one or more nodes of the first plurality of nodes; and

said step of forwarding data packets further comprises;

if it is determined that the VLAN indicated in the data packet is not included in the particular zero or more instances for which the particular node is primary, then determining whether the different one or more nodes is active for forwarding the packet VLAN; and

if it is determined that the different one or more nodes is active for forwarding the packet VLAN, then not forwarding the data packet, whereby loops are avoided.

5. A method as recited in claim 4, said step of forwarding data packets further comprising, if it is determined that the different one or more nodes is not active for forwarding the packet VLAN, then forwarding the data packet, whereby resilience is provided against failure.

6. A method as recited in claim 4, said step of forwarding data packets further comprising, exchanging messages with the different one or more nodes to determine different one or more instances for which the different one or more nodes is primary of the plurality of VLAN instances, whereby a VLAN forwarding load is correctly balanced among the particular node and the different one or more nodes of the first plurality of nodes.

7. A method as recited in claim 2, said step of forwarding data packets further comprising, associating each of the particular zero or more instances with a virtual private LAN service (VPLS) and an associated tunnel across the core network, which terminates at the particular node.

8. A method as recited in claim 2, wherein any protocol is used in the aggregation network.

9. A method as recited in claim 8, wherein the protocol used in the aggregation network is a spanning tree protocol (STP) that blocks traffic on redundant network segments between intermediate network nodes;

and, the first plurality of nodes does not process STP control packets.

10. A method as recited in claim 8, wherein the protocol used in the aggregation network is Multiple-Protocol Label Switching without a spanning tree protocol (STP) that blocks traffic on redundant network segments between intermediate network nodes.

11. A method comprising:

connecting directly each node of a first plurality of nodes with every other node of the first plurality of nodes;

executing logic on each node of the first plurality of nodes that causes the first plurality of nodes to perform as a single virtual node with a single network address and media access control (MAC) identifier;

connecting a first network interface on each node of the first plurality of nodes to the same particular node in a core network that uses a tunneling protocol; and

connecting a different second network interface on each node of the first plurality of nodes to a different aggregation network that includes a second plurality of user facing provider edge (UPE) nodes that communicates with a plurality of virtual local area network (VLAN) instance; and

executing logic on the single virtual node for forwarding data packets between the core network and the second plurality of UPE nodes for the plurality of VLAN instances.

12. A method as recited in claim 11, further comprising executing logic for a link aggregation control protocol (LACP) on the particular node in the core network to cause the particular node to bundle all direct connections from the particular node to the first network interface on each node of the plurality of nodes.

13. A method as recited in claim 11, further comprising associating each VLAN instance of the plurality of VLAN instances with a different instance of a virtual private LAN service (VPLS) and an associated set of one or more tunnels across the core network, which tunnels terminate at the single virtual node.

14. A method as recited in claim 11, further comprising executing logic for a link aggregation control protocol (LACP) on each UPE in the aggregation network to bundle links from the UPE to the single virtual node.

15. A method as recited in claim 11, wherein any protocol is used in the aggregation network.

16. A method as recited in claim 15, wherein:

the protocol used in the aggregation network is a spanning tree protocol (STP) that blocks traffic on redundant network segments between intermediate network nodes; and

, the single virtual node does not process STP control packets.

17. A method as recited in claim 15, wherein the protocol used in the aggregation network is Multiple-Protocol Label Switching without a spanning tree protocol (STP) that blocks traffic on redundant network segments between intermediate network nodes.

18. An apparatus comprising:

a plurality of network interfaces that are each configured for communicating a data packet with a packet-switched network;

logic encoded in one or more tangible media for execution, and, when executed, operable for;

receiving configuration data that includes primary data that indicates a particular zero or more instances for which the apparatus is primary of a plurality of virtual local area network (VLAN) instances; and

determining whether a packet VLAN of a data packet received at a network interface of the plurality of network interfaces is included in the particular zero or more instances for which the particular node is primary; and

if it is determined that the packet VLAN is included in the particular one or more instances for which the particular node is primary, then forwarding the data packet through a different interface of the plurality of network interfaces.

19. An apparatus as recited in claim 18, wherein:

a first plurality of the plurality of network interfaces are each configured for communicating a data packet with a core network that uses a tunneling protocol, and

a second plurality of the plurality of network interfaces are each configured for communicating a data packet with an aggregation network that includes a plurality of user facing provider edge (UPE) nodes that communicate with the plurality of VLAN instances.

20. An apparatus as recited in claim 18, wherein the particular zero or more instances for which the apparatus is primary is more than zero and fewer than all the plurality of VLAN instances, whereby a VLAN forwarding load is distributed among a plurality of nodes.

21. An apparatus as recited in claim 18, wherein:

said receiving configuration data further comprises receiving configuration data that includes backup node data that indicates a different one or more nodes on the packet-switched network; and

said forwarding data packets further comprises;

if it is determined that the packet VLAN is not included in the particular zero or more instances for which the apparatus is primary, then determining whether the different one or more nodes is active for forwarding the packet VLAN; and

if it is determined that the different one or more nodes is active for forwarding the packet VLAN, then not forwarding the data packet, whereby loops are avoided.

22. An apparatus as recited in claim 21, said forwarding data packets further comprising, if it is determined that the different one or more nodes is not active for forwarding the packet VLAN, then forwarding the data packet, whereby resilience is provided against failure.

23. An apparatus as recited in claim 19, wherein any protocol is used in the aggregation network.

24. An apparatus comprising:

a first plurality of network interfaces that are each configured for communicating a data packet with an aggregation packet-switched network that includes a plurality of user facing provider edge (UPE) nodes that communicates with a plurality of virtual local area network (VLAN) instances;

a second plurality of network interfaces that are each configured for communicating a data packet with a particular node in a core packet-switched network that uses a tunneling protocol for forwarding data packets for the plurality of VLAN instances;

a plurality of processors, wherein each one of the plurality of processors is connected to a network interface of the first plurality of network interfaces and a network interface of the second plurality of network interfaces and to every other processor in the plurality of processors; and

logic encoded in one or more tangible media for execution on the plurality of processors, and, when executed, operable for

causing the plurality of processors to perform as a single virtual node with a single network address and media access control (MAC) identifier, and

forwarding data packets between the core network and the second plurality of user facing provider edge (UPE) nodes for the plurality of VLAN instances.