Routing frames in a shortest path computer network for a multi-homed legacy bridge node

• US 8,125,928 B2
• Filed: 07/24/2009
• Issued: 02/28/2012
• Est. Priority Date: 07/24/2009
• Status: Active Grant

• Current Assignee: Juniper Networks Incorporated
• Original Assignee: Juniper Networks Incorporated
• Inventors: Mehta, Apurva, Mehta, Kumar, Ramanathan, Ramasamy, Sankaran, Krishna, Ramakrishnan, Ramanarayanan, Shenoy, Shiva, Krishna, Gopi
• Primary Examiner(s): Wilson, Robert
• Application Number:
  US12/508,949
• Publication Number:
  US 20110019678A1
• Time in Patent Office: 949 Days
• Field of Search: None
• US Class Current: 370/254
• CPC Class Codes: H04L 12/4625 Single bridge functionality, e.g. connection of two networks over a single bridge
• CPC Class Codes: H04L 45/04 Interdomain routing, e.g. hierarchical routing
• CPC Class Codes: H04L 45/24 Multipath
• CPC Class Codes: H04L 45/245 Link aggregation, e.g. trunking
• CPC Class Codes: H04L 45/66 Layer 2 routing, e.g. in Ethernet based MAN's
• CPC Class Codes: H04L 49/351 for local area network [LAN], e.g. Ethernet switches
• CPC Class Codes: Y02D 30/50 in wire-line communication networks, e.g. low power modes or reduced link rate

Abstract

Methods, apparatus, and products for routing frames in a shortest path computer network for a multi-homed legacy bridge, wherein the network includes a plurality of bridges. At least two of the plurality of bridges operate as edge bridges through which the frames ingress and egress the network. A first edge bridge identifies a legacy bridge nickname for a legacy bridge connected to the network through the first edge bridge and a second edge bridge using active-active link aggregation. The first bridge receives a frame from the legacy bridge and determines, in dependence upon the frame'"'"'s destination node address, an egress bridge nickname for a third bridge through which a destination node connects to the network. The first bridge then adds the legacy bridge nickname and the egress bridge nickname to the frame and routes the frame to the third bridge in dependence upon the egress bridge nickname.

Claims

1. A method of routing frames in a shortest path computer network for a multi-homed legacy bridge node, the computer network including a plurality of bridge nodes, at least two of the plurality of bridge nodes operating as edge bridge nodes through which the frames ingress and egress the computer network, the method comprising steps of:

identifying, by a first edge bridge node, a legacy bridge nickname for the legacy bridge node, wherein the legacy bridge node is connected to the computer network through the first edge bridge node and a second edge bridge node using link aggregation in which at least one of a first link to the first edge bridge node and a second link to the second edge bridge node is active;

receiving, by the first edge bridge node, a frame from the legacy bridge node, wherein the frame specifies a source node address for a source node originating the frame and a destination node address for a destination node to which the frame is transmitted, and wherein the source node is connected to the network through the legacy bridge node and one of the first or the second edge bridge node, and the destination node is connected to the network through a third edge bridge node;

determining, by the first edge bridge node, an egress bridge nickname for the third edge bridge node based on the destination node address;

adding, by the first edge bridge node, the legacy bridge nickname and the egress bridge nickname to the frame; and

routing, by the first edge bridge node, the frame to the third edge bridge node based on the egress bridge nickname.

2. The method of claim 1 wherein the step of adding the legacy bridge nickname and the egress bridge nickname to the frame further comprises a step of adding a vender header to the frame that includes the legacy bridge nickname and the egress bridge nickname.

3. The method of claim 1 wherein the step of routing the frame further comprises steps of:

identifying, based on the egress bridge nickname, a media access control (‘

MAC’

) address for a next bridge node in the network that is on a path from the first edge bridge node to the third edge bridge node;

adding the MAC address for the next bridge node to the frame; and

routing the frame to the next bridge node based on the MAC address.

4. The method of claim 1 wherein the computer network and the edge bridge nodes support a Transparent Interconnection of Lots of Links (‘

TRILL’

) protocol, the legacy bridge nickname conforms to the TRILL protocol, and the egress bridge nickname conforms to the TRILL protocol, and wherein routing the frame comprises routing the frame through the computer network using the TRILL protocol.

5. The method of claim 1 wherein the legacy bridge node does not support Media Access Control (MAC)-in-MAC encapsulation, and wherein routing the frame comprises routing the frame through the computer network with MAC-in-MAC encapsulation.

6. The method of claim 1 further comprising processing, by the first edge bridge node and the second edge bridge node, unicast frames for the legacy bridge node.

7. The method of claim 1 further comprising transmitting, by only one of the first edge bridge node and the second edge bridge node, multicast frames towards the legacy bridge node.

8. A method of routing frames in a shortest path computer network for a multi-homed legacy bridge node, the computer network including a plurality of bridge nodes, at least two of the plurality of bridge nodes operating as edge bridge nodes through which the frames ingress and egress the computer network, the method comprising steps of:

identifying, by a first edge bridge node, a legacy bridge nickname for the legacy bridge node, wherein the legacy bridge node is connected to the computer network through the first edge bridge node and a second edge bridge node using link aggregation in which at least one of a first link to the first edge bridge node and a second link to the second edge bridge node is active;

receiving, by the first edge bridge node, a frame for routing to the legacy bridge node, wherein the frame specifies a source node address for a source node originating the frame and a destination node address for a destination node to which the frame is transmitted, wherein the source node is connected to the network through a third edge bridge node, and the destination node is connected to the network through the legacy bridge node and one of the first edge bride node or the second edge bridge node, and wherein the frame also includes the legacy bridge nickname for the legacy bridge node and an ingress bridge nickname for the third edge bridge node;

removing, by the first edge bridge node, the legacy bridge nickname and the ingress bridge nickname from the frame; and

routing, by the first edge bridge node, the frame to the legacy bridge node for delivery to the destination node.

9. The method of claim 8 wherein the step of removing the legacy bridge nickname and the ingress bridge nickname from the frame further comprises a step of removing a vender header that includes the legacy bridge nickname and the ingress bridge nickname from the frame.

10. The method of claim 8 wherein the computer network and the edge bridge nodes support a Transparent Interconnection of Lots of Links (‘

TRILL’

) protocol, the legacy bridge nickname conforms to the TRILL protocol, and the ingress bridge nickname conforms to the TRILL protocol, further comprising routing the frame through the computer network using the TRILL protocol.

11. The method of claim 8 wherein the legacy bridge node does not support Media Access Control (MAC)-in-MAC encapsulation, further comprising routing the frame through the computer network with MAC-in-MAC encapsulation.

12. An apparatus for routing frames in a shortest path computer network for a multi-homed legacy bridge node, the computer network including a plurality of bridge nodes, at least two of the plurality of bridge nodes operating as edge bridge nodes through which the frames ingress and egress the computer network, the apparatus operating as a first edge bridge node, the apparatus comprising:

a computer memory that stores data; and

a processor configured to;

identify a legacy bridge nickname for the legacy bridge node, wherein the legacy bridge node is connected to the computer network through the first edge bridge node and a second edge bridge node using link aggregation in which at least one of a first link to the first edge bridge node and a second link to the second edge bridge node is active,

receive a frame from the legacy bridge node, wherein the frame specifies a source node address for a source node originating the frame and a destination node address for a destination node to which the frame is transmitted, and wherein the source node is connected to the network through the legacy bridge node and one of the first edge bridge node or the second edge bridge node, and the destination node is connected to the network through a third edge bridge node,

determine an egress bridge nickname for the third edge bridge node based on the destination node address,

add the legacy bridge nickname and the egress bridge nickname to the frame, and

route the frame to the third edge bridge node based on the egress bridge nickname.

13. The apparatus of claim 12 wherein the processor is configured to add a vender header to the frame that includes the legacy bridge nickname and the egress bridge nickname.

14. The apparatus of claim 12 wherein the processor is configured to:

identify, based on the egress bridge nickname, a media access control (‘

MAC’

) address for a next bridge node in the network that is on a path from the first edge bridge node to the third edge bridge node;

add the MAC address for the next bridge node to the frame; and

route the frame to the next bridge node based on the MAC address.

15. The apparatus of claim 12 wherein the computer network, the second edge bridge node, and the apparatus operating as the first edge bridge node support a Transparent Interconnection of Lots of Links (‘

TRILL’

) protocol, the legacy bridge nickname conforms to the TRILL protocol, and the egress bridge nickname conforms to the TRILL protocol, and wherein the processor is configured to route the frame through the computer network using the TRILL network.

16. The apparatus of claim 12 wherein the legacy bridge node does not support Media Access Control (MAC)-in-MAC encapsulation, and wherein the apparatus operating as the first edge bridge node supports MAC-in-MAC encapsulation, and the processor is configured to route the frame through the computer network using MAC-in-MAC encapsulation.

17. The apparatus of claim 12 wherein the processor is configured to process unicast frames for the legacy bridge node.

18. The apparatus of claim 12 wherein the processor is configured to transmit multicast frames towards the legacy bridge node.

19. An apparatus for routing frames in a shortest path computer network for a multi-homed legacy bridge node, the computer network including a plurality of bridge nodes, at least two of the plurality of bridge nodes operating as edge bridge nodes through which the frames ingress and egress the computer network, the apparatus operating as a first edge bridge node, the apparatus comprising:

a computer memory that stores data; and

a processor configured to;

identify a legacy bridge nickname for the legacy bridge node, wherein the legacy bridge node is connected to the computer network through the first edge bridge node and a second edge bridge node using link aggregation in which at least one of a first link to the first edge bridge node and a second link to the second edge bridge node is active,

receive a frame for routing to the legacy bridge node, wherein the frame specifies a source node address for a source node originating the frame and a destination node address for a destination node to which the frame is transmitted, wherein the source node is connected to the network through a third edge bridge node, and the destination node is connected to the network through the legacy bridge node and one of the first edge bridge node or the second edge bridge node, and wherein the frame also including includes the legacy bridge nickname for the legacy bridge node and an ingress bridge nickname for the third edge bridge node,

remove the legacy bridge nickname and the ingress bridge nickname from the frame, and

route the frame to the legacy bridge node for delivery to the destination node.

20. The apparatus of claim 19 wherein the processor is configured to remove a vender header that includes the legacy bridge nickname and the ingress bridge nickname from the frame.

21. The apparatus of claim 19 wherein the computer network, the second edge bridge node, and the apparatus operating as the first edge bridge node support a Transparent Interconnection of Lots of Links (‘

TRILL’

) protocol, the legacy bridge nickname conforms to the TRILL protocol, and the ingress bridge nickname conforms to the TRILL protocol, wherein the processor is configured to route the frame through the computer network using the TRILL protocol.

22. A non-transitory computer-readable medium for routing frames in a shortest path computer network for a multi-homed legacy bridge node, the computer network including a plurality of bridge nodes, at least two of the plurality of bridge nodes operating as edge bridge nodes through which the frames ingress and egress the computer network, the computer-readable medium encoded with instructions that when executed cause one or more processors in a first edge bridge node to:

identify a legacy bridge nickname for a legacy bridge node, wherein the legacy bridge node is connected to the computer network through the first edge bridge node and a second edge bridge node using link aggregation in which at least one of a first link to the first edge bridge node and a second link to the second edge bridge node is active;

receive a frame from the legacy bridge node, wherein the frame specifies a source node address for a source node originating the frame and a destination node address for a destination node to which the frame is transmitted, and wherein the source node is connected to the network through the legacy bridge node and one of the first edge bridge node or the second edge bridge node, and the destination node is connected to the network through a third edge bridge node;

determine an egress bridge nickname for the third edge bridge node based on the destination node address;

add the legacy bridge nickname and the egress bridge nickname to the frame; and

route the frame to the third edge bridge node based on the egress bridge nickname.

23. The non-transitory computer-readable medium of claim 22 wherein the instructions cause the one or more processors to add a vender header to the frame that includes the legacy bridge nickname and the egress bridge nickname.

24. The non-transitory computer-readable medium of claim 22 wherein the instructions cause the one or more processors to:

identify, based on the egress bridge nickname, a media access control (‘

MAC’

) address for a next bridge node in the network that is on a path from the first edge bridge node to the third edge bridge node;

add the MAC address for the next bridge node to the frame; and

route the frame to the next bridge node based on the MAC address.

25. The non-transitory computer-readable medium of claim 22 wherein the computer network and the edge bridge nodes support a Transparent Interconnection of Lots of Links (‘

TRILL’

) protocol, the legacy bridge nickname conforms to the TRILL protocol, and the egress bridge nickname conforms to the TRILL protocol, wherein the instructions cause the one or more processors to route the frame through the computer network using the TRILL protocol.

26. The non-transitory computer-readable medium of claim 22 wherein the legacy bridge node does not support Media Access Control (MAC)-in-MAC encapsulation, wherein the instructions cause the one or more processors to route the frame through the computer network using MAC-in-MAC encapsulation.

27. The non-transitory computer-readable medium of claim 22 further comprising instructions that cause the one or more processors to process unicast frames for the legacy bridge node.

28. The non-transitory computer-readable medium of claim 22 further comprising instructions that cause the one or more processors to transmit multicast frames towards the legacy bridge node.

29. A non-transitory computer-readable medium for routing frames in a shortest path computer network for a multi-homed legacy bridge node, the computer network including a plurality of bridge nodes, at least two of the plurality of bridge nodes operating as edge bridge nodes through which the frames ingress and egress the computer network, the computer-readable medium encoded with instructions that when executed cause one or more processors in a first edge bridge node to:

identify a legacy bridge nickname for a legacy bridge node, wherein the legacy bridge node is connected to the computer network through the first edge bridge node and a second edge bridge node using link aggregation in which at least one of a first link to the first edge bridge node and a second link to the second edge bridge node is active;

receive a frame for routing to the legacy bridge node, wherein the frame specifies a source node address for a source node originating the frame and a destination node address for a destination node to which the frame is transmitted, wherein the source node is connected to the network through a third edge bridge node, and the destination node is connected to the network through the legacy bridge node and one of the first edge bridge node or the second edge bridge node, and wherein the frame also includes the legacy bridge nickname for the legacy bridge node and an ingress bridge nickname for the third edge bridge node;

remove the legacy bridge nickname and the ingress bridge nickname from the frame; and

route the frame to the legacy bridge node for delivery to the destination node.

30. The non-transitory computer-readable medium of claim 29 wherein the instructions cause the one or more processors to remove a vender header that includes the legacy bridge nickname and the ingress bridge nickname from the frame.

31. The non-transitory computer-readable medium of claim 29 wherein the computer network and the edge bridge nodes support a Transparent Interconnection of Lots of Links (‘

TRILL’

) protocol, the legacy bridge nickname conforms to the TRILL protocol, and the ingress bridge nickname conforms to the TRILL protocol, further comprising instructions that cause the one or more processors to route the frame through the computer network using the TRILL protocol.

32. The non-transitory computer-readable medium of claim 29 wherein the legacy bridge node does not support Media Access Control (MAC)-in-MAC encapsulation, further comprising instructions that cause the one or more processors to route the frame through the computer network using MAC-in-MAC encapsulation.