Virtual cluster switching

1. A switch, comprising:

a forwarding module operable to determine an output port for a packet; and

a control module operable to:

receive an identifier for the switch; and

join a virtual cluster switch;

a media access control (MAC) learning module operable to:

learn a source MAC address and a corresponding virtual local area network (VLAN) identifier of an ingress packet associated with a port; and

communicate the learned MAC address, corresponding VLAN identifier, and corresponding port information to a name service.

2. The switch of claim 1 ,

wherein the virtual cluster switch comprises one or more physical switches which are allowed to be coupled in an arbitrary topology; and

wherein the virtual cluster switch operates as one single switch.

3. The switch of claim 1 , wherein while determining the output port for the packet, the forwarding module is operable to make the determination based on an Ethernet protocol.

4. The switch of claim 1 , wherein while determining the output port for the packet, the forwarding module is operable to make the determination based on a Transparent Interconnection of Lots of Links (TRILL) protocol, and wherein the packets is encapsulated in a TRILL header.

5. The switch of claim 1 , wherein the identifier is based on a Fibre Channel (FC) switch domain ID.

6. The switch of claim 1 , wherein the control module is further operable to maintain a copy of configuration information for the virtual cluster switch.

7. The switch of claim 6 , wherein the configuration information for the virtual cluster switch indicates a respective switch identifier assigned to a respective physical switch in the virtual cluster switch.

8. The switch of claim 1 , wherein the forwarding module is further operable to query the name service based on a received packet's destination MAC address and corresponding VLAN information.

9. A switching system, comprising:

a plurality of switches configured to transport packets using a first protocol;

a control module residing on a respective switch;

wherein the control module runs a control plane based on a second protocol;

wherein the plurality of switches are allowed to be coupled in an arbitrary topology;

wherein the control module configures the respective switch within the switching system based on the control plane; and

wherein the switching system operates as a single Ethernet switch; and

a media access control (MAC) learning module residing on the respective switch and operable to:

learn a source MAC address and a corresponding virtual local area network (VLAN) identifier of an ingress packet associated with a port; and

communicate the learned MAC address, corresponding VLAN identifier, and corresponding port information to a name service.

10. The switching system of claim 9 , wherein a respective switch in the switching system receives an identifier based on the control plane.

11. The switching system of claim 10 , wherein the identifier is based on an FC switch domain ID.

12. The switching system of claim 11 ,

wherein the packets are transported between switches based on a TRILL protocol; and

wherein the respective switch is assigned a TRILL RBridge identifier that corresponds to the FC switch domain ID.

13. The switching system of claim 9 , wherein a respective switch maintains a copy of configuration information of all the switches in the switching system.

14. The switching system of claim 9 , further comprising the name service which maintains records of MAC addresses and VLAN information learned by a respective switch.

15. A method performed by a switch, comprising:

encapsulating a packet based on a first protocol;

receiving an identifier for the switch based on a second protocol;

joining a virtual cluster switch;

learning a source MAC address and a corresponding VLAN identifier of an ingress packet associated with a port; and

communicating the learned MAC address, corresponding VLAN identifier, and corresponding port information to a name service.

16. The method of claim 15 , wherein the identifier assigned to the Ethernet switch is based on an FC switch domain ID.

17. The method of claim 15 , further comprising maintaining a copy of configuration information for the virtual cluster switch.

18. A switch means, comprising:

a communication means for encapsulating packets based on a first protocol;

a control means for running a control plane based on a second protocol;

a switch means for forming an Ethernet switch based on the control panel;

a receiving means for receiving an identifier for the Ethernet switch;

a joining means for joining a virtual cluster switch via the control plane; and

a MAC learning means for learning a source MAC address and a corresponding VLAN identifier of an ingress packet associated with a port and communicating the learned MAC address, corresponding VLAN identifier, and corresponding port information to a name service.

19. The switch of claim 1 , wherein the identifier for Ethernet switch is a TRILL RBridge identifier.

20. The switch of claim 1 , wherein the first protocol is a Multi-Protocol Label Switch (MPLS) protocol.

21. The switch of claim 1 , wherein while determining the output port for the packet, the forwarding module is operable to perform a lookup using the name service, receive an egress switch identifier from the name service, and determine the output port corresponding to the egress switch identifier.

22. The switch of claim 2 , wherein the physical switches in the virtual cluster switch are allowed to be coupled in a mesh topology.

23. The switching system of claim 9 , wherein the packets are transported between switches based on an MPLS protocol.

24. The switching system of claim 9 , wherein the switches are allowed to be coupled in a mesh topology.

25. The switching system of claim 9 , wherein the name service can be queried to return an egress switch identifier based on a packet's destination MAC address, and wherein the egress switch identifier can be used to determine an output port for the packet.

26. The method of claim 15 , wherein the first protocol is based on a TRILL protocol.

27. The method of claim 15 , wherein the identifier is a TRILL RBridge identifier.

28. The method of claim 15 , wherein the first protocol is based on an MPLS protocol.

29. The method of claim 15 , further comprising querying the name service with a packet's destination MAC address, receiving a corresponding egress switch identifier from the name service, and determining an output port for the packet based on the egress switch identifier.