Communicating with a control plane using a forwarding information format and control plane processing of packets devoid of a virtual switch identifier

• US 8,199,750 B1
• Filed: 12/18/2007
• Issued: 06/12/2012
• Est. Priority Date: 12/18/2007
• Status: Active Grant

• Current Assignee: World Wide Packets, Inc. (Ciena Corporation)
• Original Assignee: World Wide Packets, Inc. (Ciena Corporation)
• Inventors: Schultz, Andrew Patrick, Bly, Keith Michael, Fromm, Kelly Donald, Weaver, Dennis Lee, Gilson, David Henry
• Primary Examiner(s): Sheikh, Ayaz
• Assistant Examiner(s): Weidner, Timothy J
• Application Number:
  US11/958,897
• Time in Patent Office: 1,638 Days
• Field of Search: None
• US Class Current: 370/389
• CPC Class Codes: H04L 49/70 Virtual switches

Abstract

Packet switch operating methods and packet switches receive a plurality of packets using a forwarding plane of the packet switch. Each packet of the plurality conforms to a different one of a plurality of forwarding information formats. The methods and packet switches modify each packet of the plurality to conform to a common forwarding information format instead of a respective one of the plurality of forwarding information formats and forward the modified packets of the plurality to a control plane of the packet switch.

Claims

1. A packet switch operating method comprising:

using forwarding circuitry of the packet switch, receiving a plurality of Ethernet packets comprising Ethernet source addresses and Ethernet destination addresses from one or more first devices distinct from the packet switch, each Ethernet packet of the plurality conforming to a different one of a plurality of forwarding information formats;

the forwarding circuitry determining that a first subset of the received Ethernet packets of the plurality are to be forwarded to control circuitry of the packet switch instead of to ports of the packet switch;

the forwarding circuitry forwarding a second subset of the received Ethernet packets of the plurality to the ports without forwarding the second subset of the received Ethernet packets to the control circuitry;

the ports transmitting the second subset of the received Ethernet packets to one or more second devices connected to the packet switch via the ports;

the forwarding circuitry modifying each Ethernet packet of the first subset to conform to a common forwarding information format instead of a respective one of the plurality of forwarding information formats without modifying Ethernet source addresses or Ethernet destination addresses of the Ethernet packets of the first subset;

the forwarding circuitry forwarding the modified Ethernet packets of the first subset to the control circuitry of the packet switch; and

the control circuitry taking an action influencing a behavior of the forwarding circuitry based on the modified Ethernet packets.

2. The method of claim 1 wherein each Ethernet packet of the plurality is associated with a different one of a plurality of virtual switches of the forwarding circuitry.

3. The method of claim 1 wherein each packet of the plurality is associated with a common virtual switch but with a different one of a plurality of virtual interfaces associated with the common virtual switch.

4. The method of claim 1 wherein each of the forwarding information formats of the plurality has a different bit length.

5. The method of claim 1 wherein the common forwarding information format consists of an Ethernet destination address field and an Ethernet source address field.

6. The method of claim 1 wherein the plurality of Ethernet packets comprises a first plurality of Ethernet packets and further comprising:

in response to the forwarding circuitry forwarding the modified Ethernet packets of the first subset to the control circuitry, the control circuitry sending a second plurality of Ethernet packets from the control circuitry to the forwarding circuitry, each packet of the second plurality conforming to the common forwarding information format;

using the forwarding circuitry, modifying each packet of the second plurality to conform to a different one of the plurality of forwarding information formats; and

the forwarding circuitry forwarding the modified packets of the second plurality to the ports.

7. The method of claim 1 wherein the forwarding circuitry is connected to the ports and the control circuitry connected to the forwarding circuitry, but is not connected to the ports.

8. The method of claim 1 further comprising the forwarding circuitry forwarding some Ethernet packets of the first subset to both the ports and the control circuitry.

9. A packet switch operating method comprising:

using a forwarding plane of the packet switch, receiving an Ethernet packet comprising forwarding information, an Ethernet source address, and an Ethernet destination address from a device distinct from the packet switch, the forwarding plane being configured to forward the Ethernet packet to one or more ports of the packet switch and/or to a control plane of the packet switch based on the forwarding information;

using the forwarding plane, determining that the Ethernet packet is to be forwarded to the control plane;

subsequent to the determining, the forwarding plane modifying the Ethernet packet to have a particular forwarding information format without modifying the Ethernet source address or the Ethernet destination address;

providing the modified Ethernet packet to the control plane; and

the control plane taking an action influencing a behavior of the forwarding circuitry based on the modified Ethernet packet.

10. The method of claim 9 wherein the packet comprises a first Ethernet packet and prior to the modifying, the forwarding information of the first Ethernet packet is arranged in an original forwarding information format different than the particular forwarding information format and further comprising:

using the forwarding plane, receiving a second Ethernet packet comprising second forwarding information different than the first forwarding information, the second forwarding information being arranged in the original forwarding information format;

the forwarding plane modifying the second Ethernet packet to have the particular forwarding information format; and

the forwarding plane providing the modified second Ethernet packet to the control plane.

11. The method of claim 9 wherein the control plane is configured to generate another packet in response to receiving and processing the modified Ethernet packet.

12. The method of claim 9 wherein the control plane is configured to modify a configuration of the forwarding plane based on contents of the modified Ethernet packet.

13. The method of claim 9 wherein the determining comprises determining based on a portion of the Ethernet packet that does not include the forwarding information.

14. The method of claim 9 wherein the Ethernet packet comprises an Institute of Electrical and Electronics Engineers (IEEE) 802.1ag connectivity fault management protocol data unit (CFMPDU), an International Telecommunications Union—

Telecommunications (ITU-T) Y.1731 Ethernet OAM packet, or an Internet Group Management Protocol (IGMP) packet.

15. The method of claim 9 wherein the Ethernet packet is addressed to an Internet Protocol interface of the control plane.

16. The method of claim 9 wherein the modifying comprises removing one of a Virtual Local Area Network (VLAN) identifier, a Multiprotocol Label Switching (MPLS) label, or a service instance identifier (I-SID) identifier from the Ethernet packet.

17. A packet switch operating method comprising:

using a forwarding plane of the packet switch, receiving an Ethernet packet from a control plane of the packet switch, the Ethernet packet comprising first forwarding information arranged in a first format, an Ethernet source address, and an Ethernet destination address, and the Ethernet packet being created by the control plane;

using the forwarding plane, modifying the Ethernet packet to comprise second forwarding information arranged in a second format without modifying the Ethernet source address or the Ethernet destination address, the second format being different than the first format and wherein at least a portion of the second forwarding information is not comprised by the first forwarding information; and

using the forwarding plane, forwarding the modified Ethernet packet to at least one port of the packet switch.

18. The method of claim 17 wherein the first forwarding information comprises an Ethernet destination address and an Ethernet source address and prior to the modifying the Ethernet packet is devoid of a VLAN identifier, an MPLS label, and an I-SID.

19. A packet switch operating method comprising:

using a control plane of the packet switch, receiving a first packet from a forwarding plane of the packet switch, the forwarding plane comprising a plurality of virtual switches, the forwarding plane associating the first packet with one virtual switch of the plurality, and the first packet being devoid of an identifier of the one virtual switch;

in response to the receiving of the first packet, using the control plane to form a second packet based on configuration parameters of the one virtual switch, the second packet being devoid of the identifier of the one virtual switch;

using the control plane, sending the second packet to the forwarding plane; and

wherein the virtual switches of the plurality comprise different packet-forwarding domains relative to one another and the packet-forwarding domains are associated with different subsets of a set of ports of the packet switch relative to one another, individual packet-forwarding domains of the plurality being constrained to receive packets from and forward packets to only ports of the subset associated with the individual packet-forwarding domain.

20. The method of claim 19 wherein the one virtual switch comprises a first virtual switch and further comprising:

using the control plane, receiving a third packet from the forwarding plane, the third packet being associated with a different second virtual switch of the plurality and the third packet being devoid of an identifier of the second virtual switch;

in response to the receiving of the third packet, using the control plane to form a fourth packet based on configuration parameters of the second virtual switch, the fourth packet being devoid of the identifier of the second virtual switch; and

using the control plane, sending the fourth packet to the forwarding plane.

21. The method of claim 19 wherein the control plane is unable, based only on the first packet, to determine which of the virtual switches the first packet is associated with.

22. The method of claim 19 further comprising using the forwarding plane, sending a message distinct from the first packet to the control plane informing the control plane that the first packet is associated with the one virtual switch.

23. A packet switch comprising:

ports configured to send and receive packets;

control circuitry; and

forwarding circuitry connected to the ports and to the control circuitry and configured to receive a plurality of Ethernet packets from the ports, each packet of the plurality having a different forwarding information format and comprising an Ethernet source address and an Ethernet destination address;

to modify each of the Ethernet packets of the plurality to have a common forwarding information format instead of the different forwarding information formats without modifying the Ethernet source address or the Ethernet destination address; and

to forward the modified packets of the plurality to the control circuitry wherein the control circuitry is not directly connected to the ports other than via the forwarding circuitry.

24. The packet switch of claim 23 wherein the forwarding circuitry is configured to forward packets received from the control circuitry to one or more of the ports.

25. The packet switch of claim 23 wherein the control circuitry is physically distinct from the forwarding circuitry.