FLOODING PACKETS ON A PER-VIRTUAL-NETWORK BASIS

• US 20110299531A1
• Filed: 03/09/2011
• Published: 12/08/2011
• Est. Priority Date: 06/08/2010
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Brocade Communications Systems, Inc. (Broadcom, Inc.)
• Inventors: Yu, Shunjia, Ghanwani, Anoop, Koganti, Phanidhar, Chatwani, Dilip
• Granted Patent: US 9,806,906 B2
• Time in Patent Office: Days
• US Class Current: 370/392
• CPC Class Codes: H04L 12/4625 Single bridge functionality, e.g. connection of two networks over a single bridge
• 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 45/32 Flooding denial of service attacks H04L63/1458
• CPC Class Codes: H04L 45/54 Organization of routing tables
• CPC Class Codes: H04L 45/66 Layer 2 routing, e.g. in Ethernet based MAN's
• CPC Class Codes: H04L 45/745 Address table lookup; Address filtering
• CPC Class Codes: H04L 49/208 Port mirroring
• CPC Class Codes: H04L 49/354 for supporting virtual local area networks [VLAN]
• CPC Class Codes: H04L 63/0272 Virtual private networks

Abstract

Methods and techniques for flooding packets on a per-virtual-network basis are described. Some embodiments provide a method (e.g., a switch) which determines an internal virtual network identifier based on one or more fields in a packet'"'"'s header. Next, the method performs a forwarding lookup operation based on the internal virtual network identifier. If the forwarding lookup operation succeeds, the method can process and forward the packet accordingly. However, if the forwarding lookup operation fails, the method can determine a set of egress ports based on the internal virtual network identifier. Next, for each egress port in the set of egress ports, the method can flood the packet if a virtual network identifier in the packet'"'"'s header is associated with the egress port. Flooding packets on a per-virtual-network basis can substantially reduce the amount of resources required to flood the packet when a forwarding lookup operation fails.

Claims

1. A switch, comprising:

a determining mechanism configured to determine a set of egress ports based on an internal virtual network identifier associated with a packet; and

a flooding mechanism configured to, for each egress port in the set of egress ports, flood the packet over the egress port.

2. The switch of claim 1, wherein the determining mechanism is further configured to determine the internal virtual network identifier based on one or more fields in the packet and optionally a port on which the packet was received.

3. The switch of claim 2, wherein the one or more fields in the header of the packet include a customer VLAN (Virtual Local Area Network) identifier.

4. The switch of claim 2, wherein the one or more fields in the header of the packet include a service provider VLAN (Virtual Local Area Network) identifier.

5. The switch of claim 2, wherein the one or more fields in the header of the packet include a Virtual Private Network (VPN) identifier.

6. The switch of claim 2, wherein the one or more fields in the header of the packet include a MAC (medium access control) address.

7. The switch of claim 1, further comprising a forwarding lookup mechanism configured to perform the forwarding lookup operation based on the internal virtual network identifier.

8. The switch of claim 1, wherein the packet is a TRILL packet, and wherein the virtual network identifier is a Virtual Private Network (VPN) identifier stored in a TRILL option field.

9. The switch of claim 1, wherein packets from different virtual networks are mapped to the internal virtual network identifier.

10. A system, comprising:

a processor; and

a memory storing instructions that when executed by the processor cause the system to perform a method, the method comprising;

determining a set of egress ports based on an internal virtual network identifier associated with a packet; and

for each egress port in the set of egress ports, flooding the packet over the egress port.

11. The system of claim 10, wherein the method further comprises determining the internal virtual network identifier based on one or more fields in the packet and optionally a port on which the packet was received.

12. The system of claim 11, wherein the one or more fields in the header of the packet include a customer VLAN (Virtual Local Area Network) identifier.

13. The system of claim 11, wherein the one or more fields in the header of the packet include a service provider VLAN (Virtual Local Area Network) identifier.

14. The system of claim 11, wherein the one or more fields in the header of the packet include a Virtual Private Network (VPN) identifier.

15. The system of claim 11, wherein the one or more fields in the header of the packet include a MAC (medium access control) address.

16. The system of claim 10, wherein the method further comprises performing the forwarding lookup operation based on the internal virtual network identifier.

17. The system of claim 10, wherein the packet is a TRILL packet, and wherein the virtual network identifier is a Virtual Private Network (VPN) identifier stored in a TRILL option field.

18. The system of claim 10, wherein packets from different virtual networks are mapped to the internal virtual network identifier.

19. A method, comprising:

determining a set of egress ports based on an internal virtual network identifier associated with a packet; and

for each egress port in the set of egress ports, flooding the packet over the egress port.

20. The method of claim 19, further comprising determining the internal virtual network identifier based on one or more fields in the packet and optionally a port on which the packet was received.

21. The method of claim 20, wherein the one or more fields in the header of the packet include one or more of:

a customer VLAN (Virtual Local Area Network) identifier;

a service provider VLAN (Virtual Local Area Network) identifier;

a Virtual Private Network (VPN) identifier; and

a MAC (medium access control) address.

22. The method of claim 19, wherein the method further comprises performing the forwarding lookup operation based on the internal virtual network identifier.

23. The method of claim 19, wherein the packet is a TRILL packet, and wherein the virtual network identifier is a Virtual Private Network (VPN) identifier stored in a TRILL option field.

24. The method of claim 19, wherein packets from different virtual networks are mapped to the internal virtual network identifier.