System and method for providing network route redundancy across layer 2 devices

Patent metadata

Field	Value
Publication number	US-9450893-B2
Application number	US-201314060841-A
Country	US
Kind code	B2
Filing date	Oct 23, 2013
Priority date	Apr 16, 2002
Publication date	Sep 20, 2016
Grant date	Sep 20, 2016

Abstract

Systems and methods are described for providing network route redundancy through Layer 2 devices, such as a loop free Layer 2 network having a plurality of switching devices. A virtual switch is coupled to the loop free Layer 2 network, the virtual switch having two or more switches configured to transition between master and backup modes to provide redundant support for the loop free Layer 2 network, the switches communicating their status through use of a plurality of redundancy control packets. The system also includes means for allowing the redundancy control packets to be flooded through the Layer 2 network. The means may include time-to-live data attached to the redundancy control packet which is decremented only when the packets are transferred through devices which are configured to recognize the protocol used in redundancy control packets.

First claim

What is claimed is:

1. A switch for use in a system of switches, the system of switches acting as a virtual switch, the switch comprising:
a memory; and
a plurality of ports, each communicatively coupling the switch to a Layer 2 network,
wherein the switch acts in concert with one or more other switches in the system of switches to provide route redundancy for the Layer 2 network, and
wherein the switch communicates its status to the one or more other switches by sending, via each of the plurality of ports, redundancy control packets to the Layer 2 network, and
wherein the sending causes the redundancy control packets to be:
flooded throughout the Layer 2 network; and
transmitted from the Layer 2 network to the one or more other switches in the system of switches.

2. The switch of claim 1 , wherein each redundancy control packet includes a time-to-live data value, and wherein the time-to-live data value is decremented each time the redundancy control packet is transferred through a switch in the system of switches.

3. The switch of claim 1 , wherein the switch operates in a master mode, a backup mode, and a master confirm mode.

4. The switch of claim 1 , wherein the switch, when operating in a first mode, forwards all network traffic received at the switch and transmits one or more redundancy control packets.

5. The switch of claim 1 , wherein the switch, when operating in a second mode, blocks all network traffic received at the switch except for redundancy control packets.

6. The switch of claim 1 , wherein the switch, when operating in a third mode, blocks all network traffic received at the switch except for redundancy control packets, and transmits one or more redundancy control packets.

7. The switch of claim 1 , wherein each redundancy control packet includes a priority data value, and wherein the switch transitions between a backup mode, a master confirm mode, and a master mode based on priority data values included in redundancy control packets received at the switch and a stored priority data value for the switch.

8. The switch of claim 7 , wherein the stored priority data value is based on a number of live connections between the switch and devices in the Layer 2 network.

9. The switch of claim 8 , wherein the number of live connection is determined by broadcasting health check packets from the switch to the devices.

10. The switch of claim 7 , wherein the stored priority data value for the switch is based on the quality of the live connections.

11. The switch of claim 1 , wherein the switch, when operating in a master mode or a master confirm mode, transitions to a backup mode upon receipt of a redundancy control packet having a priority data value greater than a stored priority data value.

12. The switch of claim 1 , wherein the switch, when operating in a backup mode, transitions to a master mode if no redundancy control packet including a priority data value greater than a stored priority data value is received within a predetermined amount of time.

13. The switch of claim 1 , wherein the switch, when operating in a master confirm mode, transitions to a master mode once a predetermined number of redundancy control packets are transmitted by the switch.

14. The switch of claim 1 , wherein the Layer 2 network is a loop free network.

15. The switch of claim 1 , wherein the switch is a Layer 2 switch.

16. The switch of claim 1 , wherein the switch is communicatively coupled with two or more VLANs in the Layer 2 network.

17. The switch of claim 16 , wherein the switch operates in a plurality of modes, and wherein the switch operates in a different mode with respect to each VLAN in the two or more VLANs.

18. A method performed by a switch in a system of switches, the system of switches acting as a virtual switch, the method comprising:
acting, by the switch, in concert with one or more other switches in the system of switches to provide route redundancy for a Layer 2 network, the switch being communicatively coupled with the Layer 2 network via a plurality of ports; and
communicating, by the switch, its status to the one or more other switches by sending, via each of the plurality of ports, redundancy control packets to the Layer 2 network,
wherein the sending causes the redundancy control packets to be:
flooded throughout the Layer 2 network; and
transmitted from the Layer 2 network to the one or more other switches in the system of switches.

19. A non-transitory computer-readable storage medium having stored thereon program code executable by a switch in a system of switches, the system of switches acting as a virtual switch, the program code comprising:
code that causes the switch to act in concert with one or more other switches in the system of switches to provide route redundancy for the Layer 2 network, the switch being communicatively coupled with the Layer 2 network via a plurality of ports; and
code that causes the switch to communicate its status to the one or more other switches by sending, via each of the plurality of ports, redundancy control packets to the Layer 2 network,
wherein the sending causes the redundancy control packets to be:
flooded throughout the Layer 2 network; and
transmitted from the Layer 2 network to the one or more other switches in the system of switches.

Assignees

• Brocade Comm Systems Inc

Inventors

• Kuo Andrew Tai-Chin
• Hsu Ivy Pei-Shan
• Moncada-Elias Jordi
• Jalan Rajkumar
• Kamat Gurudeep

Classifications

• H04L49/552 Primary

  by ensuring the integrity of packets received through redundant connections · CPC title

• H04L45/76

  Routing in software-defined topologies, e.g. routing between virtual machines · CPC title

• H04L45/18 Primary

  Loop-free operations · CPC title

• H04L45/32

  Flooding (denial of service attacks H04L63/1458) · CPC title

• H04L45/48

  Routing tree calculation · CPC title