WO2018117336A1

WO2018117336A1 - Openflow switch for error recovery, openflow controller and error recovery method

Info

Publication number: WO2018117336A1
Application number: PCT/KR2017/003206
Authority: WO
Inventors: 추현승; 토랏 판카즈빔라오; 라제쉬샬라; 라자 사마드무하마드; 김희진; 양윤정
Original assignee: 성균관대학교산학협력단
Priority date: 2016-12-20
Filing date: 2017-03-24
Publication date: 2018-06-28
Also published as: KR101880222B1; KR20180071659A

Abstract

The present invention comprises: a communication module; a memory having an error recovery program stored therein; and a processor for executing the program, wherein the processor sets, according to an execution of the program, an alternative path corresponding to a flow on the basis of information on component, which corresponds to flow information and error, when the error is detected in the component included in a path corresponding to the flow. The component includes an openflow switch or a link, and the component corresponding to the error has occurred the error during the link corresponding to the openflow switch, in which the processor transfers a packet according to the flow, or the openflow switch transferring the packet according to the flow.

Description

Openflow Switch, Openflow Controller, and Error Recovery Methods for Error Recovery

The present invention relates to an openflow switch, an openflow controller, and an error recovery method for error recovery.

Openflow is an interface standard technology of software definition network (SDN). At this time, the openflow-based network includes an openflow controller and an openflow switch, and performs internal communication using an openflow protocol.

OpenFlow-based networks replace the traditional network structure, which was fixed and closed in hardware, with an open, programmable structure. A key feature of OpenFlow-based networks is the software separation of the control plane that controls and manages existing network equipment. Therefore, OpenFlow-based networks have the advantage that users can build and operate the networks they want, rather than the way they provide.

Openflow based networks include an openflow controller and a plurality of openflow switches. The openflow controller may provide flow information for processing the received packet. The open flow switch processes the packet according to the flow information transmitted by the open flow controller.

In the event of an error in an openflow-based network, the openflow switch can bypass the interrupted flow based on a preset alternate path per flow. Therefore, each openflow switch stores a path corresponding to one or more flows and an alternate path for that path. That is, as the number of flows increases, paths and alternate paths that need to be stored in the openflow switch may increase, resulting in memory overload on the openflow switch.

In this regard, Korean Patent Publication No. 10-1585413 (name of the invention: "Openflow Controller and Disaster Recovery Method for Software-Defined Network-Based Cloud Computing System") is based on live migration of virtual machines included in the loud computing system. Detect live migrated virtual machines, extract forwarding paths corresponding to live migrated virtual machines, update stored forwarding paths based on extracted forwarding paths, and retrieve openflow switches corresponding to extracted forwarding paths Then, a disaster recovery method for updating the forwarding path extracted to the searched open flow switch is disclosed.

The present invention is to solve the above-mentioned problems of the prior art, an open flow switch and an error recovery method in the open flow controller and the open flow switch, which provides an alternative path for error recovery on the path, an alternative path in the open flow controller Provide the method of providing.

However, the technical problem to be achieved by the present embodiment is not limited to the technical problem as described above, and other technical problems may exist.

As a technical means for achieving the above technical problem, an open flow switch for recovering an error according to the first aspect of the present invention includes a communication module, a memory in which an error recovery program is stored, and a processor executing a program. In this case, when an error is detected on a component included in a path corresponding to the flow, the processor sets an alternative path corresponding to the flow based on the information of the flow and the information of the component corresponding to the error according to the execution of the program. The component includes an open flow switch or a link, and a component corresponding to an error is an error in a link corresponding to an open flow switch in which a processor delivers a packet according to a flow or an open flow switch that delivers a packet according to a flow. .

In addition, the open flow controller according to the second aspect of the present invention includes a communication module for performing data communication with a plurality of open flow switches, a memory in which an alternative path generation program is stored, and a processor executing a program stored in the memory. At this time, the processor collects a plurality of flows according to the execution of the program, classifies each flow into a flow group based on the information of the plurality of flows, generates an alternative path corresponding to the flow group, and generates a plurality of open flow switches. Pass the generated alternate path. And the alternate path corresponds to an error in the flow, the error being an error for at least one of the one or more components included in the flow, the component including an openflow switch or link.

An error recovery method in an openflow switch according to a third aspect of the present invention includes detecting an error on a component included in a path corresponding to a flow; And setting an alternative path corresponding to the flow based on the information of the flow and the information of the component corresponding to the error. In this case, the component includes an open flow switch or a link, and a component corresponding to an error is an error in a link corresponding to an open flow switch for delivering a packet according to the flow or an open flow switch for delivering a packet according to the flow. .

The error recovery method in the open flow controller according to the fourth aspect of the present invention includes collecting a plurality of flows and classifying each flow into a flow group based on information of the plurality of flows; Generating an alternate route corresponding to the flow group; And forwarding alternate paths generated by the plurality of openflow switches. At this time, the alternate path corresponds to an error of the flow, the error is an error for at least one of the one or more components included in the flow, and the component includes an openflow switch or link.

According to the present invention, each openflow switch may store alternative paths for flow groups having the same address of the destination without storing alternative paths corresponding to a plurality of flows on the openflow-based network. Therefore, the present invention is efficient because the number of alternative paths stored in each openflow switch can be reduced.

In addition, the present invention can reduce the overload of the open flow controller. Therefore, the present invention can quickly cope with errors that may occur in an openflow-based network.

1 is an exemplary diagram of an openflow based network.

2 is an exemplary diagram of an openflow switch error in an openflow-based network.

3 is an exemplary diagram of a link error of an openflow based network.

4 is an exemplary diagram of an edge component error of an openflow based network.

5 is a block diagram of an openflow switch according to an embodiment of the present invention.

6 is an exemplary diagram of a flow table and a group table according to an embodiment of the present invention.

7 is an exemplary view for explaining an error recovery process for a core component according to an embodiment of the present invention.

8 is an exemplary diagram for describing an error recovery process for an edge component according to an embodiment of the present invention.

9 is a block diagram of an openflow controller according to an embodiment of the present invention.

10 is a flowchart illustrating an error recovery method in an openflow switch according to an embodiment of the present invention.

11 is a flowchart illustrating an error recovery method of an openflow controller according to an embodiment of the present invention.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and like reference numerals designate like parts throughout the specification.

Throughout the specification, when a part is "connected" to another part, this includes not only "directly connected" but also "electrically connected" with another element in between. . In addition, when a part is said to "include" a certain component, this means that it may further include other components, except to exclude other components unless otherwise stated.

Next, a recovery method in a general openflow-based network 100 will be described with reference to FIGS. 1 to 4.

1 is an illustration of an openflow based network 100.

Referring to FIG. 1, the openflow based network 100 may include six

openflow switches

110, 120, 130, 140, 150, and 160. In addition, the openflow-based network 100 may include a first host 170, a second host 171, and a third host 172.

The openflow-based network 100 may include an openflow controller, a destination host, and a source host directly or indirectly connected to six

switches

110, 120, 130, 140, 150, and 160.

The source host may forward the packet to the destination host. In this case, the destination host and the departure host may be the first host 170, the second host 171, and the third host 172. Also, the source host and the destination host may be other hosts not shown in FIG. 1. For example, the source host and the destination host may be, but are not limited to, a server, computer or mobile device.

Each open flow switch may be connected to another open flow switch, an open flow controller, or a host through a predetermined link.

In addition, the openflow based network 100 may include edge components and core components. In this case, the edge component may be directly connected to the destination host or the source host, and may include an edge switch and an edge link.

For example, referring to FIG. 1, the edge switch may be the third open flow switch 130 and the fourth open flow switch 140, and the edge link may be the third open flow switch 130 or the fourth open. It may be a link connected to the flow switch 140.

In addition, the core component delivers a packet received from the source host to another core component or an edge component, and may include a core switch and a core link.

For example, referring to FIG. 1, the core switch may be a first open flow switch 110, a second open flow switch 120, a fifth open flow switch 150, and a sixth open flow switch. In addition, the core link may be a link connected to the first open flow switch 110, the second open flow switch 120, the fifth open flow switch 150, and the sixth open flow switch.

The open flow based network 100 may include a first flow in which the first host 170 or the second host 171 is a destination host, and a second flow in which the third host 172 is a destination host. The optimal path of the first flow may be "first openflow switch 110-> second openflow switch 120-> fourth openflow switch 140". Also, the optimal path of the second flow may be “first open flow switch 110-> second open flow switch 120-> third open flow switch 130”. In this case, the first flow and the second flow may share a link between the first open flow switch 110 and the second open flow. That is, the second open flow switch 120 may serve as a center switch for the first flow and the second flow.

If an error occurs in any of the components included in the openflow-based network 100, each openflow switch included in the openflow-based network 100 may bypass other components based on the bypass path through the openflow controller. Can be.

In this case, the error may be that the open flow switch included in the open flow-based network 100 is powered off or a failure occurs, and thus the packet cannot be received. Alternatively, an error means that an openflow switch included in the openflow-based network 100 is powered off, or a failure occurs, so that a received packet cannot be delivered to another openflow switch or host. Alternatively, the error may be that the link between the two open flow switches is broken, but is not limited thereto.

2 is an exemplary diagram of an open flow switch error of the open flow based network 100.

For example, referring to FIG. 2, an error may occur in the second openflow switch 120 included in the openflow-based network 100. That is, the open flow-based network 100 may include

links

200, 201, and second between the first open flow switch 110 and the second open flow switch 120 based on an error of the second open flow switch 120. The link 210 between the open flow switch 120 and the fourth open flow switch 140 and the link 220 between the second open flow switch 120 and the third open flow switch 130 become unavailable.

The openflow-based network 100 may bypass a failed switch and another switch that is a predetermined hop interval based on an alternate path. For example, the openflow based network 100 may bypass according to a bypass path generated based on a local protection mechanism.

For example, the predetermined hop may be within two hops. Therefore, the first flow may bypass the fourth open flow switch 140 of the second open flow switch 120 and the one-hop interval switch. That is, the path of the first flow may bypass the "first open flow switch 110-> fifth open flow switch 150-> fourth open flow switch 140". In a similar manner, the second flow can bypass the sixth open flow switch 160. That is, the path of the second flow may bypass the "first open flow switch 110-> sixth open flow switch 160-> third open flow switch 130".

3 is an exemplary diagram of a link error of the openflow based network 100.

Referring to FIG. 3, an error may occur in the

links

300 and 301 between the first open flow switch 110 and the second open flow switch 120. Therefore, the path of the first flow may bypass the "first open flow switch 110-> fifth open flow switch 150-> fourth open flow switch 140". In addition, the path of the second flow may bypass the "first open flow switch 110-> sixth open flow switch 160-> third open flow switch 130".

As such, when an error occurs in the core component, the openflow-based network 100 may bypass the failed core component through a bypass path. However, when an error occurs in the edge component, the openflow-based network 100 may not include a switch that is not affected by the error within a predetermined hop number.

4 is an exemplary diagram of an edge component error of the openflow based network 100.

For example, referring to FIG. 4, when an error occurs in the link 400 between the second openflow switch 120 and the fourth openflow switch 140, the openflow-based network 100 may no longer be bypassed. No bypass route found In this case, the open flow controller of the open flow based network 100 may set a backup path to solve the problem of the link 400 in which an error occurs. That is, the second openflow switch 120 is along the backup path until the link 400 between the second openflow switch 120 and the fourth openflow switch 140 is restored. ) May be bypassed by the first open flow switch 110, the fifth open flow switch 150, and the fourth open flow switch 140.

In this case, the conventional openflow-based network 100 may generate a backup path in a reactive manner through the openflow controller included in the openflow-based network 100.

For example, the open flow controller may modify a flow rule for a suspended flow based on a specific open flow switch or a specific link and transmit the modified flow rule according to a preset backup path. At this time, in order to modify the flow rule, the open flow controller should calculate an alternative port corresponding to the flow rule. Therefore, the OpenFlow Controller can receive alternate port information for each OpenFlow switch. The openflow controller may set a bypass node by detecting a port state of each openflow switch based on the received alternate port information and a loss of signal (LOS) signaling mechanism.

The OpenFlow controller can calculate a port that can replace the failed port. After calculating the alternative port, the open flow controller may modify the optimal path rule to transmit the interrupted flow to the preset backup path.

For example, referring back to FIGS. 2 and 3, an error is found in the second open flow switch 120, or an error is detected in the path between the first open flow switch 110 and the second open flow switch 120. If found, the first openflow switch 110, which intends to deliver a packet to the second openflow switch 120, may transmit an abnormality notification message to the openflow controller.

The open flow controller can generate flow modification messages and pass them to the appropriate open flow switches. In this case, the flow modification message may be a message for transmitting a flow in which transmission is interrupted through the second open flow switch 120 and other open flow switches within a predetermined hop number through a predetermined substitute path. That is, the fifth open flow switch 150 may install a flow rule for delivering a packet based on the first flow.

Next, an open flow switch 500 according to an embodiment of the present invention will be described with reference to FIGS. 5 to 8.

5 is a block diagram of an openflow switch 500 according to an embodiment of the present invention.

The openflow switch 500 may allow a packet transmitted from the source host to be delivered to the destination host. In this case, the open flow switch 500 may be directly connected to the source host or the destination host or indirectly through one or more other open flow switches 500.

In addition, the open flow switch 500 may be directly connected to the open flow controller 540 or may be connected through one or more other open flow switches 500.

The open flow switch 500 includes a communication module 510, a memory 520, and a processor 530.

The communication module 510 may perform data communication with the host and the open flow switch 500. In addition, the communication module 510 may perform data communication with the open flow controller 540.

The memory 520 stores an error recovery program. In this case, the memory 520 generally refers to a nonvolatile storage device that maintains stored information even when power is not supplied, and a volatile storage device that requires power to maintain stored information.

The memory 520 also stores a flow table and a group table. The flow table and the group table will be described with reference to FIG. 6.

6 is an exemplary diagram of a flow table and a group table according to an embodiment of the present invention. 6A is an exemplary diagram of a flow table. 6B is an exemplary diagram of a group table.

The flow table stores flow rules as entries.

For example, the flow rule may include a source IP, a destination IP, an entry port, a VLAN ID, and an action. At this time, the source IP may be the same address as the source host IP. In addition, the destination IP may be the same address as the IP of the destination host. In addition, the VLAN ID may be a unique identifier corresponding to the component.

In this case, the component is a concept including an open flow switch 500 and a link. The link means a wired connection or a wireless connection between two open flow switches 500.

The action is defined an action corresponding to the flow rule. For example, referring to FIG. 6A, the action may include a group ID that can be used to deliver a packet.

In addition, referring to FIG. 6B, the group table may include a group identifier, a group type, and an action bucket. In this case, the group identifier may match the action of the flow rule. In addition, the group type may be "ALL", "SELECT", "INDIRECT" and "FAST-FAILOVER". The action bucket may include an action corresponding to the group. In this case, the action bucket may include information about the main route and the alternate route. For example, if the group type is "FAST-FAILOVER", the action bucket may be set as "main path-output through port 3" or "alternative path-output through port 4."

In this case, the flow table and the group table may be received from the open flow controller 540 through the communication module 510.

The processor 530 may receive a packet through the communication module 510. The processor 530 may deliver the packet to another open flow switch 500 or the destination host according to the flow corresponding to the packet through the communication module 510. In this case, the processor 530 may deliver the received packet along a path based on the flow table and the group table.

Referring to FIG. 7, the first openflow switch 710 included in the openflow based network 700 according to an embodiment of the present invention may provide a packet corresponding to the received first flow to the destination host. According to the set path, it may be transmitted to the second open flow switch 720 through the link.

In addition, the second openflow switch 720 may transmit a packet received from the openflow controller 540 to the fourth openflow switch 740. The fourth openflow switch 740 may transmit a packet received from the second openflow switch 720 to the third host 172.

As such, the open flow-based network 700 may deliver the packet to the destination host according to a predetermined path of the flow.

On the other hand, if an error occurs in a specific component included in a path for delivering a packet, the processor 530 may set an alternative path for bypassing the corresponding component. In this case, the component may be another open flow switch 500 to receive a packet, or may include a link with the corresponding open flow switch 500.

The error may mean that another open flow switch through which the processor 530 delivers the packet through the communication module 510 is broken, or a problem may occur in which the packet is received by the corresponding open flow switch. Or, when the processor 530 transmits a packet through the communication module 510, the link with another open flow switch that receives the packet is broken, or a problem occurs in the link, so that the open flow switch detects the packet. It may mean that it cannot be received.

Specifically, when the packet cannot be delivered to the target open flow switch that needs to deliver the packet according to the path, the processor 530 may detect an error of a component including a target open flow switch or a link with the target open flow switch. . In this case, the error may be for a link with the open flow switch 500 or the open flow switch 500.

If an error is detected on the component, the processor 530 may set an alternate path based on information of the flow corresponding to the packet and information of the component in which the error occurs. In this case, the alternative path may be the processor 530 received the alternative path through the open flow controller 540 and stored in the memory 520.

For example, the alternate path may be stored in the group table stored in the memory 520. In this case, the group entry corresponding to the alternate path may be a group type set to "FAST-FAILOVER".

The alternate path may be generated by the OpenFlow Controller 540 based on the information of one or more flows collected based on the error. In addition, one or more flows collected based on an error may be a flow in which transmission of a packet is stopped based on the error.

Alternate routes may be generated, one per flow group with the same destination host address. For example, the open flow controller 540 may classify flows having the same address of the destination host and generate one or more flow groups. Alternatively, the open flow controller 540 may generate one or more flow groups by classifying flows having the same address of the open flow switch 500 connected to the destination host. In the following description, a flow group is generated based on a flow in which the destination host has the same address, but is not limited thereto.

The open flow controller 540 may generate one substitute path for each flow group. That is, the open flow controller 540 may generate one alternative path per one or more flows having the same destination included in the flow group.

In this case, the open flow controller 540 may classify the same flow group to the destination host based on the virtual local address network (VLAN) ID set corresponding to the open flow switch 500 and the link. In this case, the VLAN ID set corresponding to the open flow switch 500 and the link may be a unique identifier.

In addition, the open flow controller 540 may generate an alternate route based on a flow tagging mechanism. The open flow controller 540 may set a flow rule that matches the header tag included in the alternate path.

The alternate path may be set differently based on the type of component in which an error may occur. For example, if the component is an edge component that includes an open flow switch 500 or a link corresponding to the open flow switch 500 that is directly connected to the host, the alternate path is based on the link included in that edge component. Can be generated. Alternatively, when the component is a core component including an open flow switch 500 connected to another open flow switch 500 or a link corresponding to the open flow switch 500, the alternative path is an open flow included in the core component. It may be generated based on the switch 500.

Through this process, the open flow controller 540 may generate an alternative path to bypass the open flow controller 540 corresponding to the error and the open flow controller 540 located within a predetermined hop number. In this case, the predetermined hop number may be two hops.

The processor 530 may receive and store an alternative path corresponding to one or more flow groups from the open flow controller 540 through the communication module 510. In this case, the processor 530 may store the alternative path corresponding to the flow group as a group entry in the group table. In this case, the processor 530 may set the group type to "FAST-FAILOVER" and store the group entry including the corresponding alternative path in the group table.

Hereinafter, an error recovery process of the open flow switch 500 will be described with reference to FIGS. 7 and 8.

Referring to FIG. 7, the VLAN ID of the first openflow switch 710 is 1, the VLAN ID of the second openflow switch 720 is 3, and the VLAN ID of the third openflow switch 730 is 5, fourth. The VLAN ID of the open flow switch 740 may be 9, the VLAN ID of the fifth open flow switch 750 may be 7, and the VLAN ID of the sixth open flow switch 760 may be 12.

In addition, referring to FIG. 7, the error may be generated in the core component corresponding to the second openflow switch 720. That is, the error may be caused by the second open flow switch 720 or the

link

780, 781, 790 corresponding to the second open flow switch 720.

The first openflow switch 710 may transfer the received first packet to the second openflow switch 720. In this case, the first packet may be a packet in which the destination host is the third host 772.

The first openflow switch 710 transmits the first packet to the first packet based on the flow table and the group table stored in the memory 520 of the first openflow switch 710 to deliver the first packet to the third host 772. The path of the corresponding flow can be extracted. For example, the path may be set based on a group entry of the group table that matches the group identifier included in the flow rule corresponding to the first packet stored in the flow table. That is, the path may be to deliver the packet to the fourth open flow switch 740 through the second open flow switch 720.

The first openflow switch 710 may deliver the first packet to the second openflow switch 720 based on the path. In this case, if the second open flow switch 720 cannot receive the first packet due to an error, the first open flow switch 710 may detect an error of the second open flow switch 720.

The first openflow switch 710 may extract an alternate path based on the information of the second openflow switch 720 and the information of the flow corresponding to the first packet. For example, the first open flow switch 710 may extract a flow rule corresponding to the flow. The first open flow switch 710 may extract a group entry matching the flow rule of the corresponding flow. The first openflow switch 710 may extract an alternate path based on the action bucket included in the group entry.

In this case, the alternative path may be generated and delivered by the open flow controller 540 as described above. In this case, the alternate path may be extracted based on the VLAN ID of the open flow switch 500 corresponding to the error. For example, the alternate path may be extracted based on the VLAN ID of the second openflow switch 720. In addition, the alternative path may include a second open flow switch 720 and an open flow switch 500 within a predetermined hop number as described above.

The first openflow switch 710 may deliver the first packet to the first host 770 through the sixth openflow switch 760 and the third openflow switch 730 according to the alternative path.

Referring to FIG. 8, the first openflow switch 710 may transfer the received second packet to the second openflow switch 720. In this case, the second packet may be a packet in which the destination host is the third host 772.

In addition, the second openflow switch 720 may transmit the second packet to the fourth openflow switch 740. At this time, if an error occurs in the edge component corresponding to the fourth open flow switch 740, the second open flow switch 720 may include information of the fourth open flow switch 740 and information of a flow corresponding to the second packet. Based on the alternative route can be extracted.

For example, the alternate path may be generated based on a link between the failed second openflow switch 720 and the fourth openflow switch 740. The alternate path may be extracted based on the VLAN ID 10 of the link between the second openflow switch 720 and the fourth openflow switch 740. That is, the alternate path may be generated corresponding to the component having a VLAN ID of 10.

The alternate path is the second openflow switch 720 sends the second packet through the first openflow switch 710, the fifth openflow switch 750, and the fourth openflow switch 740 to the third host 772. It may be to pass on. Therefore, the second openflow switch 720 can deliver the second packet to the first openflow switch 710.

Next, an open flow controller 540 according to an embodiment of the present invention will be described with reference to FIG. 9.

9 is a block diagram of an openflow controller 540 according to an embodiment of the present invention.

The open flow controller 540 may be connected to the open flow switch 500. The open flow controller 540 may generate an alternate path based on an error corresponding to a plurality of open flow switches 500 or links included in the open flow based network 100. In this case, the open flow controller 540 may include a communication module 900, a memory 910, and a processor 920.

The communication module 900 may perform data communication with a plurality of open flow switches 500 included in the open flow based network 100.

The memory 910 stores an alternative path generation program. In this case, the memory 910 collectively refers to a nonvolatile storage device that maintains stored information even when power is not supplied, and a volatile storage device that requires power to maintain stored information.

The processor 920 may generate an alternative path in case an error occurs on the open flow switch 500 or a link between the two open flow switches 500 based on the alternative path generation program. In this case, the error may be an error for the open flow switch 500 included in the specific flow. Alternatively, the error may be an error for a link corresponding to the open flow switch 500 included in the specific flow.

In detail, the processor 920 may collect a plurality of flows of the connected open flow switch 500.

The processor 920 may classify each flow into a plurality of flow groups based on the information of the plurality of flows.

In this case, the processor 920 may classify a plurality of flows based on VLAN IDs corresponding to components such as an open flow switch 500 and a link included in each flow.

The processor 920 may generate an alternate path corresponding to each flow group.

In this case, when the component corresponding to the error is an edge component, the processor 920 may generate an alternative path based on a link included in the component corresponding to the error. In this case, the edge component may be a link corresponding to the open flow switch 500 directly connected to the host or the open flow switch 500 directly connected to the host.

In addition, when the component corresponding to the error is a core component, the processor 920 may generate an alternative path based on the open flow switch 500 included in the component. In this case, the core component may be a link corresponding to the open flow switch 500 connected to the other open flow switch 500 or the open flow switch 500 connected to the other open flow switch 500.

In addition, the processor 920 may transfer the alternate paths to the plurality of open flow switches 500 through the communication module 900.

Next, the error recovery method of the openflow switch 500 according to an embodiment of the present invention will be described with reference to FIG. 10.

10 is a flowchart of an error recovery method in the openflow switch 500 according to an embodiment of the present invention.

The open flow switch 500 detects an error on a component included in a path corresponding to the flow (S1000). At this time, the component includes an open flow switch 500 or a link. In addition, the component corresponding to the error is a link with the open flow switch 500 for delivering packets according to the flow or the open flow switch 500 for delivering packets according to the flow.

In addition, the open flow switch 500 sets an alternative path corresponding to the flow based on the information of the flow and the information of the component corresponding to the error (S1010).

In this case, before detecting an error, the open flow switch 500 may store a flow table including one or more flow rules and a group table including one or more group entries.

The open flow switch 500 may extract a flow rule corresponding to the flow stored in the flow table. The open flow switch 500 may select a group entry that matches the extracted flow rule. Thereafter, the openflow switch 500 may set an alternate path based on the selected group entry.

Next, an error recovery method of the open flow controller 540 according to an embodiment of the present invention will be described with reference to FIG. 11.

11 is a flowchart illustrating an error recovery method of the open flow controller 540 according to an embodiment of the present invention.

The open flow controller 540 collects a plurality of flows (S1100).

The open flow controller 540 classifies each flow into a flow group based on the collected information of the plurality of flows (S1110).

The open flow controller 540 generates an alternative path corresponding to the flow group (S1120). At this time, the alternate path corresponds to an error of the flow. In addition, the error is an error for the open flow switch 500 included in the flow, or an error for a link corresponding to the open flow switch 500 included in the flow.

The open flow controller 540 transfers alternate paths generated by the plurality of open flow switches 500 (S1130).

In the open flow switch 500, the open flow controller 540, and the error recovery method for error recovery according to an embodiment of the present invention, each open flow switch 500 replaces a plurality of flows on an open flow-based network. Instead of saving a route, you can store alternate routes for flow groups with the same address at the destination. Therefore, the open flow switch 500, the open flow controller 540, and the error recovery method for error recovery can reduce the number of alternative paths stored in each open flow switch 500, and thus are efficient.

In addition, the open flow switch 500, the open flow controller 540, and the error recovery method for error recovery may reduce an overload of the open flow controller 540. Therefore, the open flow switch 500, the open flow controller 540, and the error recovery method for error recovery can quickly cope with errors that may occur in an open flow-based network.

One embodiment of the present invention can also be implemented in the form of a recording medium containing instructions executable by a computer, such as a program module executed by the computer. Computer readable media can be any available media that can be accessed by a computer and includes both volatile and nonvolatile media, removable and non-removable media. In addition, the computer readable medium may include a computer storage medium. Computer storage media includes both volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data.

Although the methods and systems of the present invention have been described in connection with specific embodiments, some or all of their components or operations may be implemented using a computer system having a general purpose hardware architecture.

The foregoing description of the present invention is intended for illustration, and it will be understood by those skilled in the art that the present invention may be easily modified in other specific forms without changing the technical spirit or essential features of the present invention. will be. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive. For example, each component described as a single type may be implemented in a distributed manner, and similarly, components described as distributed may be implemented in a combined form.

The scope of the present invention is shown by the following claims rather than the above description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included in the scope of the present invention. do.

Claims

In the openflow switch to recover from the error,

Communication module,

The memory where the error recovery program is stored, and

Including a processor for executing the program,

When an error is detected on a component included in a path corresponding to the flow, the processor determines an alternative path corresponding to the flow based on information of the flow and information of a component corresponding to the error, according to execution of the program. Set it up,

The component includes an openflow switch or link,

The component corresponding to the error is an openflow switch in which the processor forwards the packet according to the flow or an error in a link corresponding to an openflow switch that forwards the packet according to the flow.
The method of claim 1,

The memory stores a flow table including one or more flow rules and a group table including one or more group entries,

The processor extracts a flow rule corresponding to the flow stored in the flow table, selects a group entry matching the extracted flow rule, and sets an alternative path corresponding to the flow based on the selected group entry. That, open flow switch.
The method of claim 2,

The flow rule includes an address of a source host, an address of a destination host, an identifier and action of a virtual local area network (VLAN),

And the group entry comprises a group type and an action bucket.
The method of claim 1,

And the processor receives a path corresponding to the flow and an alternative path corresponding to the flow from an openflow controller.
The method of claim 4, wherein

The alternative path is generated by the open flow controller to classify the plurality of flows into one or more flow groups based on the information of the plurality of flows collected based on the error, and to correspond to each of the flow groups. Flow switch.
The method of claim 4, wherein

The alternative path is generated based on a link included in a component corresponding to the error when the component corresponding to the error is an edge component, and corresponds to the error when the component corresponding to the error is a core component. Generated based on the OpenFlow switches included in the component,

The core component is a link corresponding to an open flow switch connected to another open flow switch or an open flow switch connected to the other open flow switch,

The edge component is an openflow switch connected to a host or a link corresponding to an openflow switch connected to the host.
The method of claim 1,

The alternate path is generated to include a component corresponding to the error and a component located within a predetermined hop number.
In the open flow controller,

Communication module for performing data communication with a plurality of open flow switch,

The memory where the alternate path generator is stored and

Including a processor for executing a program stored in the memory,

The processor collects a plurality of flows according to the execution of the program, classifies each flow into a flow group based on the information of the plurality of flows, generates an alternative path corresponding to the flow group, and opens the plurality of opens. Passing the generated alternate path to a flow switch,

The alternate path corresponds to an error in the flow,

The error is an error for at least one of the one or more components included in the flow,

And said component comprises an openflow switch or link.
The method of claim 8,

The processor classifies the plurality of flows based on a virtual local address network (VLAN) identifier corresponding to a component included in each flow,

And said component comprises an openflow switch or link.
The method of claim 8,

If the component corresponding to the error is an edge component, the processor generates the replacement path based on a link included in the component corresponding to the error,

When the component corresponding to the error is a core component, the replacement path is generated based on the open flow switch included in the component corresponding to the error.

The core component is a link corresponding to an open flow switch connected to another open flow switch or an open flow switch connected to the other open flow switch,

The edge component is a link corresponding to an openflow switch connected to a host or an openflow switch connected to the host among the plurality of openflow switches.
In the error recovery method in the openflow switch,

Detecting an error on a component included in a path corresponding to the flow; And

Setting an alternative path corresponding to the flow based on information of the flow and information of a component corresponding to the error,

The component includes an openflow switch or link,

And wherein the component corresponding to the error is an open flow switch for delivering a packet in accordance with the flow or an error in a link corresponding to an openflow switch for delivering a packet in accordance with the flow.
The method of claim 11,

Prior to the step of detecting the error, further comprising storing a flow table including one or more flow rules and a group table including one or more group entries,

Setting the alternate path,

Extracting a flow rule corresponding to the flow stored in the flow table;

Selecting a group entry that matches the extracted flow rule; And

Establishing the alternate path based on the selected group entry.
In the error recovery method in the OpenFlow controller,

Collecting a plurality of flows and classifying each flow into a flow group based on the information of the plurality of flows;

Creating an alternate route corresponding to the flow group; And

Delivering the generated alternate paths to the plurality of openflow switches;

The alternate path corresponds to an error in the flow,

The error is an error for at least one of the one or more components included in the flow,

And the component comprises an openflow switch or link.
The method of claim 13,

Generating an alternative route corresponding to the flow group,

If the component corresponding to the error is an edge component, generating the substitute path based on a link included in the component corresponding to the error; And

If the component corresponding to the error is a core component, generating the substitute path based on an openflow switch included in the component corresponding to the error,

The core component is a link corresponding to an open flow switch connected to another open flow switch or an open flow switch connected to the other open flow switch,

And the edge component is a link corresponding to an openflow switch connected to a host or an openflow switch connected to the host among the plurality of openflow switches.
A computer-readable recording medium having recorded thereon a program for performing the method according to any one of claims 11 to 14 on a computer.