WO2014173235A1

WO2014173235A1 - Forwarding path generating method, controller, and system

Info

Publication number: WO2014173235A1
Application number: PCT/CN2014/075149
Authority: WO
Inventors: 李泉材; 田应军; 王文健
Original assignee: 华为技术有限公司
Priority date: 2013-04-22
Filing date: 2014-04-11
Publication date: 2014-10-30
Also published as: CN104113474A; CN104113474B

Abstract

The present invention belongs to the technical field of networks, and disclosed are a forwarding path generating method, controller, and system. The method comprises: obtaining network information of a first host by using a received first ARP request; obtaining network information of a second host by constructing a second ARP request; deciding to generate a forwarding path according to the network information of the first host and the second host; and delivering a forwarding flow table to each switch on the forwarding path, so that each switch on the forwarding path forwards a data packet between the first host and the second host according to the forwarding flow table. According to the present invention, a controller is used to replace a part of OpenFlow switches that implement a gateway/router in an OpenFlow network, so that the problem that a dedicated OpenFlow switch in the OpenFlow network cannot implement the function is solved, and the effect that a switch functioning as a gateway/router does not need to be set separately in the OpenFlow network is achieved.

Description

Method, controller and system for generating forwarding path The present application claims to be filed on April 22, 2013 by the Chinese Patent Office, the application number is 201310140475.6, and the invention name is "transmission path generation method, controller and system" The entire contents of the above-identified patent application are incorporated herein by reference.

Technical field

The present invention relates to the field of network technologies, and in particular, to a method, a controller, and a system for generating a forwarding path.

Background technique

OpenFlow is a new type of network switching model, including OpenFlow switch (OpenFlow Switch) and controller (Crontroller); Among them, OpenFlow switch forwards the data layer; controller controls the network centrally to realize the function of the control layer. OpenFlow switches fall into two categories: dedicated OpenFlow switches and switches that support OpenFlow. A dedicated OpenFlow switch does not have control logic. It is only a simple path component for forwarding data packets between ports. The received data packets are forwarded according to OpenFlow mode. The switches supporting OpenFlow can forward data according to OpenFlow mode. Packets can also be forwarded according to the forwarding mode of the existing switch.

In the actual OpenFlow network, the OpenFlow switch and the controller jointly complete the packet forwarding process controlled by the switch/router in the existing network, thereby realizing the separation of data forwarding and routing control. Please refer to FIG. 1 , which illustrates an implementation environment of an existing openflow network, where the implementation environment includes a controller 120, a first host 140 and a second host 142, a first switch 160, a second switch 162, and a third switch 164. The fourth switch 166 and the fifth switch 168, wherein the first host 140 and the second host 142 belong to different subnets, respectively connected to ports of the first switch 160 and the second switch 162, and the fourth switch 166 and the fifth switch 168, respectively, implements the configuration gateway function of the first host 140 and the second host 142, that is, the first host 140 configures the first gateway, the second host 142 configures the second gateway, and the functions of the first gateway and the second gateway are respectively performed by the fourth switch 166 and fifth switch 168 are implemented. During the actual communication between the first host 140 and the second host 142, the first host 140 first obtains the MAC of the first gateway through an ARP (Address Resolution Protocol) learning process between the first host 140 and the fourth switch 166 (Medium/ Media Access Control, medium access control layer) address, after obtaining the MAC address of the first gateway, the first host sends a data packet of the destination host to the second host 142 to the fourth switch 166, and after receiving the data packet, the fourth switch receives the data packet. If the forwarding flow table information corresponding to the data packet is not queried, the data packet is reported to the controller, and the controller sends the forwarding flow table according to the subnet information and the destination IP address of the data packet, and the fourth The switch 166 forwards the data packet to the fifth switch 168. The fifth switch 168 and the second host 142 obtain the MAC address of the second host 142 through the ARP learning process, and obtain the MAC address of the second host 142. The data packet is forwarded to the second host 142.

In the process of implementing the present invention, the inventors have found that the prior art has at least the following disadvantages: Some OpenFlow switches need to undertake gateway/routing functions, such as the fourth switch 166 and the fifth switch 168 in FIG. 1, but in the OpenFlow network. This function cannot be implemented by a dedicated OpenFlow switch, that is, if the fourth switch 166 and the fifth switch 168 acting as gateways are dedicated Openflow switches, this function cannot be implemented.

Summary of the invention

In order to solve the problem that the dedicated OpenFlow switch in the OpenFlow network cannot implement the function of the gateway/route, the embodiment of the present invention provides a method, a controller, and a system for generating a forwarding path. The technical solution is as follows:

According to an aspect of the present invention, an embodiment of the present invention provides a method for generating a forwarding path, where the method includes:

The controller obtains the network information of the first host by using the received first ARP request, where the first ARP request is sent by the first host, and the switch connected to the first host cannot find the forwarding flow table. An ARP request forwarded to the controller;

The controller acquires network information of the second host by constructing a second ARP request;

The controller generates a forwarding path between the first host and the second host according to the network information of the first host and the network information of the second host; Transmitting, by the controller, a forwarding flow table to each switch on the forwarding path, so that each switch on the forwarding path is between the first host and the second host according to the forwarding flow table Forward the packet.

In a first possible implementation manner of the first aspect, if the destination IP address in the first ARP request is an IP address of the first gateway, and the first gateway is a configuration gateway of the first host, After the receiving, by the received first ARP request, the network information of the first host, the controller further includes: the controller feeding back a first ARP response to the first host by using a switch connected to the first host, where The source MAC address and the source IP address in the first ARP response are respectively the MAC address and the IP address of the first gateway.

With reference to the first possible implementation manner of the first aspect, in a second possible implementation, the controller acquires network information of the second host by constructing the second ARP request, including:

Receiving, by the controller, a data packet sent by the first host, where a destination MAC address of the data packet is a MAC address of the first gateway, and a destination IP address is an IP address of the second host; Constructing a second ARP request according to the IP address of the second host, where the source MAC address and the source IP address of the second ARP request are respectively a MAC address and an IP address of the second gateway, and the destination IP address is the second host IP address, the second gateway is a configuration gateway of the second host;

The controller sends the second ARP request to all hosts in the subnet where the second host is located by using a switch in a subnet where the second host is located;

Receiving, by the switch connected to the second host, the second ARP response that is sent by the second host, where the source MAC address and the source IP address of the second ARP response are respectively the MAC address of the second host Address and IP address.

With reference to the second possible implementation manner of the first aspect, in a third possible implementation manner, before the acquiring, by the controller, the network information of the first host by using the received first ARP request, the controller further includes:

The controller pre-stores a gateway, a network number, and a subnet mask of a subnet where the first host and the second host are located, and a MAC address and an IP address of the first gateway and the second gateway; The controller sends the second ARP request by using a switch of a subnet where the second host is located All hosts in the subnet where the second host is located, including;

The controller sends the second ARP request to all hosts in the subnet where the second host is located according to the gateway, the network number, and the subnet mask of the subnet where the second host is located.

With reference to the first aspect, in a fourth possible implementation, if the destination IP address in the first ARP request is an IP address of the second host, the acquiring the first ARP request by using the received After a host's network information, it also includes:

The controller feeds back a first ARP response to the first host by using a switch connected to the first host, where a source MAC address in the first ARP response is a MAC address of the first proxy device, and a source IP address is The IP address of the second host, so that the first host uses the MAC address of the first proxy device as the MAC address of the second host, where the first proxy device is located corresponding to the first host A proxy device within a subnet.

With reference to the fourth possible implementation manner of the first aspect, in a fifth possible implementation manner, the controller, by configuring the second ARP request, to obtain the network information of the second host, includes:

Receiving, by the controller, a data packet sent by the first host, where a destination MAC address of the data packet is a MAC address of the first proxy device, and a destination IP address is an IP address of the second host; The device generates a second ARP request according to the IP address of the second host, where the source MAC address of the second ARP request is the MAC address of the second proxy device, and the source IP address is the IP address of the first host, and the destination IP address. The address is the IP address of the second host, so that the second host uses the MAC address of the second proxy device as the MAC address of the first host, and the second proxy device corresponds to the second The proxy device in the subnet where the host is located;

Receiving, by the switch connected to the second host, the second ARP response that is sent by the second host, where the source MAC address and the source IP address of the second ARP response are respectively the MAC address of the second host Address IP address.

With reference to the fifth possible implementation manner of the first aspect, in a sixth possible implementation, before the acquiring, by the first ARP request, the network information of the first host, the controller further includes: The controller pre-stores a gateway, a network number, and a subnet mask of a subnet where the first host and the second host are located, and a MAC address of the first proxy device and the second proxy device; The controller sends the second ARP request to all hosts in the subnet where the second host is located by using a switch of the subnet where the second host is located, including:

With reference to the first aspect, the first, second, third, fourth, fifth or sixth possible implementation manner of the first aspect, in a seventh possible implementation manner, the The network information of the first host and the network information of the second host determine a forwarding path between the first host and the second host, including:

Calculating a shortest forwarding path between the first host and the second host according to network information of the first host and network information of the second host; using the shortest forwarding path as the first host and a forwarding path between the second hosts;

Or

Calculating an optimal forwarding path between the first host and the second host according to network information of the first host and network information of the second host; using the optimal forwarding path as the first A forwarding path between the host and the second host.

In a second aspect, a controller is provided for use in an OpenFlow network including at least one switch, where the controller includes:

a first information acquiring module, configured to acquire network information of the first host by using the received first ARP request, where the first ARP request is a switch sent by the first host and connected to the first host The ARP request forwarded to the controller after forwarding the flow table cannot be found;

a second information acquiring module, configured to acquire network information of the second host by constructing a second ARP request;

a path generating module, configured to generate the first host and the network according to the network information of the first host acquired by the first information acquiring module and the network information of the second host acquired by the second information acquiring module a forwarding path between the second hosts;

a flow table issuing module, configured to perform each exchange on a forwarding path generated by the path generation module The forwarding flow table is sent by the machine, so that each switch on the forwarding path forwards the data packet between the first host and the second host according to the forwarding flow table.

In a first possible implementation manner of the second aspect, if the destination IP address in the first ARP request is an IP address of the first gateway, the first gateway is a configuration gateway of the first host, where The controller also includes:

a first feedback module, configured to feed back, by the switch connected to the first host, the first ARP response to the first host, where the source MAC address and the source IP address in the first ARP response are respectively the first The MAC address and IP address of the gateway.

With reference to the first possible implementation manner of the second aspect, in the second possible implementation, the second information acquiring module includes:

a first receiving unit, configured to receive a data packet sent by the first host, where a destination MAC address of the data packet is a MAC address of the first gateway, and a destination IP address is an IP address of the second host;

a first constructing unit, configured to construct a second ARP request according to the IP address of the second host in the data packet received by the first receiving unit, where the source MAC address and the source IP address of the second ARP request are respectively The MAC address and the IP address of the second gateway, the destination IP address is the IP address of the second host, and the second gateway is the configuration gateway of the second host;

a first sending unit, configured to send, by using a switch in a subnet where the second host is located, a second ARP request configured by the first configuration unit to all hosts in a subnet where the second host is located; a unit, configured to receive, by using a switch that is connected to the second host, a second ARP response that is sent by the second host, where the source MAC address and the source IP address of the second ARP response are respectively the MAC address of the second host Address and IP address.

With reference to the second possible implementation of the second aspect, in a third possible implementation, the controller further includes:

a first pre-storage module, configured to pre-store a gateway, a network number, and a subnet mask of a subnet where the first host and the second host are located, and a MAC address of the first gateway and the second gateway IP address;

The first sending unit is specifically configured to be pre-stored according to the first pre-storage module The gateway, the network number, and the subnet mask of the subnet where the second host is located sends the second ARP request to all hosts in the subnet where the second host is located.

With reference to the second aspect, in a fourth possible implementation, if the destination IP address in the first ARP request is the IP address of the second host, the controller further includes:

a second feedback module, configured to feed back, by the switch connected to the first host, a first ARP response to the first host, where a source MAC address in the first ARP response is a MAC address of the first proxy device, and a source The IP address is the IP address of the second host, so that the first host uses the MAC address of the first proxy device as the MAC address of the second host, and the first proxy device corresponds to the first A proxy device in a subnet where the host resides.

With reference to the fourth possible implementation of the second aspect, in a fifth possible implementation, the second information acquiring module includes:

a third receiving unit, configured to receive a data packet sent by the first host, where a destination MAC address of the data packet is a MAC address of the first proxy device, and a destination IP address is an IP address of the second host;

a second constructing unit, configured to construct a second ARP request according to the IP address of the second host in the data packet received by the third receiving unit, where the source MAC address of the second ARP request is the MAC address of the second proxy device An address, a source IP address is an IP address of the first host, and a destination IP address is an IP address of the second host, so that the second host uses the MAC address of the second proxy device as the first host MAC address, the second proxy device is a proxy device corresponding to a subnet in which the second host is located;

a second sending unit, configured to send, by using a switch in a subnet where the second host is located, a second ARP request configured by the second configuration unit to all hosts in a subnet where the second host is located; a unit, configured to receive, by using a switch that is connected to the second host, a second ARP response that is sent by the second host, where the source MAC address and the source IP address of the second ARP response are respectively the MAC address of the second host Address IP address.

With reference to the fifth possible implementation of the second aspect, in a sixth possible implementation, the controller further includes:

a second pre-storage module, configured to pre-store the first host and the second host a gateway, a network number, and a subnet mask of the network, and a MAC address of the first proxy device and the second proxy device;

The second sending unit is configured to send the second ARP request to the second host according to a gateway, a network number, and a subnet mask of a subnet where the second host is pre-stored by the second pre-storage module. All hosts in the subnet.

With reference to the second aspect, the first, second, third, fourth, fifth or sixth possible implementation manner of the second aspect, in a seventh possible implementation manner, the path Generate modules, including:

a shortest generating unit, configured to calculate, according to the network information of the first host acquired by the first information acquiring module and the network information of the second host acquired by the second information acquiring module, the first host and the first a shortest forwarding path between the two hosts; using the shortest forwarding path as a forwarding path between the first host and the second host;

Or

An optimal generating unit, configured to calculate the first host and the network according to the network information of the first host acquired by the first information acquiring module and the network information of the second host acquired by the second information acquiring module An optimal forwarding path between the second host; the optimal forwarding path is used as a forwarding path between the first host and the second host.

In a third aspect, a forwarding path generation system is provided, comprising the controller, the first host and the second host of any of the second aspect and the various possible implementations of the second aspect.

The beneficial effects brought by the technical solutions provided by the embodiments of the present invention are:

The controller replaces part of the OpenFlow switch that implements the gateway/routing function in the OpenFlow network, thereby solving the problem that the dedicated OpenFlow switch in the OpenFlow network cannot implement the function, and the OpenFlow network does not need to be separately set to function as a gateway/ The effect of the routing function of the switch.

DRAWINGS

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the prior art description will be briefly described below, obviously, the following The drawings in the description are only some of the embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without any inventive labor.

1 is a schematic diagram of an implementation environment of an embodiment of the present invention;

2 is a flowchart of a method for generating a forwarding path according to Embodiment 1 of the present invention; FIG. 3 is a flowchart of a method for generating a forwarding path according to Embodiment 2 of the present invention; FIG. 4 is a flowchart of Embodiment 2 of the present invention; Environmental diagram

5 is a flowchart of a method for generating a forwarding path according to Embodiment 3 of the present invention; FIG. 6 is a schematic diagram of an implementation environment of Embodiment 3 of the present invention;

7 is a schematic structural diagram of a controller according to Embodiment 4 of the present invention;

8 is a schematic structural diagram of a controller according to Embodiment 5 of the present invention;

9 is a schematic structural diagram of a controller according to Embodiment 6 of the present invention;

Figure 10 is a block diagram showing the structure of a system for generating a forwarding path according to a seventh embodiment of the present invention; Figure 11 is a block diagram showing the structure of a controller according to Embodiment 8 of the present invention;

Figure 12 is a block diagram showing the structure of a controller provided in Embodiments 9 and 10 of the present invention.

detailed description

The embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

Embodiment 1

Referring to FIG. 2, a flowchart of a method for generating a forwarding path according to Embodiment 1 of the present invention is shown. In this embodiment, the method for generating the forwarding path is applied to the controller as an example for illustration. The method for generating the forwarding path includes:

Step 201: The controller acquires network information of the first host by using the received first ARP request. The controller acquires network information of the first host by using the received first ARP request, where the first

The ARP request is sent by the first host, and the switch connected to the first host cannot find the ARP request forwarded to the controller after forwarding the flow table.

Step 202: The controller acquires network information of the second host by constructing a second ARP request. To generate a forwarding path between the first host and the second host, the controller constructs the second

The ARP requests to obtain the network information of the second host. Step 203: The controller generates a forwarding path between the first host and the second host according to the network information of the first host and the network information of the second host.

The controller generates a forwarding path according to the network information of the first host and the network information of the second host, so that the first host and the second host communicate according to the forwarding path.

Step 204: The controller sends a forwarding flow table to each switch on the forwarding path.

The controller generates a corresponding forwarding flow table for the switch on the forwarding path according to the generated forwarding path, and sends the generated forwarding flow table to the corresponding switch, so that the corresponding switch updates the local forwarding flow table according to the forwarding flow table, and according to The updated forwarding flow table forwards the communication data packet between the first host and the second host.

In summary, in the method for generating a forwarding path provided by the embodiment, the controller obtains the network information of the first host and the second host, and generates a forwarding path according to the obtained network information of the first host and the second host. In order to communicate between the first host and the second host, the problem that the dedicated OpenFlow switch in the OpenFlow network cannot implement the function is solved, and the effect that the switch functioning as the gateway/routing function is not required in the OpenFlow network is achieved.

It should be noted that the specific implementation environment may be divided into two situations. In the first case, when the first host and the second host respectively configure the first gateway and the second gateway, the controller implements the functions of the first gateway and the second gateway. In the second case, when the first host and the second host do not have a default gateway configured, the controller implements the functions of the first proxy device and the second proxy device. First, the first case will be described in detail;

Embodiment 2

Please refer to FIG. 3, which is a flowchart of a method for generating a forwarding path according to Embodiment 2 of the present invention. This embodiment is mainly illustrated by applying the forwarding path generation method to the implementation environment shown in FIG. 4. Referring to FIG. 4, the implementation environment includes a controller 420, a first host 440, a second host 442, a third host 444, and a fourth host 446, a first switch 460, a second switch 462, a third switch 464, and a fourth The switch 466 and the fifth switch 468, wherein the first host 440 belongs to the first subnet, the second host 442, the third host 444, and the fourth host 446 belong to the second subnet, and the first host 440 and the third host 444 are connected to On the port of the first switch 460, the first The second host 442 is connected to the port of the second switch 462, and the fourth host 446 is connected to the port of the fifth switch 468. It is assumed that the first host 440 is configured as the first gateway, and the second host 442 is configured as the second gateway. The gateway, the first host 440 belongs to the first subnet, the second host 442, the third host 444, and the fourth host 446 belong to the second subnet, and the first gateway and the second gateway are implemented by the controller 420. The method includes:

Step 301: Pre-store a gateway, a network number, and a subnet mask of a subnet where the first host and the second host are located, and a MAC address and an IP address of the first gateway and the second gateway.

The controller pre-stores the gateway, the network number and the subnet mask of the subnet where the first host 440 and the second host 442 are located, and the MAC address and IP address of the first gateway and the second gateway, so that the controller 420 is in the subsequent process. Implementing a first gateway corresponding to the first host 440 and a second gateway corresponding to the second host 442 to obtain MAC address, IP address, and port information of the first host 440 and the second host 442; and simultaneously according to the gateway of the subnet , network number and subnet mask decision forwarding path.

Step 302: The first host sends a first ARP request to the first switch.

The first host 440 needs to communicate with the outside world. First, the MAC address of the first gateway is queried according to the configured gateway, that is, the IP address of the first gateway. Therefore, the first host 440 constructs a first ARP request, and the source MAC address of the first ARP request. The address is the MAC address of the first host 440, the source IP address is the IP address of the first host 440, the destination MAC address is 0, and the destination IP address is the IP address of the first gateway. The first host 440 sends the first ARP request to the first switch 460.

Correspondingly, the first switch 460 receives the first ARP request.

Step 303: The first switch queries the local forwarding flow table. If the forwarding flow table information corresponding to the received first ARP request is not found, the first switch sends the information to the controller in the form of a packet input message (Packet-ln).

The first switch 460 queries the local forwarding flow table according to the destination IP address in the received first ARP request, and if the forwarding flow table information corresponding to the destination IP address is queried, the forwarding is performed according to the forwarding flow table information; To the forwarding flow table information corresponding to the destination IP address, the received first ARP request is sent to the controller 420 in the form of a packet input message.

Correspondingly, the controller 420 receives the first ARP request.

Step 304: The controller acquires network information of the first host by using the received first ARP request. The controller 420 obtains the MAC address and the IP address of the first host 440 according to the received first ARP request, and uses the MAC address and the IP address of the first host 440 as the network information of the first host 440; due to the first ARP request The controller 420 can also obtain the port information of the first host 440 according to the need, and the MAC address, the IP address, and the port information of the first host 440 are used as the first host 440. Network information. In other words, the network information of the first host 440 may include the MAC address and IP address of the first host 440, and may also include the MAC address, IP address, and port information of the first host 440.

Step 305: The controller constructs a first ARP response, and feeds back the first ARP response to the first host by using a switch connected to the first host.

Since the controller 420 implements the function of the first gateway, when the first ARP request is received and the destination IP address is found to be the IP address of the first gateway, the controller 420 actively constructs a first ARP response, the first ARP response. The source MAC address is the MAC address of the first gateway, the source IP address is the IP address of the first gateway, the destination MAC address is the MAC address of the first host 440, and the destination IP address is the IP address of the first host 440, and the packet is The output message (Packet-Out) is sent in the form of a first ARP response from the first switch 460 to the port of the first host 440.

Correspondingly, the first host 440 receives the first ARP response.

Step 306: The first host saves a MAC address of the first gateway.

After receiving the first ARP response, the first host 440 saves the MAC address of the first gateway in the first ARP response.

After the above steps 302 to 306, the first host 440 completes the ARP learning process between the first gateway implemented by the controller 420.

Step 307: The first host sends a data packet whose destination host is the second host to the first switch. The first host 440 has obtained the MAC address of the first gateway by using the step 302 to the step 305, so the first host 440 goes to the second host. When the host 442 sends a data packet, the destination MAC address in the data packet is the MAC address of the first gateway, the destination IP address is the IP address of the second host 442, and the first host 440 sends the data packet to the first switch 460.

Correspondingly, the first switch 460 receives the data packet.

Step 308, the first switch queries the local forwarding flow table, and if the query does not correspond to the data packet, The forwarding flow table information is sent to the controller in the form of a packet input message;

The first switch 460 receives the data packet sent by the first host 440, and queries the local forwarding flow table according to the IP address in the data packet. If the forwarding flow table information corresponding to the destination IP address is queried, the information is forwarded according to the forwarding flow table information. Forwarding; if the forwarding flow table information corresponding to the destination IP address is not found, the data packet is sent to the controller 420 in the form of a packet input message.

Correspondingly, the controller 420 receives the data packet.

Step 309: The controller constructs a second ARP request according to the IP address of the second host, and sends the second ARP request to all hosts in the subnet where the second host is located through the switch in the subnet where the second host is located.

When the controller 420 receives the data packet, it does not know the MAC address of the second host 442. Since the controller 420 implements the role of the second gateway, the data of the IP address of the second host 442 is received at the destination IP address. When the packet is configured, the second ARP request is actively constructed. The source MAC address and the source IP address of the second ARP request are respectively the MAC address and the IP address of the second gateway, the destination MAC address is all zero, and the destination IP address is the IP address of the second host. And sending the second ARP request in the form of a packet output message to all hosts in the subnet where the second host 442 is located according to the gateway, the network number, and the subnet mask of the subnet where the second host 442 is located.

Correspondingly, all hosts in the subnet where the second host 442 is located receive the second ARP request, such as the second host 442, the third host 444, and the fourth host 446, where the third host 444 and the fourth host 446 are not in the Marked in Figure 3.

Step 310: The second host responds to the second ARP request.

The second host 442 receives the second ARP request sent by the second switch 462, and finds that the destination IP address in the second ARP request is the same as its own IP address, and then constructs a second ARP response, the source MAC address of the second ARP response. The address and the source IP address are respectively the MAC address and the IP address of the second host 442, and the destination MAC address and the destination IP address are respectively the MAC address IP address of the second gateway, and the second switch 462 sends the second to the controller 420. ARP response.

Correspondingly, the controller 420 receives the second ARP response fed back by the second host 442 through the switch 462 connected to the second host.

Step 31: The controller acquires network information of the second host. The controller 420 obtains the MAC address and the IP address of the second host 442 according to the received second ARP response, and uses the MAC address and the IP address of the second host 442 as the network information of the second host 442; due to the first ARP request The controller 420 can also obtain the port information of the second host 442 as needed, and use the MAC address, the IP address, and the port information of the second host 442 as the second host 442. Network information. In other words, the network information of the second host 442 may include the MAC address and IP address of the second host 442, and may also include the MAC address, IP address, and port information of the second host 442.

After the foregoing step 307 to step 31 1, the controller completes the ARP learning process between the implemented second gateway and the second host 442;

Step 312: The controller calculates a shortest forwarding path between the first host and the second host according to the network information of the first host and the network information of the second host. The shortest forwarding path is used as forwarding between the first host and the second host. Path

The controller 420 analyzes the destination IP address of the data packet sent by the first switch 460, and finds that the destination host of the data packet, that is, the second host 442 and the first host 440 are in different subnets, and determines that it is a three-layer forwarding, and The network information of the first host 440 and the second host 442 is obtained through the ARP learning process, and the forwarding path is generated according to the routing algorithm. If the forwarding path is generated according to the shortest path policy, the generated forwarding path may be: <-> Third switch 464 <-> Second switch 462. For example, when the network information of the first host 440 and the second host 442 includes the MAC address, the IP address, and the port information, the controller 420 can determine that the IP address of the first host 440 and the second host 442 is three-layer forwarding. The forwarding path is generated according to the routing algorithm decision. If the forwarding path is generated according to the shortest path policy, the forwarding path generated according to the port information of the first host 440 and the second host 442 may be: the first switch 460<->the third switch 464 <-> second switch 462.

It should be noted that the controller 420 may further calculate an optimal forwarding path between the first host 440 and the second host 442 according to the network information of the first host 440 and the network information of the second host 442. The optimal forwarding path is a chain. The optimal path of the path is used as the forwarding path between the first host 440 and the second host 442. The shortest path policy is used as an example for description.

Step 313: The controller generates a corresponding switch for the switch on the forwarding path according to the generated forwarding path. Forwarding the flow table, and sending the generated forwarding flow table to the corresponding switch;

The controller 420 generates a corresponding forwarding flow table for the switch on the forwarding path according to the generated forwarding path, and sends the generated forwarding flow table to the corresponding switch. For example, the controller 420 is the first switch 460 on the shortest path. The third switch 464 and the second switch 462 generate a corresponding forwarding flow table, and send the forwarding flow table corresponding to the first switch 460 to the first switch 460, and send the forwarding flow table corresponding to the third switch 464 to the third switch. 464. Send the forwarding flow table corresponding to the second switch 462 to the second switch 462. The third switch 464 is not labeled in Figure 3.

Step 314: The corresponding switch updates the local forwarding flow table according to the forwarding flow table.

For example, the first switch 460, the third switch 464, and the second switch 462 on the corresponding shortest path update the local forwarding flow table.

Step 315: The corresponding switch forwards the communication data packet between the first host and the second host according to the updated forwarding flow table.

For example, the first switch 460, the third switch 464, and the second switch 462 on the corresponding shortest path forward the communication data packet between the first host 440 and the second host 442 according to the updated forwarding flow table.

In summary, the method for generating a forwarding path provided by this embodiment replaces a part of an OpenFlow switch that implements a gateway/routing function in an OpenFlow network by using a controller, and the ARP function of the first gateway and the second gateway is implemented by the controller. Therefore, all the switches in the Open Flow network can implement the simple forwarding function, thereby solving the problem that the dedicated OpenFlow switch in the OpenFlow network cannot implement the gateway/routing function, and the OpenFlow network does not need to be separately set up. The effect of the gateway/route function switch. The second case will be described in detail below;

Embodiment 3

Please refer to FIG. 5, which is a flowchart of a method for generating a forwarding path according to Embodiment 3 of the present invention. This embodiment is mainly illustrated by applying the method for generating the forwarding path to the implementation environment shown in FIG. 6. Referring to FIG. 6, the implementation environment includes a controller 620, a first host 640, The second host 642, the third host 644 and the fourth host 646, the first switch 660, the second switch 662, the third switch 664, the fourth switch 666, and the fifth switch 668, wherein the first host 640 belongs to the first subnet The second host 642, the third host 644, and the fourth host 646 belong to the second subnet. The first host 640 and the third host 644 are connected to the port of the first switch 660, and the second host 642 is connected to the second switch 662. On the port, the fourth host 646 is connected to the port of the fifth switch 668. It is assumed that the first host 640 and the second host 642 are not configured with a default gateway. The first host 640 belongs to the first subnet, and the second host 642 and the third host. The host 644 and the fourth host 646 belong to the second subnet, and the information about the subnet where the first host 640 and the second host 642 are located (including the gateway, the network number, and the subnet mask) are pre-stored on the controller 620 and respectively correspond to The first proxy device and the second proxy device of the two subnets. The method includes:

Step 501: The memory pre-stores a gateway, a network number, and a subnet mask of the subnet where the first host and the second host are located, and a MAC address of the first proxy device and the second proxy device.

The controller 620 pre-stores the gateway, the network number and the subnet mask of the subnet where the first host 640 and the second host 642 are located, and the MAC addresses of the first proxy device and the second proxy device; so that the controller 620 is in the subsequent process. The first proxy device corresponding to the subnet where the first host 640 is located and the second proxy device corresponding to the subnet where the second host 642 is located are configured to obtain network information of the first host 640 and the second host 642, where the network information includes the MAC address. Address, IP address, and port information; and decide the forwarding path based on the information of the subnet.

Step 502: The first host sends a first ARP request to the first switch.

The first host 640 is to communicate with the second host 642. First, the MAC address of the second host 642 is queried according to the IP address of the second host 642. Therefore, the first host 640 constructs a first ARP request, and the first ARP request source MAC For the MAC of the first host 640, the source IP address is the IP address of the first host 640, the destination MAC address is 0, and the destination IP address is the IP address of the second host 642. The first host 640 sends the first ARP request to the first switch 660.

Correspondingly, the first switch 660 receives the first ARP request.

Step 503: The first switch queries the local forwarding flow table. If the forwarding flow table information corresponding to the received first ARP request is not found, the first switch sends the information to the controller in the form of a packet input message. The destination IP address in the first ARP request is queried locally. The forwarding flow table, if the forwarding flow table information corresponding to the destination IP address is queried, is forwarded according to the forwarding flow table information; if the forwarding flow table information corresponding to the destination IP address is not queried, the received An ARP request is sent to the controller 620 in the form of a packet input message.

Correspondingly, the controller 620 receives the first ARP request.

Step 504: The controller acquires the network information of the first host by using the received first ARP request. The controller 620 acquires the MAC address and the IP address of the first host 640 according to the received first ARP request, and the first host 640 is obtained. The MAC address and the IP address are used as the network information of the first host 640. Since the first ARP request is sent to the controller 620 in the form of a packet input message, the controller 620 can also obtain the port of the first host 640 as needed. The information, the MAC address, the IP address, and the port information of the first host 640 are used as the network information of the first host 640. In other words, the network information of the first host 640 may include the MAC address and IP address of the first host 640, and may also include the MAC address, IP address, and port information of the first host 640.

Step 505: The controller constructs a first ARP response, and feeds back the first ARP response to the first host by using a switch connected to the first host.

Since the controller 620 implements the role of the first proxy device, the controller 620 actively constructs a first ARP response, when the first ARP request is received and the destination IP address is the IP address of the second host 142. The ARP response source MAC address is the MAC address of the first proxy device, the source IP address is the IP address of the second host 642, the destination MAC address is the MAC address of the first host 640, and the destination IP address is the IP address of the first host 640. The first ARP response is sent from the port of the first switch 660 to the first host 640 in the form of a packet output message.

Correspondingly, the first host 640 receives the first ARP response.

Step 506: The first host saves a MAC address of the first proxy device.

After receiving the first ARP response, the first host 640 saves the MAC address of the first proxy device in the first ARP response as the MAC address of the second host 642.

After the above steps 502 to 506, the first host 640 completes the ARP learning process between the first proxy device implemented by the controller 620.

Step 507: The first host sends a data packet whose destination host is the second host to the first switch. In step 506, the first host 640 has obtained the MAC address of the first proxy device, and And the MAC address of the first proxy device is saved as the MAC address of the second host 642, so the first host 640 sends the destination MAC address of the data packet to the second host 642 as the MAC address of the first proxy device. The IP address is the IP address of the second host 642, and the first host 640 sends the data packet to the first switch 660.

Correspondingly, the first switch 660 receives the data packet.

Step 508: The first switch queries the local forwarding flow table. If the forwarding flow table information corresponding to the data packet is not found, the first switch sends the information to the controller in the form of a packet input message.

The first switch 660 receives the data packet sent by the first host 640, and queries the local forwarding flow table according to the IP address in the data packet. If the forwarding flow table information corresponding to the destination IP address is queried, the information is forwarded according to the forwarding flow table information. Forwarding; if the forwarding flow table information corresponding to the destination IP address is not found, the data packet is sent to the controller 620 in the form of a packet input message.

Correspondingly, the controller 620 receives the data packet.

Step 509: The controller constructs a second ARP request according to the IP address of the second host, and sends the second ARP request to all hosts in the subnet where the second host is located through the switch in the subnet where the second host is located.

When the controller 620 receives the data packet, it does not know the MAC address of the second host 642. Since the controller 620 implements the role of the second proxy device, the destination IP address is received as the IP address of the second host 642. In the case of the data packet, the second ARP request is actively constructed. The second ARP request source MAC address is the MAC address of the second proxy device, the source IP address is the IP address of the first host 640, the destination MAC address is all zero, and the destination IP address is The IP address of the second host 642 is sent to all the subnets of the second host 642 in the form of a packet output message according to the gateway, the network number, and the subnet mask of the subnet where the second host 642 is located. Host.

Correspondingly, all the hosts in the subnet where the second host 642 is located receive the second ARP request, such as the second host 642, the third host 644 and the fourth host 646, wherein the three hosts 644 and the fourth host 646 are not in the Marked in Figure 5.

Step 510: The second host responds to the second ARP request.

The second host 642 receives the second ARP request sent by the second switch 662, and finds that the destination IP address in the second ARP request is the same as its own IP address, and then constructs a second ARP response. The second ARP response source MAC address is the MAC address of the second host 642, the source IP address is the IP address of the second host 642, the destination MAC address is the MAC address of the second proxy device, and the destination IP is the IP address of the first host 640. The address is sent by the second switch 662 to the controller 620 for the second ARP response.

Correspondingly, the controller 620 receives the second ARP response.

Step 51: The controller acquires network information of the second host.

The controller 620 obtains the MAC address and the IP address of the second host 642 according to the received second ARP response, and uses the MAC address and the IP address of the second host 642 as the network information of the second host 642; The controller 620 can also obtain the port information of the second host 642 as needed, and use the MAC address, IP address, and port information of the second host 642 as the second host 642. Network information. In other words, the network information of the second host 642 may include the MAC address and IP address of the second host 642, and may also include the MAC address, IP address, and port information of the second host 642.

After the above steps 507 to 51 1 , the controller completes the ARP learning process between the implemented second proxy device and the second host 642;

Step 512: The controller calculates a shortest forwarding path between the first host and the second host according to the network information of the first host and the network information of the second host. The shortest forwarding path is used as the forwarding between the first host and the second host. Path

The controller 620 analyzes the destination IP address of the data packet sent by the first switch 660, and finds that the destination host of the data packet, that is, the second host 642 and the first host 640 are in different subnets, and determines that it is a three-layer forwarding, and The MAC address, IP address, and port information of the first host 640 and the second host 642 are obtained through the ARP learning process, and the forwarding path is generated according to the routing algorithm decision. If the forwarding path is generated according to the shortest path policy, the generated forwarding path may be generated. The first switch 660 <-> the third switch 664 <-> the second switch 662. For example, when the network information of the first host 640 and the second host 642 includes the MAC address, the IP address, and the port information, the controller 620 can determine that the IP address of the first host 640 and the second host 642 is three-layer forwarding. Generating a forwarding path according to the routing algorithm decision, and assuming that the forwarding path is generated according to the shortest path policy, the forwarding path generated according to the port information of the first host 640 and the second host 642 It may be: a first switch 660<-> a third switch 664<-> a second switch 662. It should be noted that the controller 620 may further calculate an optimal forwarding path between the first host 640 and the second host 642 according to the network information of the first host 640 and the network information of the second host 642. The optimal forwarding path is a chain. The optimal path of the path is used as the forwarding path between the first host 640 and the second host 642. The shortest path policy is used as an example for description.

Step 513: The controller generates a corresponding forwarding flow table for the switch on the forwarding path according to the generated forwarding path, and sends the generated forwarding flow table to the corresponding switch.

The controller 620 generates a corresponding forwarding flow table for the switch on the forwarding path according to the generated forwarding path, and sends the generated forwarding flow table to the corresponding switch. For example, the controller 620 is the first switch 660 on the shortest path. The third switch 664 and the second switch 662 generate a corresponding forwarding flow table, and send the forwarding flow table corresponding to the first switch 660 to the first switch 660, and send the forwarding flow table corresponding to the third switch 664 to the third switch. 664. Send the forwarding flow table corresponding to the second switch 662 to the second switch 662. The third switch 664 is not labeled in Figure 5.

Step 514: The corresponding switch updates the local forwarding flow table according to the forwarding flow table.

For example, the first switch 660, the third switch 664, and the second switch 662 on the corresponding shortest path update the local forwarding flow table information.

Step 515: The corresponding switch forwards the communication data packet between the first host and the second host according to the updated forwarding flow table.

For example, the first switch 660, the third switch 664, and the second switch 662 on the corresponding shortest path forward the communication data packet between the first host 640 and the second host 642 according to the updated forwarding flow table.

In summary, the implementation method of the three-layer forwarding provided by the embodiment replaces the partial OpenFlow switch that implements the gateway/routing function in the OpenFlow network by using the controller, and the controller implements the first two subnets corresponding to the communication. The proxy ARP function of the proxy device and the second proxy device enables all switches in the OpenFlow network to implement a simple forwarding function, thereby solving the problem that the dedicated OpenFlow switch in the OpenFlow network cannot implement the gateway/routing function. There is no need to separately set up a switch functioning as a gateway/router in the OpenFlow network. Effect.

It should be noted that the control message can be transmitted between the controller and the switch through a dedicated network, and the communication path for forwarding data between the switch and the switch is isolated on the physical link; or the communication path for forwarding data with the switch is the same path. Different rules are used to distinguish between control messages between the controller and the switch and forwarding data between the switches. The following is an embodiment of the device of the present invention, and the content that is not described in detail may be referred to the corresponding method embodiment.

Embodiment 4

Please refer to FIG. 7 , which is a schematic structural diagram of a controller according to Embodiment 4 of the present invention. The controller includes: a first information acquiring module 710, a second information acquiring module 720, a path generating module 730, and a flow table. Send module 740.

The first information obtaining module 710 is configured to acquire network information of the first host by using the received first ARP request, where the first ARP request is sent by the first host, and is related to the first host The connected switch cannot find the ARP request that is forwarded to the controller after forwarding the flow table. The second information obtaining module 720 is configured to acquire the network information of the second host by constructing the second ARP request.

The path generation module 730 is configured to generate, according to the network information of the first host acquired by the first information acquiring module 710 and the network information of the second host acquired by the second information acquiring module 720. a forwarding path between a host and the second host;

The flow table issuing module 740 is configured to send a forwarding flow table to each switch on the forwarding path generated by the path generation module 730, so that each switch on the forwarding path is in accordance with the forwarding flow table. Transmitting a data packet between the first host and the second host.

In summary, the controller provided in this embodiment generates a forwarding path according to the obtained network information of the first host and the second host by acquiring the network information of the first host and the second host, so that the first host and the first host and The second host communicates, which solves the problem that the dedicated OpenFlow switch in the OpenFlow network cannot implement the function, and achieves the effect that the switch that does not need to be separately set to the gateway/route function is required in the OpenFlow network. Embodiment 5

Please refer to FIG. 8, which is a schematic structural diagram of a controller provided in Embodiment 5 of the present invention. This embodiment is mainly illustrated by the application of the controller to the implementation environment shown in FIG. Referring to FIG. 4, the implementation environment includes a controller 420, a first host 440, a second host 442, a third host 444, and a fourth host 446, a first switch 460, a second switch 462, a third switch 464, and a fourth The switch 466 and the fifth switch 468, wherein the first host 440 belongs to the first subnet, the second host 442, the third host 444, and the fourth host 446 belong to the second subnet, and the first host 440 and the third host 444 are connected to On the port of the first switch 460, the second host 442 is connected to the port of the second switch 462, and the fourth host 446 is connected to the port of the fifth switch 468. The second host 442 is configured as a second gateway, the first host 440 belongs to the first subnet, and the second host 442, the third host 444, and the fourth host 446 belong to the second subnet, and the first gateway and the second gateway are controlled. The 420 is implemented on the controller 420, and the information about the subnet where the first host 440 and the second host 442 are located (including the gateway, the network number, and the subnet mask) and corresponding Gateway information (including IP address and MAC address of the gateway). The controller includes: a first pre-storage module 810, a first information acquisition module 820, a first feedback module 830, a second information acquisition module 840, a path generation module 850, and a flow table delivery module 860.

The first pre-storage module 810 is configured to pre-store a gateway, a network number, and a subnet mask of a subnet where the first host 440 and the second host 442 are located, and the first gateway and the second The MAC address and IP address of the gateway.

The first information obtaining module 820 is configured to acquire network information of the first host 440 by using the received first ARP request, where the first ARP request is sent by the first host 440, and the first A switch connected to a host 440 cannot find an ARP request forwarded to the controller 420 after forwarding the flow table.

Specifically, the first information acquiring module 820 includes: a fourth receiving unit 821 and a first acquiring unit 822.

The fourth receiving unit 821 is configured to receive the first ARP request sent by the first host 440. The first obtaining unit 822 is configured to acquire network information of the first host 440 by using the first ARP request received by the fourth receiving unit 821.

The first feedback module 830 is configured to feed back a first ARP response to the first host 440 by using a switch connected to the first host 440, where a source MAC address and a source IP address in the first ARP response are respectively Is the MAC address and IP address of the first gateway.

The second information acquiring module 840 is configured to acquire network information of the second host 442 by constructing a second ARP request.

Specifically, the second information acquiring module 840 includes: a first receiving unit 841, a first constructing unit 842, a first sending unit 843, a second receiving unit 844, and a second acquiring unit 845.

The first receiving unit 841 is configured to receive a data packet sent by the first host 440, where a destination MAC address of the data packet is a MAC address of the first gateway, and a destination IP address is the second host 442. IP address.

The first constructing unit 842 is configured to construct a second ARP request according to an IP address of the second host 442 in the data packet received by the first receiving unit 841, a source MAC address and a source of the second ARP request. The IP address is the MAC address and the IP address of the second gateway, the destination IP address is the IP address of the second host 442, and the second gateway is the configuration gateway of the second host 442.

The first sending unit 843 is configured to use, according to the gateway, the network number, and the subnet mask of the subnet where the second host 442 is pre-stored by the first pre-storage module 810, by using the second host 442 in the subnet The switch sends the second ARP request constructed by the first construction unit 842 to all hosts in the subnet where the second host 442 is located.

The second receiving unit 844 is configured to receive, by using a switch connected to the second host 442, a second ARP response that is sent by the second host 442, where the source MAC address and the source IP address of the second ARP response are respectively It is the MAC address and IP address of the second host 442.

The second obtaining unit 845 is configured to acquire network information of the second host 442 according to the second ARP response received by the second receiving unit 844.

The path generation module 850 is configured to: according to the network information of the first host 440 acquired by the first information acquiring module 820 and the second host acquired by the second information acquiring module 840 The network information decision of 442 generates a forwarding path between the first host 440 and the second host 442.

Specifically, the path generation module 850 specifically includes: a shortest generation unit 851, or an optimal generation unit 852.

The shortest generation unit 851 is configured to calculate, according to the network information of the first host 440 acquired by the first information acquiring module 820 and the network information of the second host 442 acquired by the second information acquiring module 840. The shortest forwarding path between the first host 440 and the second host 442; the shortest forwarding path is used as a forwarding path between the first host 440 and the second host 442.

The optimal generation unit 852 is configured to calculate, according to the network information of the first host 440 acquired by the first information acquiring module 820 and the network information of the second host 442 acquired by the second information acquiring module 840. An optimal forwarding path between the first host 440 and the second host 442; the optimal forwarding path is used as a forwarding path between the first host 440 and the second host 442.

The flow table issuing module 860 is configured to deliver a forwarding flow table to each switch on the forwarding path generated by the path generation module 850, so that each switch on the forwarding path is in accordance with the forwarding flow table. The data packet is forwarded between the first host 440 and the second host 442.

In summary, the controller provided in this embodiment obtains network information of the first host and the second host by implementing the ARP function of the first gateway and the second gateway, according to the first host and the pre-stored The information about the subnet where the second host is located and the corresponding gateway information and the obtained network information of the first host and the second host determine a forwarding path, so that all switches in the OpenFlow network can implement a simple forwarding function, thereby solving The dedicated OpenFlow switch in the OpenFlow network cannot implement the gateway/routing function, and the effect of the switch that does not need to be separately set to the gateway/routing function in the OpenFlow network is achieved. Embodiment 6

Please refer to FIG. 9, which is a schematic structural diagram of a controller provided in Embodiment 6 of the present invention. This embodiment is mainly illustrated by the application of the controller to the implementation environment shown in FIG. 6. Refer to Figure 6 The implementation environment includes a controller 620, a first host 640, a second host 642, a third host 644, and a fourth host 646, a first switch 660, a second switch 662, a third switch 664, a fourth switch 666, and The fifth switch 668, wherein the first host 640 belongs to the first subnet, the second host 642, the third host 644, and the fourth host 646 belong to the second subnet, and the first host 640 and the third host 644 are connected to the first switch. On the port of 660, the second host 642 is connected to the port of the second switch 662, and the fourth host 646 is connected to the port of the fifth switch 668. It is assumed that the first host 640 and the second host 642 are not configured with a default gateway. The host 640 belongs to the first subnet, and the second host 642, the third host 644, and the fourth host 646 belong to the second subnet. The controller 620 pre-stores information about the subnet where the first host 640 and the second host 642 are located ( The gateway, the network number, and the subnet mask are included, and the first proxy device and the second proxy device respectively correspond to the two subnets. The controller includes: a second pre-storage module 910, a first information acquisition module 920, a second feedback module 930, a second information acquisition module 940, a path generation module 950, and a flow table delivery module 960.

The second pre-storage module 910 is configured to pre-store a gateway, a network number, and a subnet mask of a subnet where the first host 640 and the second host 642 are located, and the first proxy device and the first The MAC address of the second proxy device.

The first information obtaining module 920 is configured to acquire network information of the first host 640 by using the received first ARP request, where the first ARP request is sent by the first host 640 and is related to the first A switch connected to a host 640 cannot find an ARP request forwarded to the controller 620 after forwarding the flow table.

Specifically, the first information acquiring module 920 includes: a fourth receiving unit 921 and a first acquiring unit 922.

The fourth receiving unit 921 is configured to receive the first ARP request sent by the first host 640.

The first obtaining unit 922 is configured to acquire network information of the first host 440 by using the first ARP request received by the fourth receiving unit 921.

The second feedback module 930 is configured to feed back, by the switch connected to the first host 640, the first ARP response to the first host 640, where the source MAC address in the first ARP response is the first proxy device. MAC address, the source IP address is the IP address of the second host, so as to The first host 640 uses the MAC address of the first proxy device as the MAC address of the second host 642, and the first proxy device is a proxy device corresponding to the subnet in which the first host 640 is located.

The second information acquiring module 940 is configured to acquire network information of the second host 642 by constructing a second ARP request.

Specifically, the second information acquiring module 940 includes: a third receiving unit 941, a second constructing unit 942, a second sending unit 943, a second receiving unit 944, and a second obtaining unit 945.

The third receiving unit 941 is configured to receive a data packet sent by the first host 640, where a destination MAC address of the data packet is a MAC address of the first proxy device, and a destination IP address is the second host 642 IP address.

The second constructing unit 942 is configured to construct a second ARP request according to the IP address of the second host 642 in the data packet received by the third receiving unit 941, where the source MAC address of the second ARP request is The MAC address of the second proxy device, the source IP address being the IP address of the first host 640, and the destination IP address being the IP address of the second host 642, so that the second host 642 will be the second proxy device The MAC address is used as the MAC address of the first host 640, and the second proxy device is a proxy device corresponding to the subnet in which the second host 642 is located.

The second sending unit 943 is configured to send, by using a switch in a subnet where the second host 642 is located, a second ARP request configured by the second configuration unit 942 to a subnet in which the second host 642 is located. All hosts.

The second receiving unit 944 is configured to use a switch connected to the second host 642 according to a gateway, a network number, and a subnet mask of a subnet where the second host 642 is pre-stored by the second pre-storage module 910. And receiving, by the second host 642, the second ARP response, where the source MAC address and the source IP address of the second ARP response are respectively the MAC address IP address of the second host 642.

The second obtaining unit 945 is configured to acquire network information of the second host 642 according to the second ARP response received by the second receiving unit 944.

The path generation module 950 is configured to generate, according to the network information of the first host 640 acquired by the first information acquiring module 920 and the network information decision generation of the second host 642 acquired by the second information acquiring module 940. Forwarding between the first host 640 and the second host 642 Path.

Specifically, the path generation module 950 specifically includes: a shortest generation unit 951, or an optimal generation unit 952.

The shortest generation unit 951 is configured to calculate, according to the network information of the first host 640 acquired by the first information acquiring module 920 and the network information of the second host 642 acquired by the second information acquiring module 940. The shortest forwarding path between the first host 640 and the second host 642; the shortest forwarding path is used as a forwarding path between the first host 640 and the second host 642.

The optimal generation unit 952 is configured to calculate, according to the network information of the first host 640 acquired by the first information acquiring module 920 and the network information of the second host 642 acquired by the second information acquiring module 940. The optimal forwarding path between the first host 640 and the second host 642 is used as the forwarding path between the first host 640 and the second host 642.

The flow table issuing module 960 is configured to send a forwarding flow table to each switch on the forwarding path generated by the path generating module 950, so that each switch on the forwarding path is in accordance with the forwarding flow table. The data packet is forwarded between the first host 640 and the second host 642.

In summary, the controller provided by the embodiment obtains the network information of the first host and the second host by implementing the proxy ARP function of the first proxy device and the second proxy device, according to the first host stored in advance. And the information about the subnet where the second host is located and the corresponding gateway information and the obtained network information of the first host and the second host determine a forwarding path, so that all switches in the OpenFlow network can implement a simple forwarding function. Therefore, the problem that the dedicated OpenFlow switch in the OpenFlow network cannot implement the gateway/routing function is solved, and the effect that the switch functioning as the gateway/routing function is not required in the OpenFlow network is achieved.

It should be noted that, when the controller provided by the foregoing embodiment generates the forwarding path, only the division of the foregoing functional modules is illustrated. In actual applications, the foregoing function allocation may be completed by different functional modules as needed. The internal structure of the controller is divided into different functional modules to perform all or part of the functions described above. In addition, the controller and the method for generating a forwarding path provided by the foregoing embodiments are in the same concept, and the specific implementation process is described in the method embodiment. I won't go into details here. Example 7

Referring to FIG. 10, a block diagram showing the structure of a forwarding path generating system provided in Embodiment 7 of the present invention is shown. The system includes the controller 1010, the first host 1020, and the second host 1030 provided in the fifth embodiment or the sixth embodiment.

In summary, the system for generating a forwarding path provided by the embodiment obtains the network information of the first host and the second host by using the controller, and generates a forwarding path according to the obtained network information of the first host and the second host. In order to communicate between the first host and the second host, the problem that the dedicated OpenFlow switch in the OpenFlow network cannot implement the function is solved, and the effect that the switch functioning as the gateway/routing function is not required in the OpenFlow network is achieved. Example eight

Referring to FIG. 1, a block diagram of a controller provided in Embodiment 8 of the present invention is shown. The controller includes: a processor 1 101 and a transmitter 1 102.

The processor 1101 is configured to acquire network information of the first host by using the received first ARP request, where the first ARP request is sent by the first host and connected to the first host. The switch cannot find the ARP request forwarded to the controller after forwarding the flow table.

The processor 1101 is further configured to acquire network information of the second host by constructing a second ARP request.

The processor 1101 is further configured to generate, according to the acquired network information of the first host and the network information of the second host, a forwarding path between the first host and the second host.

The transmitter 1102 is configured to send, to each switch on the forwarding path generated by the processor 1 101, a forwarding flow table, so that each switch on the forwarding path is configured according to the forwarding flow table. A data packet is forwarded between the first host and the second host.

In summary, the controller provided in this embodiment generates a forwarding path according to the obtained network information of the first host and the second host by acquiring the network information of the first host and the second host, so that the first host and the first host and The second host communicates and resolves the dedicated one in the OpenFlow network. The OpenFlow switch cannot implement the problem of this function, and the effect of the switch that does not need to be separately set to the gateway/routing function in the OpenFlow network is achieved. Example nine

Referring to FIG. 12, a block diagram showing the structure of a controller provided in Embodiment 9 of the present invention is shown. This embodiment is mainly illustrated by the application of the controller to the implementation environment shown in FIG. The controller includes: a memory 1201, a processor 1202, a transmitter 1203, and a receiver 1204.

The memory 1201 is configured to pre-store a gateway, a network number, and a subnet mask of a subnet where the first host 440 and the second host 442 are located, and a MAC address of the first gateway and the second gateway. And IP address.

The processor 1202 is configured to obtain network information of the first host 440 by using the received first ARP request, where the first ARP request is sent by the first host 440 and is related to the first host 440. The connected switch cannot find the ARP request forwarded to the controller 420 after forwarding the flow table.

Specifically, the processor 1202 is specifically configured to control the receiver 1204 to receive the first ARP request sent by the first host 440. The processor 1202 is further configured to acquire network information of the first host 440 by using the first ARP request received by the receiver 1204.

The transmitter 1203 is configured to feed back, by the switch connected to the first host 440, the first ARP response to the first host 440, where the source MAC address and the source IP address in the first ARP response are respectively The MAC address and IP address of the first gateway.

The processor 1202 is further configured to acquire network information of the second host 442 by constructing a second ARP request.

Specifically, the processor 1202 is specifically configured to control the receiver 1204 to receive a data packet sent by the first host 440, where a destination MAC address of the data packet is a MAC address of the first gateway, and The IP address is the IP address of the second host 442. The processor 1202 is further configured to construct a second ARP request according to the IP address of the second host 442 in the data packet received by the receiver 1204. The source MAC address and the source IP address of the second ARP request are respectively the MAC address and the IP address of the second gateway, and the destination IP address is the IP of the second host 442. The second gateway is a configuration gateway of the second host 442. The processor 1202 is further configured to control a subnet where the second host 442 is pre-stored by the transmitter 1203 according to the memory 1201. a gateway, a network number, and a subnet mask, where the second ARP request is sent to all hosts in the subnet where the second host 442 is located by using a switch in the subnet where the second host 442 is located; the processor 1202 The receiver 1202 is further configured to receive, by using a switch connected to the second host 442, a second ARP response fed back by the second host 442, a source MAC address and a source IP address of the second ARP response. The processor is configured to obtain the network information of the second host 442 according to the second ARP response received by the receiver 1204.

The processor 1202 is further configured to generate the first host 440 and the second host 442 according to the acquired network information of the first host 440 and the acquired network information of the second host 442. The forwarding path between.

In particular, the processor 1202 is further configured to calculate the first host 440 and the network according to the acquired network information of the first host 440 and the acquired network information of the second host 442. The shortest forwarding path between the second host 442; the shortest forwarding path is used as a forwarding path between the first host 440 and the second host 442; or the processor 1202 is further configured to be used according to Calculating the optimal forwarding path between the first host 440 and the second host 442 by using the acquired network information of the first host 440 and the acquired network information of the second host 442; The optimal forwarding path is used as a forwarding path between the first host 440 and the second host 442.

The processor 1202 is further configured to send a forwarding flow table to each switch on the generated forwarding path, so that each switch on the forwarding path is in the first host 440 according to the forwarding flow table. And forwarding the data packet with the second host 442.

In summary, the controller provided in this embodiment obtains network information of the first host and the second host by implementing the ARP function of the first gateway and the second gateway, according to the first host and the pre-stored The information about the subnet where the second host is located and the corresponding gateway information and the obtained network information of the first host and the second host determine a forwarding path, so that all switches in the Open Flow network can implement a simple forwarding function. Resolved a dedicated in the OpenFlow network The OpenFlow switch cannot implement the problem of the gateway/routing function, and the effect of the switch that does not need to be separately set to the gateway/routing function in the OpenFlow network is achieved. Example ten

Referring to FIG. 12, it shows a structural block diagram of a controller provided in Embodiment 10 of the present invention. This embodiment is mainly illustrated by the application of the controller to the implementation environment shown in FIG. 6. The controller includes: a memory 1201, a processor 1202, a transmitter 1203, and a receiver 1204.

The memory 1201 is configured to pre-store a gateway, a network number, and a subnet mask of a subnet where the first host 640 and the second host 642 are located, and the first proxy device and the second proxy device. MAC address.

The processor 1202 is configured to acquire network information of the first host 640 by using the received first ARP request, where the first ARP request is sent by the first host 640 and is related to the first host 640 The connected switch cannot find the ARP request forwarded to the controller 620 after forwarding the flow table.

Specifically, the processor 1202 is specifically configured to control the receiver 1204 to receive the first ARP request sent by the first host 640. The processor 1202 is further configured to pass the receiver. The received first ARP request of 1204 acquires network information of the first host 440.

The transmitter 1203 is configured to feed back, by the switch connected to the first host 640, the first ARP response to the first host 640, where the source MAC address in the first ARP response is the MAC address of the first proxy device. The address, the source IP address is the IP address of the second host, so that the first host 640 uses the MAC address of the first proxy device as the MAC address of the second host 642, and the first proxy device corresponds to the The proxy device in the subnet where the first host 640 is located.

The processor 1202 is further configured to acquire network information of the second host 642 by constructing a second ARP request.

Specifically, the processor 1202 is specifically configured to control the receiver 1204 to receive a data packet sent by the first host 640, where a destination MAC address of the data packet is a MAC address of the first proxy device, The destination IP address is the IP address of the second host 642. The processor 1202 is further configured to use the second host 642 in the data packet received by the receiver 1204. The IP address of the second ARP request is configured, the source MAC address of the second ARP request is the MAC address of the second proxy device, the source IP address is the IP address of the first host 640, and the destination IP address is the second The IP address of the host 642, so that the second host 642 uses the MAC address of the second proxy device as the MAC address of the first host 640, and the second proxy device corresponds to the second host 642. The proxy device in the subnet; the processor 1202 is further configured to control the sender 1203 to send the second ARP request to the second host by using a switch in a subnet where the second host 642 is located The processor 1202 is further configured to control, according to the gateway, the network number, and the subnet mask of the subnet where the second host 642 is pre-stored by the receiver 1204 according to the memory 1201. The second ARP response fed back by the second host 642 is received by the switch connected to the second host 642, where the source MAC address and the source IP address of the second ARP response are respectively the MAC address of the second host 642. IP address; Processor 1202 is also configured to acquire the second host network response information 642 according to the second ARP received by the receiver 1204.

The processor 1202 is further configured to generate the first host 640 and the second host 642 according to the acquired network information of the first host 640 and the acquired network information of the second host 642. The forwarding path between.

Specifically, the processor 1202 is specifically configured to calculate, according to the acquired network information of the first host 640 and the acquired network information of the second host 642, the first host 640 and the first The shortest forwarding path between the two hosts 642; the shortest forwarding path is used as a forwarding path between the first host 640 and the second host 642; or the processor 1202 is further configured to be used according to the Calculating the optimal forwarding path between the first host 640 and the second host 642 by calculating the obtained network information of the first host 640 and the acquired network information of the second host 642; The forwarding path is used as a forwarding path between the first host 640 and the second host 642.

The transmitter 1203 is further configured to send, to each switch on the forwarding path generated by the processor 1202, a forwarding flow table, so that each switch on the forwarding path is in the foregoing according to the forwarding flow table. A data packet is forwarded between a host 640 and the second host 642.

In summary, the controller provided in this embodiment implements the first proxy device and the second proxy. The proxy ARP function of the device acquires network information of the first host and the second host, according to pre-stored information of the first host and the second host where the second host is located, and corresponding gateway information and the obtained first host The network information of the second host determines the forwarding path, so that all the switches in the OpenFlow network can implement the simple forwarding function, thereby solving the problem that the dedicated OpenFlow switch in the OpenFlow network cannot implement the gateway/routing function. There is no need to separately set the effect of the switch functioning as a gateway/routing function in the OpenFlow network.

The serial numbers of the embodiments of the present invention are merely for the description, and do not represent the advantages and disadvantages of the embodiments.

A person skilled in the art may understand that all or part of the steps of implementing the above embodiments may be completed by hardware, or may be instructed by a program to execute related hardware, and the program may be stored in a computer readable storage medium. The storage medium mentioned may be a read only memory, a magnetic disk or an optical disk or the like.

The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., which are within the spirit and scope of the present invention, should be included in the protection of the present invention. Within the scope.

Claims

claims

1. A method for generating a forwarding path, characterized in that it is used in an OpenFlow network including a controller and at least one switch, and the method includes:

The controller obtains the network information of the first host through the received first ARP request. The first ARP request is sent by the first host and the switch connected to the first host cannot find the forwarding flow table. and then forward the ARP request to the controller;

The controller obtains the network information of the second host by constructing a second ARP request;

The controller decides to generate a forwarding path between the first host and the second host based on the network information of the first host and the network information of the second host;

The controller delivers a forwarding flow table to each switch on the forwarding path, so that each switch on the forwarding path communicates between the first host and the second host according to the forwarding flow table. Forward the packet.

2. The method according to claim 1, characterized in that, if the destination IP address in the first ARP request is the IP address of the first gateway, and the first gateway is the configuration gateway of the first host, Then, after obtaining the network information of the first host through the received first ARP request, it further includes: the controller feeds back the first ARP response to the first host through the switch connected to the first host, so The source MAC address and source IP address in the first ARP response are the MAC address and IP address of the first gateway respectively.

3. The method according to claim 2, wherein the controller obtains the network information of the second host by constructing a second ARP request, including:

The controller receives the data packet sent by the first host, the destination MAC address of the data packet is the MAC address of the first gateway, and the destination IP address is the IP address of the second host;

The controller constructs a second ARP request according to the IP address of the second host. The source MAC address and source IP address of the second ARP request are the MAC address and IP address of the second gateway respectively, and the destination IP address is the The IP address of the second host, the second gateway is the configuration gateway of the second host; the controller sends the second ARP request to the second host through the switch in the subnet where the second host is located. All hosts in the subnet where the second host is located;

The controller receives the second feedback from the second host through a switch connected to the second host. Two ARP responses, the source MAC address and the source IP address of the second ARP response are the MAC address and IP address of the second host respectively.

4. The method according to claim 3, wherein before the controller obtains the network information of the first host through the received first ARP request, it further includes:

The controller pre-stores the gateway, network number and subnet mask of the subnet where the first host and the second host are located, as well as the MAC address and IP address of the first gateway and the second gateway; The controller sends the second ARP request to all hosts in the subnet where the second host is located through the switch of the subnet where the second host is located, including;

The controller sends the second ARP request to all hosts in the subnet where the second host is located based on the gateway, network number and subnet mask of the subnet where the second host is located.

5. The method according to claim 1, characterized in that, if the destination IP address in the first ARP request is the IP address of the second host, then the first ARP request received is obtained. After the network information of a host, it also includes:

The controller feeds back a first ARP response to the first host through a switch connected to the first host. The source MAC address in the first ARP response is the MAC address of the first proxy device, and the source IP address is The IP address of the second host, so that the first host uses the MAC address of the first proxy device as the MAC address of the second host, and the first proxy device is located corresponding to the location of the first host. Proxy device within the subnet.

6. The method according to claim 5, wherein the controller obtains the network information of the second host by constructing a second ARP request, including:

The controller receives the data packet sent by the first host, the destination MAC address of the data packet is the MAC address of the first proxy device, and the destination IP address is the IP address of the second host; the control The device constructs a second ARP request according to the IP address of the second host, the source MAC address of the second ARP request is the MAC address of the second proxy device, the source IP address is the IP address of the first host, and the destination IP The address is the IP address of the second host, so that the second host uses the MAC address of the second proxy device as the MAC address of the first host, and the second proxy device is the IP address corresponding to the second host. The proxy device in the subnet where the host is located; The controller sends the second ARP request to all hosts in the subnet where the second host is located through the switch in the subnet where the second host is located;

The controller receives a second ARP response fed back by the second host through a switch connected to the second host. The source MAC address and source IP address of the second ARP response are respectively the MAC of the second host. Address IP address.

7. The method according to claim 6, wherein before the controller obtains the network information of the first host through the received first ARP request, it further includes:

The controller pre-stores the gateway, network number and subnet mask of the subnet where the first host and the second host are located, as well as the MAC addresses of the first proxy device and the second proxy device; The controller sends the second ARP request to all hosts in the subnet where the second host is located through the switch in the subnet where the second host is located, including;

8. The method according to any one of claims 1 to 7, characterized in that: the decision to generate the first host and the second host is based on the network information of the first host and the network information of the second host. The forwarding path between the two hosts includes:

Calculate the shortest forwarding path between the first host and the second host according to the network information of the first host and the network information of the second host; use the shortest forwarding path as the first host and the second host. The forwarding path between the second hosts;

or;

Calculate the optimal forwarding path between the first host and the second host according to the network information of the first host and the network information of the second host; use the optimal forwarding path as the first The forwarding path between the host and the second host.

9. A controller, characterized in that it is used in an OpenFlow network including at least one switch, and the controller includes:

A first information acquisition module, configured to obtain the network information of the first host through the received first ARP request, the first ARP request being sent by the first host and connected to the first host The switch cannot find the forwarding flow table and forward the ARP request to the controller;

The second information acquisition module is used to obtain the network information of the second host by constructing a second ARP request; the path generation module is used to obtain the network information of the first host and the second host according to the first information acquisition module. The network information decision of the second host obtained by the information acquisition module generates a forwarding path between the first host and the second host;

A flow table delivery module, configured to deliver a forwarding flow table to each switch on the forwarding path generated by the path generation module, so that each switch on the forwarding path generates a forwarding flow table in the first step according to the forwarding flow table. Data packets are forwarded between the host and the second host.

10. The controller according to claim 9, wherein if the destination IP address in the first ARP request is the IP address of the first gateway, the first gateway is the configuration gateway of the first host. , the controller also includes:

A first feedback module, configured to feed back a first ARP response to the first host through a switch connected to the first host, where the source MAC address and source IP address in the first ARP response are respectively the first The MAC address and IP address of the gateway.

11. The controller according to claim 10, characterized in that the second information acquisition module includes:

The first receiving unit is used to receive the data packet sent by the first host, the destination MAC address of the data packet is the MAC address of the first gateway, and the destination IP address is the IP address of the second host;

A first construction unit configured to construct a second ARP request based on the IP address of the second host in the data packet received by the first receiving unit, where the source MAC address and source IP address of the second ARP request are respectively the first The MAC address and IP address of the second gateway, the destination IP address is the IP address of the second host, and the second gateway is the configuration gateway of the second host;

The first sending unit is configured to send the second ARP request constructed by the first construction unit to all hosts in the subnet where the second host is located through the switch in the subnet where the second host is located;

A second receiving unit configured to receive a second ARP response fed back by the second host through a switch connected to the second host, where the source MAC address and source IP address of the second ARP response are respectively the second The host's MAC address and IP address.

12. The controller according to claim 11, characterized in that, the controller further includes: a first pre-storage module, configured to pre-store the gateway of the subnet where the first host and the second host are located. , network number and subnet mask, and the MAC address and IP address of the first gateway and the second gateway;

The first sending unit is specifically configured to send the second ARP request to the second host according to the gateway, network number and subnet mask of the subnet where the second host is located pre-stored by the first pre-storage module. All hosts in the subnet.

13. The controller according to claim 9, wherein if the destination IP address in the first ARP request is the IP address of the second host, the controller further includes:

The second feedback module is configured to feed back a first ARP response to the first host through a switch connected to the first host, where the source MAC address in the first ARP response is the MAC address of the first proxy device, source The IP address is the IP address of the second host, so that the first host uses the MAC address of the first proxy device as the MAC address of the second host, and the first proxy device is corresponding to the first proxy device. A proxy device within the subnet where a host is located.

14. The controller according to claim 13, characterized in that the second information acquisition module includes:

The third receiving unit is configured to receive the data packet sent by the first host, the destination MAC address of the data packet is the MAC address of the first proxy device, and the destination IP address is the IP address of the second host;

A second construction unit configured to construct a second ARP request based on the IP address of the second host in the data packet received by the third receiving unit, where the source MAC address of the second ARP request is the MAC of the second proxy device. address, the source IP address is the IP address of the first host, and the destination IP address is the IP address of the second host, so that the second host uses the MAC address of the second proxy device as the first host MAC address, the second proxy device is a proxy device corresponding to the subnet where the second host is located;

The second sending unit is configured to send the second ARP request constructed by the second construction unit to all hosts in the subnet where the second host is located through the switch in the subnet where the second host is located; A second receiving unit configured to receive a second ARP response fed back by the second host through a switch connected to the second host, where the source MAC address and source IP address of the second ARP response are respectively the second The host's MAC address IP address.

15. The controller according to claim 14, characterized in that, the controller further includes: a second pre-storage module, configured to pre-store the gateway of the subnet where the first host and the second host are located. , network number and subnet mask, and the MAC addresses of the first proxy device and the second proxy device;

The second sending unit is specifically configured to send the second ARP request to the second host according to the gateway, network number and subnet mask of the subnet where the second host is located pre-stored by the second pre-storage module. All hosts in the subnet.

16. The controller according to any one of claims 9 to 15, characterized in that the path generation module includes:

The shortest generation unit is configured to calculate the first host and the third host according to the network information of the first host acquired by the first information acquisition module and the network information of the second host acquired by the second information acquisition module. The shortest forwarding path between two hosts; using the shortest forwarding path as the forwarding path between the first host and the second host;

or;

The optimal generation unit is configured to calculate the first host and the first host according to the network information of the first host acquired by the first information acquisition module and the network information of the second host acquired by the second information acquisition module. The optimal forwarding path between the second hosts; using the optimal forwarding path as the forwarding path between the first host and the second host.

17. A forwarding path generation system, characterized in that the system includes the controller according to any one of claims 9 to 16, a first host and a second host. .