WO2016112640A1

WO2016112640A1 - Sdn-based wlan hierarchical networking system and method

Info

Publication number: WO2016112640A1
Application number: PCT/CN2015/081930
Authority: WO
Inventors: 吴方; 雷永成; 张志飞
Original assignee: 成都西加云杉科技有限公司
Priority date: 2015-01-13
Filing date: 2015-06-19
Publication date: 2016-07-21
Also published as: CN104582004A; CN104582004B

Abstract

The present invention provides an SDN-based WLAN hierarchical networking system and method. The SDN-based WLAN hierarchical networking system comprises an SDN controller and an AC in communication connection to the SDN controller. The AC serves as a controller of APs connected to the AC and serves as a switching node of the SDN controller. The AC creates virtual ports for the APs, sets the states of the virtual ports of all the APs according to the current network environment and reports the states to the SDN controller; the SDN controller is used for generating management state information according to the states of the virtual ports and sending the management state information to the AC; the AC is further used for converting management information, corresponding to the APs, in the management state information into a CAPWAP message and delivering the message to the APs. Accordingly, a hierarchical WLAN network architecture integrating the SDN controller, the AC and the APs is realized, WLAN services can be migrated to an SDN conveniently, investment of existing equipment is protected, the advantages of the SDN technology can also be fully utilized, and the practicality is good.

Description

SDN hierarchical networking system and method based on SDN

Technical field

The present invention relates to the field of communications, and in particular to an SDN-based WLAN hierarchical networking system and method.

Background technique

The WLAN (Wireless Local Area Networks) networking scheme includes two types: a fat AP (Access Pointer) network and a thin AP+AC (Access Controller) network. In the thin AP+AC networking solution, the AC centrally manages the AP, and the control data needs to pass through the AC. The service data is determined according to the need to be processed by the AC. The AC assumes the function of a part of the BRAS (Broadband Remote Access Server). It has the advantages of good manageability, support for roaming handover, and large-scale deployment, and has been widely used in carrier networks and large enterprises. The disadvantage is that AC is the bottleneck of the entire network, and the physical area of the thin AP managed by the AC. Limited, the number of AC devices required is relatively high, and network device resource utilization is not high.

The related technology provides a new type of network innovation architecture, SDN (Software Defined Network), which realizes flexible control of network traffic by separating the control plane of the network device from the data plane. SDN has hardware standardization, low networking cost, high network resource utilization, flexible network planning, design and management. Because SDN has the above characteristics compared with thin AP+AC networking, it attracts more and more networks. Equipment manufacturer's interest.

At present, for most investors who have invested in WLAN networking solutions, if they choose SDN, they need to abandon WLAN networking and re-invest in SDN, which will cause investors to waste money in WLAN networking; In the technology, a solution for converting the existing thin AP+AC networking scheme into an SDN is introduced. For example, the AC is componentized and deployed on the cloud server to provide the traditional thin AP+AC networking access function. The AC acts as the CONTROLLER (controller) of the SDN, and the thin AP works as the SWITCH node (switch) of the SDN (such as Ruckus). In this mode, the thin AP+AC adopts the CAPWAP protocol and the traditional data communication mode, and the existing In SDN, there is a difference in the system that separates the control plane of the network device from the data plane. It is impossible to smoothly migrate the thin AP+AC architecture to the SDN. Another way is to abandon the AC, on the cloud server. Deploy AP management components to take full advantage of the cloud's powerful computing power and provide management for many AP nodes (such as ARUBA). The way of abandoning the AC makes the thin AP+AC solution have problems in supporting zero configuration, roaming and strong management, thus losing the advantages of the thin AP+AC solution itself.

The inventor found in the research that the technology of WLAN migration (for example, the above-mentioned thin AP+AC networking) to SDN is not ideal in terms of the degree of utilization of existing resources and function optimization. Propose an effective solution.

Summary of the invention

It is an object of the present invention to provide an SDN-based WLAN hierarchical networking system and method for improving the utilization of existing resources when WLAN networking is migrated to SDN, and optimizing system functions.

In a first aspect, an embodiment of the present invention provides a WLAN hierarchical networking system based on a software-defined network SDN, including: an SDN controller and an access controller AC, AC, which is in communication with the SDN controller, a controller of the connected access node AP and a switching node of the SDN controller;

The AC creates a virtual port for the AP. The AC is configured to set the state of the virtual port of each AP according to the current network environment, and report the status of the virtual port to the SDN controller.

The SDN controller is configured to receive the status of the virtual port, generate management status information according to the status of the virtual port, and send the management status information to the AC;

The AC is further configured to receive the management status information, and convert the management information of the corresponding AP in the management status information into a wireless access point control and configuration protocol CAPWAP message and send the message to the AP.

With reference to the first aspect, the embodiment of the present invention provides a first possible implementation manner of the first aspect, where the AC includes:

The network environment detecting module is configured to detect whether the current AP's CAPWAP channel is normal, and whether the current AP's radio frequency device is in a working working state;

The virtual port state setting module is configured to set the state of the virtual port of the current AP to the management working state when the current AP's CAPWAP channel is normal and the current AP's radio device is in the working state.

With reference to the first aspect, the embodiment of the present invention provides a second possible implementation manner of the first aspect, where the management status information includes: flow table configuration information, and the AC includes:

a flow table receiving module, configured to receive flow table configuration information delivered by the SDN controller;

The flow table processing module is configured to extract the local flow table information from the flow table configuration information, and send the extracted local flow table information to the data plane of the AC, and convert the flow table information of the corresponding AP in the flow table configuration information into a wireless connection. The inbound control and configuration protocol CAPWAP messages are delivered to the AP.

In conjunction with the first aspect, the first possible implementation of the first aspect, and any one of the possible implementations of the second possible implementation of the first aspect, the embodiment of the present invention provides the third aspect of the first aspect A possible implementation, wherein in the system, the communication protocol adopted between the SDN controller and the AC is the OPENFLOW protocol.

In a second aspect, the embodiment of the present invention further provides a communication method for applying the system of any one of the first aspects, comprising:

The access controller AC creates a virtual port for the access node AP connected thereto;

The AC sets the state of the virtual port of each AP according to the current network environment, and reports the state of the virtual port to the SDN controller of the software-defined network SDN.

The AC receives the management status information returned by the SDN controller, and converts the management information of the corresponding AP in the management status information into a wireless access point control and configuration protocol CAPWAP message and sends the information to the AP; wherein, the management status information is the SDN controller according to the virtual port. The state is generated.

With reference to the second aspect, the embodiment of the present invention provides a first possible implementation manner of the second aspect, where the AC sets the state of the virtual port of each AP according to the current network environment, including:

The AC detects whether the CAPWAP channel of the current AP is normal, and detects whether the radio device of the current AP is in a working state.

When the CAPWAP channel of the current AP is normal and the radio device of the current AP is in the working state, the AC sets the state of the virtual port of the current AP to the administrative working state.

With reference to the second aspect, the embodiment of the present invention provides a second possible implementation manner of the second aspect, where the management status information includes: flow table configuration information;

The AC converts the management information of the corresponding AP in the management status information into the wireless access point control and configuration protocol. The CAPWAP message is sent to the AP, including: the flow table configuration information sent by the AC receiving SDN controller; the AC extracts the configuration information from the flow table. The local flow table information is sent to the data plane of the AC, and the flow table information of the corresponding AP in the flow table configuration information is converted into a wireless access point control and configuration protocol CAPWAP message and sent to the AP.

With reference to the second aspect, the first possible implementation manner of the second aspect, and the second possible implementation manner of the second aspect, the embodiment of the present invention provides the third aspect of the second aspect A possible implementation, wherein the communication protocol adopted between the SDN controller and the AC is the OPENFLOW protocol.

In a third aspect, the embodiment of the present invention further provides a communication method for applying the system of any one of the first aspects, comprising:

The SDN controller of the software-defined network SDN receives the status of the virtual port reported by the access controller AC; wherein the virtual port is created by the AC for each access node AP connected thereto, and the state of the virtual port is AC according to the current network environment. Set

The SDN controller generates the management state information according to the state of the virtual port, and sends the management state information to the AC, so that the AC converts the management information of the corresponding AP in the management state information into a wireless access point control and configuration protocol CAPWAP message and sends the message to the AP. .

With reference to the third aspect, the embodiment of the present invention provides a first possible implementation manner of the third aspect, wherein a communication protocol between the SDN controller and the AC is an OPENFLOW protocol.

An SDN-based WLAN hierarchical networking system and method provided by the embodiment of the present invention, the AC can be an AP by using an AC that is in communication with the SDN controller as a switching node between the controller and the SDN controller of the AP connected thereto. A virtual port is created and the status of the virtual port of each AP is reported to the SDN controller, so that the SDN generates the management status information. After receiving the management status information, the AC converts the management information of the corresponding AP into a CAPWAP message and sends the information to the AP. Compared with the prior art, the AC is used as a controller of the AP and as an exchange section of the SDN controller, and implements a hierarchical WLAN network architecture of the SDN controller, the AC, and the AP, facilitating the WLAN service to the SDN. Migration can not only effectively utilize existing equipment, but also fully implement various functions in SDN technology, and has good practicability.

The above described objects, features and advantages of the present invention will become more apparent from the aspects of the appended claims.

DRAWINGS

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments will be briefly described below. It should be understood that the following drawings show only certain embodiments of the present invention, and therefore It should be seen as a limitation on the scope, and those skilled in the art can obtain other related drawings according to these drawings without any creative work.

FIG. 1 is a schematic structural diagram of an SDN-based WLAN hierarchical networking system according to an embodiment of the present invention;

2 is a schematic structural diagram of a basic framework of an SDN-based WLAN hierarchical networking system according to an embodiment of the present invention;

FIG. 3 is a schematic structural diagram of a network channel in an SDN-based WLAN hierarchical networking system according to an embodiment of the present invention;

FIG. 4 is a schematic diagram of an access network and a backup network in which an SDN controller manages a virtual CPE or a VAP through an AC in an SDN-based WLAN hierarchical networking system according to an embodiment of the present invention;

FIG. 5 is a flowchart of an SDN-based WLAN hierarchical networking method according to an embodiment of the present invention;

FIG. 6 is a flowchart of another SDN-based WLAN hierarchical networking method according to an embodiment of the present invention;

FIG. 7 is a flowchart of another SDN-based WLAN hierarchical networking method provided by an embodiment of the present invention.

The main component symbol description:

11, SDN controller; 12, AC; 13, AP, 14, network environment detection module; 15, network environment detection module.

detailed description

The technical solutions in the embodiments of the present invention are clearly and completely described in the following with reference to the accompanying drawings in the embodiments of the present invention. It is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. The components of the embodiments of the invention, which are generally described and illustrated in the figures herein, may be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the invention in the claims All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts are within the scope of the present invention.

Embodiments of the present invention provide an SDN-based WLAN hierarchical networking system and method, in which an AC that is in communication with an SDN controller is exchanged as a controller and an SDN controller of an AP connected thereto. On the node, the AC can create a virtual port for the AP and report the status of the virtual port of each AP to the SDN controller, so that the SDN generates management status information. After receiving the management status information, the AC converts the management information of the corresponding AP into CAPWAP. The message is sent to the AP. As the AC acts as both the controller of the AP and the switching node of the SDN controller, the SDN controller, AC, and AP are integrated into a layered WLAN network architecture, which is convenient for the WLAN industry. It is necessary to migrate to SDN. This technology can effectively utilize existing equipment and fully implement various functions in SDN technology, and has good practicability. The specific implementation is as follows:

FIG. 1 is a schematic structural diagram of an SDN-based WLAN hierarchical networking system, where the system includes: an SDN controller 11 and an AC 12 communicatively coupled to the SDN controller 11; wherein, the AP in FIG. 1 is only one example. As shown, in the actual networking, there may be more than one AP connected to the AC.

In the above system, the AC 12 serves as both a controller of the access node AP13 connected thereto and a switching node of the SDN controller 11 itself;

In the above system, because the AC12 acts as the controller of the AP13 connected to it, it can create a virtual port for the AP13, and after the virtual port is successfully created, set the state of the virtual port of each AP13 according to the current network environment; The state of the virtual port of the SDN controller 11 is reported to the SDN controller 11 by the AC 12 .

The SDN controller 11 is configured to receive the status of the virtual port, and then generate management status information according to the received status of the virtual port, and send the management status information to the AC 12;

The AC 12 is further configured to receive the management state information, and the management information of the corresponding AP 13 in the management state information is converted into a CAPWAP (Control and Provisioning of Wireless Access Points Protocol Specification) message and sent to the AP 13.

In this embodiment, the WLAN network (such as the fat AP13 network or the thin AP13+AC12 network) has its own shortcomings, and the SDN network has low networking cost and high network resource utilization due to its hardware standardization. The network planning, design, and management are more flexible. In practice, if the WLAN network that has been built is removed and replaced with SDN, a large amount of funds will need to be reinvested, and the funds originally invested in the WLAN network are also The WLAN-based WLAN hierarchical networking system is configured to enable the WLAN networking to be applied to the SDN, where the WLAN network is migrated to the SDN network. The system effectively utilizes existing equipment and enables existing equipment to have the functions of SDN, thereby saving investors' funds.

The above system uses the original SDN controller 11 (ie, SDN Controller) in the SDN network as the main control component, and the SDN controller 11 is deployed on the cloud server or the high-performance device, and the WLAN network in this embodiment is thin. The networking diagram of AP13+AC12 is used as an example to upgrade the AC12 in the thin AP13+AC12 network. Therefore, when the AC12 does not change its own hardware, it has two functions: 1. It is connected to the AC12. The controller of the AP 13; 2. As a switching node with the SDN controller 11 in the new SDN network. And in this system, thin AP13+AC12 The original AP13 in the networking is unchanged, and the software does not need to be updated. The WLAN controller architecture of the SDN controller 11, AC12, and AP13 is realized, which facilitates the migration of WLAN services to SDN, which not only protects the investment of existing equipment, but also protects the investment of existing equipment. Can make full use of the many benefits brought by SDN technology, which makes the practicality better.

In order to be compatible with the communication protocol of the existing system, in this embodiment, a standard communication protocol OPENFLOW protocol can be used between the SDN controller 11 and the AC 12, wherein the OPENFLOW protocol is a new network switching model; and in order to save costs and simplify the system architecture Designed, AC12 and AP13 are configured and managed through the original CAPWAP protocol.

In the above system, first, the AP 13 successfully accesses the AC 12 through the CAPWAP protocol, and the AC 12 creates a virtual AP port (that is, the virtual port of the AP 13) for accessing the corresponding AP 13 of the AP 13; preferably, the number of the virtual AP ports can be the radio frequency of the AP 13 The number of ports of the device RADIO is determined. When the AP 13 has multiple radio devices RADIO, multiple virtual AP ports are created. After the AC12 creates the virtual port for the AP13, the AC12 sets the state of the virtual port of each AP according to the current network environment, and reports the status of the virtual AP port to the SDN controller 11 through the OPENFLOW protocol, so that the SDN controller 11 is under the SDN controller 11 Send the relevant flow table for configuration.

The radio frequency device (RADIO) of the AP13 can be a radio frequency card.

Specifically, the AC12 creates a virtual port for the AP13, and may have the following implementation manners: if the OF AGENT component is deployed on the AC12, and the AP 13 is virtualized to the local port through the OF AGENT component, so that the SDN controller 11 can configure and manage the AC12 through the standard OPENFLOW interface. AP13 sends the relevant flow table. Specifically, the OF AGENT component is the OPENFLOW agent.

Briefly speaking, for the SDN controller 11, the AP13 and the AC12 are the same device, so the SDN controller 11 can configure and manage the AC12 and the AP13 through the standard OPENFLOW interface; in fact, the AC12 and the AP13 are different, and the AC12 is When all the control information of the SDN controller 11 is received, the control information of the AP 13 is sent to the AP 13 through its own protocol and configuration with the AP 13 . The function of the AC 12 is also to indicate that the AC 12 is connected to it. The controller of the access node AP13 also acts as its own switching node with the SDN controller 11.

As shown in FIG. 3, in order to improve the reliability of the virtual port state, the AC 12 may include: a network environment detecting module 14 configured to detect whether the CAPWAP channel of the current AP 13 is normal, and whether the radio device RADIO of the current AP 13 is in a management working state. The virtual port state setting module 15 is configured to set the state of the virtual port of the current AP 13 to the management working state when the CAPWAP channel of the current AP 13 is normal, and the radio device RADIO of the current AP 13 is in the management working state.

The status of the virtual AP port is determined by the state of the radio device RADIO of the AP13 and the state of the CAPWAP. If only the CAPWAP channel is normal and the radio device RADIO of the AP13 is in the management working state (that is, the UP state), the virtual AP port state. In other cases, the status of the virtual AP port is inactive (that is, the DOWN state). The CAPWAP tunnel is normal, that is, the CAPWAP tunnel is working.

It should be noted that the UP state is the management status of the virtual AP port after power-on, and the virtual AP port is in the non-working state. In this case, the virtual AP port can be powered on or off. status.

In a specific implementation, the foregoing management state information may further include flow table configuration information, and the AC12 may further include: a flow table receiving module, configured to receive flow table configuration information delivered by the SDN controller 11; The processing module is configured to extract the local flow table information from the flow table configuration information, and send the extracted local flow table information to the data plane of the AC 12, and convert the flow table information corresponding to the AP 13 in the flow table configuration information into a wireless connection. The inbound control and configuration protocol CAPWAP message is sent to AP13. In the form of the configuration information of the flow table, the AC can easily distinguish which information belongs to itself and which information belongs to the AP, which simplifies the implementation manner.

Specifically, since the AP 13 is virtualized into a port on the AC 12, the AP 13 is physically invisible to the SDN controller 11 . Therefore, the flow table configuration of the SDN controller 11 to the AP 13 is converted into a common port on the AC 12 . The flow table configuration process realizes the migration of the traditional thin AP13+AC12 network to SDN. The basic flow table configuration process is as follows:

The SDN controller 11 configures the information to the flow table of the AC12 through the OPENFLOW protocol according to the calculation result of the flow table;

AC12 analyzes the configuration information of the flow table from the receiving end, and extracts the flow table information of the local device, and sends the flow table information of the local device to the data plane of the AC12 to support forwarding. Specifically, the AC12 itself is configured. The flow table information is configured by the AC12 according to the flow table information. The AC12 converts the flow table information to the standard CAPWAP message and sends it to the AP13 through the CAPWAP tunnel.

The AP13 maintains entries based on the original CAPWAP process.

As shown in FIG. 2 to FIG. 5, the embodiment of the present invention further provides an SDN-based WLAN hierarchical networking system, which can better realize the migration of the majority of the thin AP+AC architecture network to the SDN, and the basic framework thereof is as shown in FIG. 2, in FIG. 2, the control protocol (ControlPlane) is controlled by the Data Centers, and the communication protocol between the control center and the control platform is the OPENFLOW protocol, wherein The control platform includes: SDN controller, monitor (Application) and application (Application); the OPENFLOW protocol is also used between the control center and the North API.

The data plane (Data Plane, AC) is controlled by the control platform, and the AP is controlled by the data plane, and the communication protocol between the data plane and the AP is the CAPWAP protocol.

Specifically, the SDN controller is deployed as a main control component on a cloud server or a high-performance device. The AC in the original AP+AC network upgrades the software, so that it has two roles at the same time without changing the hardware: the controller AC of the original AP and the switching node in the new SDN network. The original AP remains unchanged, even without updating the software.

For the convenience of the following description, the SDN controller, the AC, and the AP respectively represent the main control component in the SDN network, the AC that performs software upgrade in the original AP+AC networking, and the AP in the AC that is upgraded. The flow table is configured and managed by the standard OPENFLOW protocol between the SDN controller and the AC. The AC and the AP are configured and managed through the original CAPWAP protocol.

Specifically, the entire network channel is as shown in FIG. 3. In the embodiment of the present invention, the OFAGENT component is deployed on the AC to virtualize the AP into a local port of the AC, so that the SDN controller can configure the management AC and the AP through the standard OPENFLOW interface. And issue the relevant flow table.

As shown in Figure 4, the maintenance process of the virtual AP port includes the following steps:

Step S101: The AP successfully accesses the AC through the CAPWAP protocol.

Step S102: Create a virtual AP port for the corresponding AP on the AC.

Specifically, if the AP has multiple RADIOs, multiple virtual AP ports are created.

Step S103: The state of the virtual AP port is determined by the state of the RADIO and the state of the CAPWAP: if and only if the CAPWAP channel is normal and the RADIO on the AP is in the management working state (ie, the UP state), the virtual AP port state is the UP state, and the other In this case, the status of the virtual AP port is inactive (that is, the DOWN state).

Step S104: The AC reports the virtual AP port to the SDN controller through the OPENFLOW protocol.

Step S105, the SDN controller manages the state of the virtual AP port through the OPENFLOW protocol, generates management state information, and sends the management state information to the AC;

Step S106: The AC maps the management status information to the common configuration information, and then sends the information to the AP through the CAPWAP protocol.

As the AP is virtualized into a port on the AC, the AP is physically invisible to the SDN controller. Therefore, the flow table configuration of the SDN controller to the AP is converted into a flow table configuration process for a common port on the AC. The traditional thin AP+AC network migrated to SDN.

The basic flow table configuration process is as follows:

The SDN controller calculates the result according to the flow table, and configures the flow table to the AC through the OPENFLOW protocol.

The AC analyzes the configuration information of the flow table, extracts the flow table information of the local device, and sends the flow table information of the local device to the data plane of the AC to support forwarding. For configuring the flow table information of the AP, the AC converts the flow table information. The standard CAPWAP message is delivered to the AP through the CAPWAP tunnel.

The AP maintains the entries in the original CAPWAP process.

The embodiment of the present invention can easily support the virtual CPE, and the virtual CPE can be uniformly deployed on the SDN controller to access different networks. As shown in FIG. 5, the SDN controller manages the access network and the backup network of the virtual CPE or the virtual access point (VAP) through the AC.

The CPE, that is, the wireless CPE, is a wireless terminal access device that receives a WIFI (WIreless-Fidelity) signal, and can replace a wireless client device such as a wireless network card. It can receive wireless signals from wireless routers, wireless APs, wireless base stations, etc. It is a new type of wireless terminal access device.

In Figure 5, the left side is the access network, and the right side is the backup network.

The embodiment of the invention also supports heterogeneous thin AP+AC hybrid networking. Although traditional WLAN equipment vendors support CAPWAP, they are still not interconnected. After operators purchase equipment from different WLAN equipment vendors, they face the problem of unified management of these devices. After the layered architecture of the present invention is adopted, the heterogeneous thin AP+AC network can be integrated through the SDN controller, and each WLAN device manufacturer can implement the standard SDN interface, which greatly facilitates the heterogeneous thin AP. +AC hybrid networking integration and unified management.

The fat AP networking in the related art stores a large amount of configuration information locally, so that the device loss may cause leakage of configuration information, and it is difficult to collect wireless network state data, and there is a lack of unified management, network maintenance trouble, and software upgrade workload. Dahe has defects such as insufficient support for terminal roaming. The invention also supports the fat AP and the fat AP and the thin AP+AC hybrid networking, and at this time, for the fat AP, the OPENFLOW component needs to be upgraded, and the so-called upgrade OPENFLOW component is actually an OPENFLOW proxy, but this upgrade OPENFLOW component is to implement the AP and The communication of the SDN controller is different from the above OPENFLOW component. Specifically, in the fat AP network, the AP is directly controlled by the SDN controller. Because the fat AP network has no AC, the AC does not need to create a virtual port for the AP. The other implementation process is similar to this embodiment. The AP directly receives configuration and flow table information sent from the SDN controller to guide local forwarding.

The invention provides an SDN-based WLAN hierarchical networking system, which has a simple structure and does not need to modify the existing thin AP+AC network hardware architecture, and only needs to deploy SDN-enabled components on the AC to implement SDN. The hierarchical WLAN network architecture of the controller, AC, and AP is easy to migrate on the SDN of the WLAN service. It not only protects the investment of existing equipment, but also fully utilizes the many benefits brought by SDN technology.

The invention not only provides a solution for migrating the thin AP+AC network to the SDN network, but also effectively supports the integration and unified management of the heterogeneous thin AP+AC network architecture based on SDN, and supports the mixing of the fat AP and the thin AP+AC. Networking is also very convenient.

At the same time, the present invention can fully utilize the strong management function of the AC to the AP, and the QoS (Quality of Service), roaming, and radio frequency resource management WRRM. The implementation of fine management of APs and access users.

As shown in FIG. 6, the embodiment of the present invention further provides a communication method using the foregoing system, where the communication method involves an AC end, and the method includes the following steps:

Step S201: The AC creates a virtual port for the access node AP connected thereto.

In the step S201, the AC is an AC in the thin AP+AC networking. In this embodiment, the AC is first upgraded by software, so as to control the AP connected to the AC without changing the hardware of the AC. The original AP in the thin AP+AC network is unchanged, and there is no need to update the software.

Further, the AC creates a virtual AP port (ie, a virtual port of the AP) for accessing its own AP. Preferably, the number of virtual AP ports can be determined by the number of ports of the radio device (RADIO) of the AP, that is, when the AP When there are multiple radio devices (RADIO), create multiple virtual AP ports. After the AC creates a virtual port for the AP, the AC sets the state of the virtual port of each AP according to the current network environment, and reports the status of the virtual AP port to the SDN controller through the OPENFLOW protocol, so that the SDN controller delivers the relevant status. The flow table is configured.

Specifically, the AC creates a virtual port for the AP, and may have the following implementation manners: if the OF AGENT component is deployed on the AC, and the AP is virtualized to the local port through the OF AGENT component, so that the SDN controller can configure the management AC through the standard OPENFLOW interface. The AP sends the related flow table.

Among them, in order to save costs and simplify the design of the system architecture, the AC and AP are configured and managed through the original CAPWAP protocol.

Step S202: The AC sets the state of the virtual port of each AP according to the current network environment, and reports the state of the virtual port to the SDN controller of the SDN, so that the SDN controller receives the virtual terminal. The status of the port is then generated based on the received status of the virtual port, and the management status information is sent to the AC.

Specifically, in step S202, in the embodiment of the method, the original SDN controller (ie, SDN Controller) in the SDN network is still used as the main control component, and the SDN controller is deployed on the cloud server or the high performance device, and is thin. The AC after the software upgrade of the AC in the AP+AC network can also serve as the switching node of the SDN controller in the new SDN network.

In this embodiment, a standard communication protocol OPENFLOW protocol can be used between the SDN controller and the AC, wherein the OPENFLOW protocol is a new network switching model.

In this embodiment, the management state information generated by the SDN controller includes flow table configuration information.

After receiving the flow table configuration information sent by the SDN controller, the AC extracts the local flow table information from the flow table configuration information, sends the extracted local flow table information to the data plane of the AC, and sends its own flow table information to the corresponding The module performs timely processing, and converts the flow table information of the corresponding AP in the flow table configuration information into a wireless access point control and configuration protocol CAPWAP message and sends the message to the AP, so that the AP performs corresponding processing according to the flow table information.

Step S203: The AC receives the management status information returned by the SDN controller, and converts the management information of the corresponding AP in the management status information into a wireless access point control and configuration protocol CAPWAP message and sends the message to the AP. The management status information is SDN control. Generated based on the state of the virtual port.

To improve the reliability of the virtual port status, the AC also detects whether the current AP's CAPWAP channel is normal, and whether the current AP's RF device is in the working state, and the current AP's CAPWAP channel is normal, and the current AP's RADIO is in management. In the working state, set the state of the virtual port of the current AP to the administrative working state.

An SDN-based WLAN hierarchical networking method is provided by the embodiment of the present invention. The AC can be created for the AP by using the AC that is in communication with the SDN controller as the controller of the AP and the switching node of the SDN controller. The virtual port sends the status of the virtual port of each AP to the SDN controller, so that the SDN generates management status information according to the status of the virtual port of the AP. After receiving the management status information, the AC converts the management information of the corresponding AP into a CAPWAP message. Issued to the AP. Compared with the prior art, the AC is used as a controller of the AP and as a switching node of the SDN controller, and implements a hierarchical WLAN network architecture of the SDN controller, the AC, and the AP, facilitating the WLAN service to the SDN. Migration can not only effectively utilize existing equipment, but also fully implement various functions in SDN technology, and has good practicability.

As shown in FIG. 7, the embodiment of the present invention further provides a communication method using the foregoing system, where the communication method relates to an SDN controller, and includes the following steps:

In step S301, the SDN controller of the SDN receives the status of the virtual port reported by the access controller AC. The virtual port is created by the AC for each access node AP connected thereto. The status of the virtual port is AC according to the current network environment. Set.

In this embodiment, the original SDN controller (ie, SDNController) in the SDN network is also used as the main control component, and the SDN controller is deployed on the cloud server or the high-performance device, and the AC in the thin AP+AC network is performed. After the software is upgraded, the AC acts as both the controller of the access node AP connected to it and the switching node of the SDN controller in the new SDN network.

Because the AC acts as the controller of the AP connected to it, it can create a virtual port for the AP. After the virtual port is created successfully, set the state of the virtual port of each AP according to the current network environment. Because the AC also controls itself as the SDN. The switching node of the device, so the AC reports the status of the virtual port it created to the SDN controller.

In this embodiment, a standard communication protocol OPENFLOW protocol can be used between the SDN controller and the AC, wherein the OPENFLOW protocol is a new network switching model, and in order to save cost and simplify the design of the system architecture, the AC and the AP pass the original The CAPWAP protocol is configured and managed.

Step S302: The SDN controller generates management state information according to the state of the virtual port, and sends the management state information to the AC, so that the AC converts the management information of the corresponding AP in the management state information into a wireless access point control and configuration protocol CAPWAP message. Send to AP.

In the above steps, the management state information is the flow table configuration information, and the SDN controller calculates the result according to the flow table (that is, the flow table configuration information), and configures the flow table configuration information to the AC through the OPENFLOW protocol, so that the AC analyzes the flow from the receiving end. Table configuration information, and extracts the flow table information of the local device, and sends the flow table information of the local device to the data plane of the AC to support forwarding.

Specifically, for configuring the flow table information of the AC itself, the AC directly configures the flow table information; for configuring the flow table information of the AP, the AC converts the information into a standard CAPWAP message, and delivers the information to the AP through the CAPWAP tunnel, so that the AP can The original CAPWAP process maintenance table.

An SDN-based WLAN hierarchical networking method provided by an embodiment of the present invention, by using an AC that is in communication with an SDN controller as a controller of an AP connected thereto and also as a switching node of an SDN controller, The AP creates a virtual port and reports the status of the virtual port of each AP to the SDN controller. The SDN receives the status of the virtual port of the AP, and generates management status information according to the status of the virtual port of the AP and sends the status information to the AC for AC reception. After the management status information is obtained, the management information of the corresponding AP is converted into a CAPWAP message and sent to the AP. Compared with the prior art, the AC is used as both the controller of the AP and the switching node of the SDN controller. The hierarchical WLAN network architecture of the SDN controller, the AC, and the AP is realized, which facilitates the migration of the WLAN service to the SDN, and can effectively utilize the existing equipment and fully implement various functions in the SDN technology, and has good practicability.

The above is only a specific embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily think of changes or substitutions within the technical scope of the present invention. It should be covered by the scope of the present invention. Therefore, the scope of the invention should be determined by the scope of the claims.

Claims

A WLAN hierarchical networking system based on a software-defined network SDN, comprising: an SDN controller and an access controller AC communicatively coupled to the SDN controller, the AC being connected thereto Accessing the controller of the node AP and also acting as a switching node of the SDN controller;

The AC creates a virtual port for the AP, and the AC is configured to set the state of the virtual port of each AP according to the current network environment, and report the state of the virtual port to the SDN controller.

The SDN controller is configured to receive the status of the virtual port, generate management status information according to the status of the virtual port, and send the management status information to the AC;

The AC is further configured to receive the management state information, and convert the management information corresponding to the AP in the management state information into a wireless access point control and configuration protocol CAPWAP message and send the message to the AP.
The system of claim 1 wherein said AC comprises:

The network environment detecting module is configured to detect whether the CAPWAP channel of the current AP is normal, and whether the radio equipment of the current AP is in a management working state;

The virtual port state setting module is configured to set the state of the virtual port of the current AP to a management working state when the CAPWAP channel of the current AP is normal, and the radio device of the current AP is in a management working state.
The system according to claim 1, wherein the management status information comprises: flow table configuration information;

The AC includes:

a flow table receiving module, configured to receive flow table configuration information delivered by the SDN controller;

a flow table processing module, configured to extract the local flow table information from the flow table configuration information, and send the extracted local flow table information to the data plane of the AC, and the corresponding information in the flow table configuration information The flow table information of the AP is converted into a wireless access point control and configuration protocol CAPWAP message and sent to the AP.
The system according to any one of claims 1 to 3, characterized in that the communication protocol adopted between the SDN controller and the AC is the OPENFLOW protocol.
A communication method for applying the system according to any one of claims 1 to 4, characterized in that it comprises:

The access controller AC creates a virtual port for the access node AP connected thereto;

The AC sets the state of the virtual port of each AP according to the current network environment, and reports the state of the virtual port to the SDN controller of the software-defined network SDN.

Receiving, by the AC, the management status information returned by the SDN controller, and converting the management information corresponding to the AP in the management status information into a wireless access point control and configuration protocol CAPWAP message, and sending the information to the AP; The management status information is generated by the SDN controller according to the status of the virtual port.
The method according to claim 5, wherein the setting, by the AC, the status of the virtual port of each of the APs according to the current network environment includes:

The AC detects whether the CAPWAP channel of the current AP is normal, and whether the radio equipment of the current AP is in a management working state;

When the CAPWAP channel of the current AP is normal, and the radio device of the current AP is in a working state, the AC sets the state of the virtual port of the current AP to a management working state.
The method according to claim 5, wherein the management status information comprises: flow table configuration information;

The AC converts the management information corresponding to the AP in the management state information into a wireless access point control and configuration protocol, and the CAPWAP message is sent to the AP, where the AC receives the flow delivered by the SDN controller. The table configuration information: the AC extracts the local flow table information from the flow table configuration information, and sends the extracted local flow table information to the data plane of the AC, where the corresponding information in the flow table configuration information is The flow table information of the AP is converted into a wireless access point control and configuration protocol CAPWAP message and sent to the AP.
The method according to any one of claims 5-7, characterized in that the communication protocol adopted between the SDN controller and the AC is the OPENFLOW protocol.
A communication method for applying the system according to any one of claims 1 to 4, characterized in that it comprises:

The SDN controller of the software-defined network SDN receives the status of the virtual port reported by the access controller AC; wherein the virtual port is created by the AC as each access node AP connected thereto, and the status of the virtual port is The AC is set according to a current network environment;

The SDN controller generates management state information according to the state of the virtual port, and sends the management state information to the AC, so that the AC associates the management state information with the corresponding The management information of the AP is converted into a wireless access point control and configuration protocol CAPWAP message and sent to the AP.
The method according to claim 9, wherein a communication protocol adopted between the SDN controller and the AC is an OPENFLOW protocol.