KR20090088754A - Method for operating access control router of wireless communication system and wireless communication system applying that method - Google Patents

Abstract

An access control router operating method in a wireless communication system and the wireless communication system adopting the same are provided to disperse the load, which is generated due to the increase in the number of terminals or service use, to access control routers within a cluster, efficiently by clustering the access control routers. A controller access control router selects one of member access control routers for the service flow processing within an access control router cluster consisting of one controller access control router and one or more member access control routers(S510). In case a member access control router is selected, the controller access control router transmits a notification for access control router selection, including context information of a terminal which corresponds to the service flow, to the selected member access control router(S540).

Description

Method for Operating Access Control Router of Wireless Communication System and Wireless Communication System Applying That Method}

The present invention relates to a wireless communication system, and more particularly, to a method of operating a control station in a wireless communication system and a wireless communication system to which the method is applied.

Recently, in-depth research is being carried out in various layers to realize 4G mobile communication. In the 4th generation mobile communication according to IEEE 802.16d / e, WiBro, WiMAX standard, etc., not only satellite network but also wireless LAN network, digital audio broadcasting and video broadcasting network are integrated into one single network which is organically interworked. You will receive smooth communication services in the best possible condition.

In a system for providing such a wireless communication service, mobile stations (MSs) receive communication from radio access stations (RAS) and base stations (BSs) to provide communication services such as call, digital broadcasting, digital media download, and upload. I can receive it. The base station is connected to each other based on an access control router (ACR) and an Ethernet, and an IP (Internet Protocol) packet routed under the control of the control station is transmitted and received to or from a destination terminal or a destination server through an associated base station. .

At this time, the base station processes a bridging role for fast connection with the terminal, scheduling of radio resources, and a radio frequency (RF) control function, and the control station is mainly responsible for an L3 (Layer 3: Layer 3) function. Terminating Point (Terminating Point) is configured to route the terminal and the base station so as to properly transmit and receive IP packets. The control station may support the authentication and the charging function by interworking with the AAA (Authentication / Authority / Accounting: Authentication, Authorization, Accounting) server.

However, in the case of a wireless communication network such as a general WiBro network, as the number of terminals or service usage increases, the signaling traffic load due to authentication and billing processing of these terminals may be relatively increased. If the network is continuously weighted, there is a problem that the capacity or performance of the entire access network may be reduced, which may cause data loss or delay, and as a result, it may be difficult to provide reliable and stable services to customers.

In order to solve this problem, it is possible to consider a high-performance control station that can replace the existing control station or a control station that can smoothly provide communication service for a large number of terminals. In addition to the cost burden, there is a problem in that all configurations on the communication system must be changed to replace the existing control station on the communication system.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problem, and a method of operating a control station in a wireless communication system capable of efficiently distributing a load increased according to the number of terminals or service usage by clustering a plurality of control stations and It is a technical problem to provide a wireless communication system to which the method is applied.

 Another object of the present invention is to provide a method for operating a control station in a wireless communication system capable of stably providing a wireless communication service by duplexing each control station, and a wireless communication system to which the method is applied.

In addition, the present invention provides a method for operating a control station in a wireless communication system capable of distributing a control plane function and a data plane function for one service flow processing to control stations included in a control station cluster, and a radio to which the method is applied. It is another technical problem to provide a communication system.

A control station operating method in a wireless communication system according to an aspect of the present invention for achieving the above object is in a control station cluster consisting of one controller control station (Access Control Router) and at least one member control station (Cluster) The controller control station selecting one of itself or the member control station as a control station for processing a service flow; When the member control station is selected, sending, by the controller control station, a control station selection notification including context information of a terminal corresponding to the service flow to the selected member control station; And processing, by the selected member control station, the service flow using the context information included in the control station selection notification.

A control station operating method in a wireless communication system according to another aspect of the present invention for achieving the above object is in a control station cluster consisting of one controller control station (Access Control Router) and at least one member control station Performing, by the controller control station, a control plane function for service flow; Selecting, by the controller control station, a control station to perform a data plane function for processing the service flow among the member control stations; Sending, by the controller control station, a control station selection notification including context information of a terminal corresponding to the service flow to the selected member control station; And performing, by the selected member control station, the data plane function for the service flow processing using the context information included in the control station selection notification.

A wireless communication system according to another aspect of the present invention for achieving the above object selects a control station for service flow processing in a control station cluster generated by clustering a plurality of control stations A controller control station for transmitting a control station selection notification including context information of the terminal corresponding to the service flow to the selected control station; And one or more member control stations that process the service flow using the context information included in the control station selection notification when the control station selection notification is received from the controller control station.

A wireless communication system according to still another aspect of the present invention for achieving the above object performs a control plane function for processing a service flow and other than itself in a control station cluster generated by clustering a plurality of control stations. A controller control station selecting a control station as a control station to perform a data plane function for processing the service flow, and transmitting a control station selection notification including context information of a terminal corresponding to the service flow to the selected control station; And at least one member control station performing a data plane function for processing the service flow by using the context information included in the control station selection notification when the control station selection notification is received from the controller control station. .

According to still another aspect of the present invention for achieving the above object, a wireless communication system includes at least one control station cluster for controlling terminals and base stations in a service area and processing a service flow. Clustering a controller control station and at least one member control station, wherein the controller control station performs a control plane function for the service flow and selects a member control station to perform a data plane function for the service flow; And transmitting context information of a terminal corresponding to the service flow to the selected member control station so that the selected member control station performs a data plane function for the service flow.

As described above, according to the present invention, by clustering a plurality of control stations, the load generated as the number of terminals or service usage increases can be efficiently distributed to each control station included in the cluster, thereby improving system performance. In addition, subscriber capacity can be increased.

In addition, the present invention can handle the increased load by clustering the existing control station without adding additional equipment or configuration changes on the system, there is an effect that the increase in economic burden can be minimized.

In addition, the present invention has the effect that it is possible to improve the reliability of the wireless communication service by stably providing the wireless communication service by duplexing the respective control stations.

In addition, the present invention can distribute the control plane function and data plane function for one service flow processing to the control stations included in the control station cluster, thereby improving the robustness of the wireless communication system.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a schematic block diagram of a wireless communication system according to an embodiment of the present invention. In the wireless communication system according to the present invention, as shown, a mobile station (100), a base station (Radio Access Station, Base Station, 110), a core network (Core Network, 120), AAA (Authentication / Authority / Accounting) A server 130, an HA (Home Agent 140), and an access control router cluster 150 in which a plurality of control stations are clustered.

In one embodiment, such a wireless communication system may be applied to the IEEE802.16d / e, Wibro, WiMAX standard specification.

On the other hand, the wireless communication system according to the present invention, in addition to the components shown in Figure 1, the quality manager (Quality Manager) for controlling the call session quality, the location register (Location Register) for managing the location and state of the terminal, the multimedia service Other components, such as providing an application server may be further included.

As can also be seen in Figure 1, the wireless communication system according to the present invention, in order to increase the capacity of the system by distributing the load (load) generated in one control station to a plurality of control stations, Clustering forms one control station cluster, which causes the control station cluster to act as one control station.

In FIG. 1, the terminal 100 receives various relays of the base stations and provides various services such as voice call, digital broadcasting, digital media download / upload, etc. to the user. In case of access, the RRC (Radio Resource Control) function according to the radio resource scheduling and the handoff (Handoff) function to support the mobility between cells to perform the communication between the terminals.

The AAA server 130 is connected to the control stations 152 to 158 through the core network 120 to process authentication, authorization verification, and charging of the terminal 100, and the HA 140 is the core network 120. It is connected to mobile IP registration allocation and data encapsulation function.

The control station cluster 150 is a cluster of a plurality of control stations (152 ~ 158), such a control station cluster 150 is composed of one controller control station 152 and one or more member control stations (154 ~ 158) It is composed.

First, the controller control station 152 is a control station for selecting a control station to process the service flow of each terminal 100 in the control station cluster 150 to which it belongs, in one embodiment the controller The control station 152 can select itself as well as the member control stations 154 to 158 as the control station for the service flow processing.

When the controller control station 152 selects itself as the control station for the service flow processing, the controller control station 152 processes all transactions for the service flow processing. On the other hand, when selecting the member control stations 154 to 158 as the control station for the service flow processing, the controller control station 152 processes only some of the transactions for the service flow processing, and processes the remaining transactions to the selected member control station. The control station selection notification is sent to the selected member control stations 154-158 for processing.

On the other hand, when the member control stations 152 to 158 are selected as the control stations to process the newly requested service flow, the member control stations 152 to 158 newly perform by performing a control plane function and a data plane function for the corresponding service flow. Process the requested service flow.

The detailed configuration of such a controller control station 152 and member control stations 154 to 158 is shown in FIG. As shown, the controller control station 152 and the member control stations 154 to 158 are the load balancing units 200 and 230, the control plane function performing units 210 and 240, and the data plane function performing unit 222, respectively. , 252).

First, referring to the configuration of the controller control station 152, the load balancing unit 200 calculates the load of the controller control station 152, and processes the service flow in the control station cluster 150 in accordance with the calculated load Select the control station to be used. In one embodiment, the load balancing unit 200 may be configured by using at least one of the ratio of the maximum number of sessions that the controller control station 152 can support to the number of current sessions, memory usage, and bandwidth usage of the control station. The load can be calculated.

When the load balancing unit 200 selects a control station to process a service flow in the control station cluster 150, when the calculated load is greater than or equal to a threshold, any one of the member control stations 154 to 158 performs a service flow. As the control station to process, and if the calculated load is below the threshold, the controller control station 152 can be selected as the control station to process the service flow.

When the load balancing unit 200 selects the member control stations 154 to 158 for service flow processing, the load balancing unit 200 transmits the member control stations 154 to 158 to the selected member control stations 154 to 158. Transmits a control station selection notification to inform that it is a control station selected for service flow processing. The selection notification includes context information of the terminal corresponding to the corresponding service flow generated by the control plane function performing unit 210 to be described later.

According to an embodiment, the load balancing unit 200 controls a member to process a service flow using a round robin method among the plurality of member control stations 154 to 158 included in the control station cluster 150. The member control stations 154 to 158 that select the stations 154 to 158 or have the least load of the member control stations 154 to 158 reported from the member control stations 154 to 158 to process the service flow. The member control stations 154 to 158 can be selected. To this end, the load balancing unit 200 reports the load of each member control station 154 to 158 from each member control station 154 to 158 whenever a predetermined condition is satisfied, or each member control station 154 to 158. It is possible to request the load of each member control station 154 to 158.

When the load balancing unit 200 selects the member control stations 154 to 158 with the smallest load as the control station to process the service flow, or when selecting the first member control station to process the service flow or all member control stations. When the loads of (154 to 158) are the same, the member control station to process the service flow can be selected using the round robin method or a random method.

Further, in selecting the member control station, the load balancer 200 selects a member control station 154 to process a service flow based on the load of the controller control station 152 or the load of each member control station 154 to 158. 158) can be adjusted. That is, one member control station may be selected according to the load of the controller control station 152 or the load of each member control station 154 to 158, but one or more member control stations may be selected.

Meanwhile, when the load balancing unit 200 selects the member control stations 154 ˜ 158 for service flow processing, the load balancing unit 200 does not need to perform a transaction for processing the corresponding service flow in the controller control station 152. In addition, the control plane function performing unit 210 to be described later notifies the end of the transaction for the service flow processing.

The control plane function performing unit 210 performs a control plane function for service flow processing, and includes an authentication unit 211, a charging processing unit 212, an AAA interface 213, a DHCP 214, and a handoff processing unit 215. ), A service flow unit 216, a location registration unit 217, a paging unit 218, a PMIP unit 219, and a quality control unit 220.

In the present invention, functions of the other components except for the authentication unit 211 is the same as the functions of the respective components included in the general control station will be described below focusing on the function of the authentication unit 211, authentication unit 211 The functions of the components except for) will be briefly described.

The authentication unit 211 authenticates / processes the service flow request. When there is a new service flow request from the base station 110, the authentication unit 211 transmits a predetermined authentication algorithm, for example, EAP (EAP), to the AAA server 130 connected to the core network 120. Request for authentication according to an Extensible Authentication Protocol) method, and transmits the result to the base station 110.

In particular, the authentication unit 211 according to the present invention generates the context information for the terminal 100 corresponding to the newly requested service flow and transmits it to the load balancer 200 described above, and the load balancer 200 When the controller selects the controller control station 152 as the control station to process the service flow, the authentication procedure for the service flow is performed according to a general procedure for processing the service flow.

When the load balancing unit 200 selects the member control stations 154 to 158 as the control station to process the corresponding service flow, the authentication unit 211 may provide information of the selected control station, for example, the authentication unit of the selected control station. After transmitting the ID to the base station 110, and receives the end notification of the transaction for the processing of the service flow from the load balancer 200, the terminal corresponding to the service flow after ending the transaction for the processing of the service flow The context information of 100 is deleted.

When the charging processing unit 212 receives a predetermined charging processing message from the base station 110, the charging processing unit 212 requests the charging according to the corresponding service to the AAA server 130 connected to the core network 120, and the AAA interface 213 receives the authentication unit ( 211) and the billing processing unit 212 to play a message to the AAA server 130, so as to mediate the authentication unit 211 and the billing processing unit 212 with the AAA server 130.

The DHCP 214 performs an IP address allocation function according to the DHCP, and the handoff processing unit 215 is configured to transmit a handoff request transmitted when a handoff occurs due to the movement between the cell / control station of the terminal 100. Manage the information necessary for session management and routing so that session configuration can be maintained without interruption.

The service flow unit 216 may include an unsolicited grant service (UGS), a real time polling service (RTT-PS), an extended real time polling service (ERT-PS), and an Nrt-PS (TFT) according to the traffic type from the terminal 100. Scheduling services such as Non-Real Time Polling Service (BES) and Best Effort Service (BES) are supported.

The location register 217 registers the location of the currently connected terminal 100, and the paging unit 218 determines the location of the base station 110 when an incoming call is generated from the currently connected terminal 100. The function, the PMIP unit 219 supports the IP mobility of the terminal 100, the quality control unit 220 controls the communication quality currently serviced to maintain the best service suitable for the predetermined traffic.

The data plane function performing unit 222 selects the controller control station 152 as the control station to which the above-described load balancing unit 200 processes the service flow, and performs the service flow processing by the control plane function performing unit 210. When the control plane function is completed, the data plane function for service flow processing is performed, and includes a data path processing unit 224, a FA 226, a routing unit 228, and a management unit 229.

The data path processor 224 stores and manages the data transmitted and received from the terminal 100 or the core network 120 so that the data can be accurately transmitted to the destination without loss. The FA 226 detunnels data transmitted from the HA 140 through tunneling, and transmits data related to the registered UE 100.

The routing unit 228 performs a routing function by a routing protocol so that data received by the control control station 152 can be transmitted toward a destination, and the management unit 229 is configured, initialized, and operated for operation of the control station. Perform administrative and statistical functions.

Next, the configuration of the member control stations 154 to 158 will be described. When the load balancing unit 230 calculates the load of the member control stations 154 to 158 to become a predetermined period, the calculated load is greater than or equal to the threshold value. In this case, or when either of the requests from the controller control station 152 occurs, the calculated load is transmitted to the load balancing unit 200 of the controller control station 152.

In one embodiment, the load balancing unit 230 may calculate the load of the control station using at least one of the maximum number of sessions that the control station can support, the ratio of the number of current sessions, memory usage, and bandwidth usage. have. At this time, each member control station (154 to 158) can calculate the load of the member control station by using the memory usage or bandwidth usage while the service flow is not processing, and while processing the service flow of each member control station (154 ~ 158) You can calculate the load using the ratio of the number to the number of current sessions.

In addition, the load balancing unit 230 receives a control station selection notification including context information of the terminal corresponding to the service flow to be processed from the controller control station 152, and processes the service flow to the authentication unit 241 to be described later. Notifies the start of a transaction for a.

When the selection notification is received by the load balancer 230, the control plane function performing unit 240 performs a control plane function for processing the corresponding service flow. The control plane function performing unit 240 includes the same components as those included in the control plane function performing unit 210 of the controller control station 152 described above. Except for the functions of the authentication unit 241 among the components 241 to 250, all of the components included in the control plane function performing unit 210 of the controller control station 152 are the same. Only the functions will be described.

When the control unit selection notification is received by the load balancing unit 230, the authentication unit 241 generates new context information for the corresponding terminal by using the context information of the terminal included in the control station selection notification, and newly generated context. Authenticate the service flow requested for processing using the information.

That is, when the controller control station 152 is selected as the control station to process the service flow, the AAA server 130 connected to the core network 120, the authentication according to a predetermined authentication algorithm, for example, EAP (Extensible Authentication Protocol) method To request and transmit the result to the base station 110.

When the data plane function performing unit 252 receives the selection notification by the load balancing unit 230 and the control plane function performing unit 240 completes the control plane function, the data plane function for processing the corresponding service flow is performed. Since the functions and components 254 to 260 are the same as the functions and components of the data plane function performing unit 222 of the controller control station 152 described above, a detailed description thereof will be omitted.

In the above-described embodiment, it has been described that each of the controller control station 152 and the member control stations 154 to 158 can perform both the control plane function and the data plane function. However, in the modified embodiment, the control control station ( 152 may be designed to perform only the control plane function, and member control stations 154 to 158 may perform only the data plane function.

According to such an embodiment, since the controller control station 152 only needs to perform a control plane function, it may not include a data plane function performing unit, and the member control stations 154 to 158 need only perform a data plane function. It may not include the control plane function implementation.

The configuration of the controller control station 152 and the member control stations 154 to 158 according to this embodiment will be described in more detail with reference to FIG. 3.

As shown, the controller control station 152 includes a load balancing unit 300 and a control plane function performing unit 310.

The load balancing unit 300 selects the member control stations 154 to 158 to perform the data plane function for processing the newly requested service flow. In one embodiment, the load balancing unit 300 may include a control station cluster ( Among the plurality of member control stations 154 to 158 included in the 150, the member control stations 154 to 158 are selected by using a round robin method or reported from each member control station 154 to 158. It is possible to select the member control stations 154 to 158 with the smallest loads of the respective member control stations 154 to 158. To this end, the load balancing unit 300 reports the load of each member control station 154 to 158 from each member control station 154 to 158 whenever a predetermined condition is satisfied, or each member control station 154 to 158. Request to load each member control station (154 to 158).

When any one of the member control stations 154 to 158 is selected through the above-described method, the load balancing unit 300 processes the service flow by the member control station 154 to 158 to the selected member control station 154 to 158. Send a control station selection notification to indicate that it is the control station selected for. The control station selection notification includes context information of the terminal corresponding to the corresponding service flow generated by the control plane function performing unit 310 to be described later.

The control plane function performing unit 310 performs a control plane function for service flow processing, and includes an authentication unit 312, a charging processing unit 314, an AAA interface 316, a DHCP 318, and a handoff processing unit ( 320, a service flow unit 322, a location registration unit 324, a paging unit 326, a PMIP unit 328, and a quality control unit 330. In the case of the control plane function performing unit 310 shown in FIG. 3, the function of the control plane function performing unit in the case where the controller control station 152 is selected as the control station to process the service flow in the embodiment shown in FIG. And since the components are the same, a detailed description will be omitted.

The member control stations 154 to 158 may include a load balancer 340 and a data plane function performer 350.

The load balancing unit 340 calculates the loads of the member control stations 154 to 158 to become a predetermined period, when the calculated load is greater than or equal to a threshold, or when there is a request from the controller control station 152. When either occurs, the calculated load is transmitted to the load balancing unit 300 of the controller control station 152. In one embodiment, the load balancing unit 340 calculates the load of the control station by using at least one of the maximum number of sessions that the control station can support, the ratio of the number of current sessions, memory usage, and bandwidth usage. Can be.

In addition, the load balancing unit 340 receives the control station selection notification including the context information of the terminal corresponding to the service flow to be processed from the controller control station 152, corresponding to the data plane function performing unit 350 to be described later Notifies the execution of the data plane function for service flow processing.

When the data plane function execution unit 350 receives a data plane function execution notification from the load balancer 340, the data plane function execution unit 350 performs a data plane function for processing the corresponding service flow, and functions of the data plane function execution unit 350. Since the components 352 to 358 are the same as the data plane function performing unit 252 of the member control stations 154 to 158 shown in FIG. 2, a detailed description thereof will be omitted.

In the above-described embodiment, the controller control station 152 is described as including only the control plane function performing unit. In the modified embodiment, the controller control station 152 is used to improve the performance and expand the capacity of the wireless communication system. ) May be designed to perform both control plane and data plane functions. Thus, in this case, the controller control station 152 will include both a control plane function performer and a data plane function performer.

In addition, in the above-described embodiment, the member control station is described as operated when the controller control station is selected as the control station to process a specific service flow. However, in the modified embodiment, the member control station is selected by the controller control station. Even if it is not selected as the control station to process the service flow, it may be able to directly process the service flow of the base stations except base stations managed by the controller control station for efficient system operation.

For example, when the controller control station 152 is in charge of the first to third base stations 110, the member control stations 154 to 158 in the case of the service flow requested from the first to third base stations 110 When selected by the controller control station 152, the corresponding service flow is processed, but in the case of a service flow requested from another base station (not shown) except for the first to third base stations 110, the user may process the service directly. Could be.

In another embodiment, when there are a plurality of control station clusters 150, control stations belonging to one control station cluster may be included in other control station clusters. In this case, what was a member control station in one control station cluster may be a controller control station in another control station cluster, and on the contrary, what was a controller control station in a control station cluster may be a member control station in another control station cluster. There will be.

As shown in FIG. 4, control stations of a wireless communication system according to another embodiment of the present invention may be duplicated to prevent service interruption while providing WiMAX services. To this end, each control station is designed in a 1 + 1 structure consisting of the active (400) and standby (Standby) equipment (460). That is, the controller control station is composed of an active control station and a standby control station, and the member control station is also composed of an active control station and a standby control station.

The redundancy request is largely caused by the recognition of the standby device, by the operator setting, by the error of the critical application, by the error of the critical hardware, and so on. The information to be redundant includes configuration information, address resolution protocol (ARP) information, routing information, routing protocol information, and WiMAX information set by an operator.

The redundancy of ARP information is to ensure that the standby equipment does not interrupt service by immediately using the ARP information of the active device when an abnormality of the active device is detected, and the duplication of routing information is detected by the abnormality of the active device. When the standby device, the standby device immediately uses the routing information of the active device so that there is no interruption of service.

In addition, the duplication of the routing protocol information is to ensure that there is no interruption of service using the routing protocol information of the active device immediately when an abnormality is detected for the active device. Protocols that must support redundancy include Routing Information Protocol (RIP), Open Shortest Path First (OSPF), Border Gateway Protocol (BGP), and Intermediate System ­ Intermediate System (ISI).

The redundancy of the WiMAX information is to ensure that the standby device immediately uses the active device's WiMAX session information when there is a problem with the active device so that there is no interruption of service. Here, the WiMAX session information includes subscriber data path, billing and authentication, and IP configuration information.

The control station of the wireless communication system according to an embodiment of the present invention for implementing the above-described control station redundancy sets the active device 400 and the standby device 460 to an active state and a standby state, respectively, to activate the active device 400. ) And all the above-mentioned redundancy information in the standby device 460 are set identically. At this time, an exception is that a communication interface for internal redundancy is operated with different IPs.

The control station of the wireless communication system according to another embodiment of the present invention for implementing the above-described control station redundancy activates both the active device 400 and the standby device 460 to reduce the number of elements to be duplicated. Configure to state. Specifically, only the WiMAX redundancy elements of the above-described redundancy elements in the active device 400 and the standby device 460 are kept to be the same.

An active device and a standby device in the case of following this embodiment will be described in detail with reference to FIG. 4. As shown, the active device 400 includes a first initialization unit 420, a first control unit 430, a first redundancy unit 440, and a first state transition unit 450.

The first initialization unit 420 sets a physical interface IP, a logical interface IP, and a dynamic routing protocol, and includes a first interface setting unit 422 and a first routing protocol setting unit 424.

The first interface setting unit 422 sets the standby device 460 and the physical interface IP differently, and sets the logical interface IP the same. The first interface setting unit 422 maintains the logical interface in an inactive state until the active / standby state is determined.

When WiMAX communication is performed through a physical interface that is a direct resource of the system, the interface IP of the active device 400 and the interface IP of the standby device 460 must be the same for communication with the base station and the HA interworking with the control station. Therefore, to overcome the problem that the external interface IP must be the same, a logical interface is used to perform the WiMAX control plane / data plane functions.

These logical interfaces are used as GRE endpoints and signaling endpoints for interworking with WiMAX R6 base stations, and as IPinIP / GRE endpoints and signaling endpoints for interfacing with WiMAX R3 compliant HA. It is also used as a GRE end point and a signaling end point for interworking with a control station of the WiMAX R4 standard.

The first routing protocol setting unit 424 sets a predetermined dynamic routing protocol in the active device 400, and when an abnormality is detected in the active device 400, the standby device 460 immediately uses a routing protocol that is set up. By providing a service, there is no interruption of service. Both the active device 400 and the standby device 460 perform activation setup using dynamic routing protocols (eg, RIP, OSPF, BGP, ISIS) for WiMAX service. In addition, the logical interface created for the WiMAX service is also included in the routing domain to prepare for smooth communication with the base station 110 and the HA 140. At this time, the interface set for internal redundancy is kept inactive so that the interface information is not included in the routing domain initially.

The first controller 430 sets the active device 400 to an active state by using the internal communication interface of the active device 400, the active device 400 to be active, and the standby device 460 to be in a standby state. When enabled, the logical interface of the active device 400 may be activated to provide WiMAX service. The activation of this logical interface causes logical interface information to be included in the routing domain. At this time, the corresponding logical interface of the standby device 460 continues to be inactive.

As described above, the WiMAX control plane function and the data plane function are performed only through the active device 400 based on the information set by the first initialization unit 420 and the first control unit 430.

The first duplication unit 440 duplicates configuration information and WiMAX information of the active device 400. The redundancy of the configuration information is to make the WiMAX operation state the same so that the operator's WiMAX related setting information is reflected in the standby device 460 in the active device 400.

The duplication of WiMAX information is performed when the subscriber information is added or deleted according to the operation of the WiMAX session to the active device 400. The subscriber information, for example, data path, billing and authentication, and IP configuration information, is stored in the standby device 460. To be added or deleted in the same way.

When the state transition event of the active device 400 occurs, the first state transition unit 450 is configured in the logical interface and the first redundancy unit 440 activated by the first control unit 430 based on the set interface and the dynamic routing protocol. A state transition of the active device is performed by using the redundant information, and includes a first interface processor 452, a first information manager 454, and a first redundant information receiver 456.

The first interface processor 452 releases and deactivates the logical interface of the active device in the routing domain. Specifically, the deactivation information is propagated to the routing protocol in operation in order to release the routing information of the previously registered logical interface in the routing domain. All the devices in the routing domain that receives this will delete the information received from the active device (400). Then, by changing the interface state of the active device 400 to the inactive state to prevent receiving the WiMAX service.

The first information manager 454 deletes the WiMAX information of the active device 450 and maintains the same information as the standby device 460.

The first redundancy information receiver 456 waits for receiving redundancy information, that is, configuration information and WiMAX information from the existing standby device 460 converted to the active device, and receives the redundancy information.

Meanwhile, the standby device 460 includes a second initialization unit 470, a second control unit 480, a second redundancy unit 490, and a second state transition unit 500.

The second initialization unit 470 sets the physical interface IP, the logical interface IP, and the dynamic routing protocol, and includes a second interface setting unit 472 and a second routing protocol setting unit 474.

The second interface setting unit 472 sets the IPs of the active device 400 and the physical interface differently, and sets the logical interface IPs the same. At this time, the logical interface is maintained in an inactive state until it is determined as an active state or a standby state.

The second routing protocol setting unit 474 sets the dynamic routing protocol to the standby device. The standby device 460 performs activation setup using a dynamic routing protocol for the WiMAX service. The logical interface created for the WiMAX service is also included in the routing domain to prepare for smooth communication with the base station and the HA. At this time, the interface set for internal redundancy is kept inactive so that the interface information is not included in the routing domain initially.

The second controller 480 determines the standby state by using the internal communication interface of the standby device 460, and maintains the logical interface of the standby device 460 in an inactive state.

The second duplication unit 490 duplicates configuration information and WiMAX information of the active device. This is to equalize the WiMAX operation state by reflecting the WiMAX-related setting information set by the operator in the active device 400 in the standby device 460 in the same manner. In addition, when the subscriber information according to the WiMAX session operation is added to or deleted from the active device 400, the corresponding subscriber information is added or deleted to the standby device 460 in the same manner.

When the state transition event of the standby device 460 occurs, the second state transition unit 500 activates a logical interface deactivated in the second control unit 480 based on the set interface information and the dynamic routing protocol, and second redundancy. By performing the state transition of the standby equipment 460 by using the redundancy information performed in the unit 490, the second interface processing unit 502, the second information management unit 504 and the second redundancy information receiving unit 506 Include.

When the second interface processing unit 502 receives an event that the standby device 460 needs to transition to an active state, the second interface processing unit 502 activates a logical interface in an inactive state of the standby device 460, and all the devices in the routing domain become standby devices ( In step 460, the logical interface is registered in the routing domain with a metric value smaller than that of the metric previously advertised in the existing active device 400. The second information manager 504 activates WiMAX-related information received from the active device 400 so that the WiMAX service can proceed without interruption. When the second redundant information receiver 506 is switched from the standby device 460 to the active device 400, the second redundant information receiver 506 waits to receive the redundant information, that is, the configuration information and the WiMAX information.

As such, by duplexing the control station, the WiMAX service can be normally provided even if a failure occurs in the control station. In particular, when both the active device and the standby device are set as the active device, routing information and routing are performed. Since there is no need to duplicate protocol information and ARP information, the duplication recovery time can be shortened and duplication information management can be minimized.

5 is a flowchart schematically illustrating a method for operating a control station in a wireless communication system according to an embodiment of the present invention. The control station operating method in the wireless communication system shown in FIG. 5 is a method applicable when both the controller control station and the member control station can perform the control plane function and the data plane function.

First, when a request for a new service flow is received by a controller control station included in a control station cluster formed by clustering a plurality of control stations (S500), the controller control station selects a control station to process the corresponding service flow in the control station cluster. Select (S510). At this time, the controller control station may select itself as well as the member control station as a control station to process the corresponding service flow.

At this time, each base station has the IP address of the controller control station is set to the default control station, the configuration file of the controller control station includes the IP address of the member control stations managed by the base station, the configuration file of the member control station The IP address of the controller control station of the control station cluster to which it belongs is included.

In one embodiment, in selecting a control station to process a service flow, the controller control station may calculate its load to select a member control station if its load is greater than or equal to a threshold, where the controller control station may By using the robin method, one of the member control stations can be selected, or the member control station having the least load among the member control stations can be selected. On the other hand, if the calculated load of his own is below the threshold, he can select himself.

In S510, when the controller control station selects itself as the control station to process the service flow, the control plane function performing unit of the controller control station performs the control plane function for processing the corresponding service flow (S520), and the control plane function. After the execution of the data plane function execution unit performs a data plane function for processing the corresponding service flow (S530).

On the other hand, in S510, when the controller control station selects any one of the member control stations to the control station to process the service flow, the controller control station transmits the control station selection notification to the selected member control station (S540). Subsequently, the control plane function execution unit of the member control station receiving the control station selection notification performs a control plane function for processing the corresponding service flow (S550), and when the control plane function execution is completed, the data plane function execution unit of the member control station The data plane function for processing the corresponding service flow is performed (S560).

6 is a flowchart showing in more detail a method for operating a control station in a wireless communication system when the controller control station is selected as the control station to process the service flow.

Referring to FIG. 6, first, a sector setting and broadcast information notification process is performed through acquisition of a downlink channel, synchronization of a media access control (MAC), and acquisition of an uplink channel parameter between a terminal and a base station (S610). Next, an initial radio access procedure is performed by transmitting and receiving an Initial RNG-REQ / RNG-RSP message between the UE and the base station (S612). In more detail, the terminal transmits an Initial RNG-REQ, which is an initial ranging request message including a predetermined code, to the base station so as to request information for initial timing synchronization. In response, the base station transmits an Initial RNG-RSP to Initial RNG-RSP, which is an initial ranging response message. The terminal transmits predetermined information for success of initial ranging to a terminal.

Thereafter, the terminal transmits an SBC_REQ message including band and modulation information to the base station for Subscriber Station's Basic Capability Negotiation (S614). Next, the base station transmits an MS_PreAttachment_Req message to the controller control station, which is its default control station, to inform that the new terminal has entered the network (S616). At this time, the MS_PreAttachment_Req message includes the information of the terminal entering the network, the authentication policy of the terminal, the information of the base station and the like.

Upon receiving the MS_PreAttachment_Req message, the controller control station generates a new context for the terminal entering the network and transmits an MS_PreAttachment_Rsp message to the base station to inform the base station of the fact (S618).

After receiving the MS_PreAttachment_Rsp message, the base station transmits an SBC-RSP message indicating that the basic capacity negotiation process is completed (S620), and then sends an MS_PreAttachment_Ack message to the controller control station to confirm that the SBC-RSP message has been transmitted to the terminal. It transmits (S622).

Thereafter, the controller control station starts an EAP authentication procedure with the terminal by transmitting an AuthRelay_EAP_Transfer message including an EAP Request / Identity message to the base station (S624). The base station receiving the AuthRelay_EAP_Transfer message relays the EAP Request / Identity message to the terminal in the PKMv2-RSP / EAP-Transfer message (S626), and the terminal receives the PKMv2-REQ / EAP-Transfer message including the EAP Response / Identity-NAI. Respond to the EAP Response / Identity message by transmitting to the base station (S628). Next, the base station relays the Response / Identity-NAI received through the PKMv2-REQ / EAP-Transfer message to the controller control station through the AuthRelay_EAP-Transfer message (S630).

Then, the authentication procedure between the terminal and the AAA server of the HA through the controller control station is performed (S632), the controller control station is successful completion of EAP-based authentication, terminal authentication profile, and terminal M Key or its life time. A notification regarding a security context, such as a security context, is received (S634).

Next, the controller control station transmits the EAP result (EAP success or EAP failure message) to the base station as an EAP Payload TLV in the AuthRelay_EAP_Transfer message (S636). Thereafter, the base station relays the EAP Payload to the terminal in the PKMv2EAP-Transfer / PKM-RSP message (S638). Next, when the controller control station transmits a Key_Change_Directive message to the base station to notify the completion of the EAP authentication procedure (S640), the base station confirms reception of the Key_Change_Directive message by transmitting the Key_Change_Ack message to the controller control station (S642).

Thereafter, a PKMv2 3-way handshake (SA-TEK-Challenge / Request / Response exchange) is performed between the base station and the terminal in order to set predetermined security-related matters for the terminal (S644 to S648).

Next, the terminal acquires a valid TEK key through the exchange of PKMv2 Key-Request / Reply message with the base station for each SA (Security Association) (S650, S652).

Thereafter, when the PKMv2 3-way handshake is completed, the terminal performs an 802.16e registration procedure by transmitting a REG-REQ message to the base station (S654).

Next, when the base station transmits the result of the PKMv2 3-way handshake and the MS REG context parameter to the controller control station in the MS_Attachment_Req message (S656), the controller control station receiving the MS_Attachment_Req message transmits the MS_Attachment_Rsp message to the base station, thereby sending the MS_Attachment_Req message. Answer (S658).

Thereafter, the base station transmits the REG-RSP message to the terminal (S660), and then transmits an MS_Attachment_ACK message to the controller control station to inform the controller controller of the reception of the MS_Attachment_Rsp message and the transmission of the RES-RSP message (S662). ).

Finally, a data path based on the R6 standard is established between the controller control station and the base station (S664), and connections are established through the exchange of DSA-REQ / RSP / ACK messages between the terminal and the base station (S666).

7 is a flowchart showing in more detail a method for operating a control station in a wireless communication system when a member control station is selected as a control station to process a service flow.

Referring to FIG. 7, the processes from S710 to S722 are the same as the processes from S610 to S622 of FIG. 6 illustrating a process in which the controller control station processes a service flow, and thus a detailed description thereof will be omitted.

Upon receiving the MS_Preattachment_Ack message at S722, the controller control station transmits an LBB selection notify message to inform the selected member control station as a control station to process the service flow through a predetermined method (S724), and the member that has received the LBB selection notify message. The control station confirms receipt of the LBB selection notify message by transmitting an LBB selection Ack message to the controller control station (S726). At this time, the member control station to process the service flow can be determined by the round robin method or select the member control station having the smallest load among the member control stations as described above.

Since the processes described in S728 to S770 are the same except that the process described in S624 to S666 shown in FIG. 6 is the same except that the subject of the action is changed from the controller control station to the member control station, detailed description thereof will be omitted.

As shown in FIG. 7, in processing a service flow, the controller control station, which is the default control station, does not process all the service flows, but the control station to process the service flow for a specific service flow in the controller control station. By changing to a member control station, the capacity of the system can be expanded.

8 is a flowchart schematically illustrating a method for operating a control station in a wireless communication system according to another embodiment of the present invention. The control station operating method in the wireless communication system shown in FIG. 8 is a method that can be applied when a controller control station performs a control plane function and a member control station performs a data plane function.

First, when a request for a new service flow is received by a controller control station included in a control station cluster formed by clustering a plurality of control stations (S800), the control plane function execution unit of the controller control station performs a control plane function for processing the corresponding service flow. To perform (S810).

Thereafter, the controller control station selects a control station to perform a data plane function for processing the corresponding service flow among the member control stations (S820). In one embodiment, the controller control station may select a member control station using a round robin method, or select a member control station having the smallest load among the member control stations. At this time, the configuration file of the controller control station includes the IP addresses of the member control stations managed by the controller control station, and the configuration file of the member control station includes the IP address of the controller control station of the control station cluster to which it belongs.

Next, the controller control station transmits a control station selection notification to the selected member control station (S830). Thereafter, the data plane function execution unit of the member control station that receives the control station selection notification performs the data plane function for processing the corresponding service flow (S840).

9 is a flowchart showing in more detail a method of operating a control station in a wireless communication system when the controller control station performs a control plane function and the member control station performs a data plane function.

Processes S910 to S962 represent a process of performing a control plane function for service flow processing, and such a control plane function is performed by a controller control station, and FIG. 6 illustrates a method of processing a service flow by the control control station. Since it is the same as the process from S610 to S662, detailed description thereof will be omitted.

Upon receiving the MS_Attachment_Ack message in S962, the controller control station transmits an LBB selection notify message to inform the selected member control station as a control station to perform the data plane function for processing the service flow through the predetermined method (S966). The member control station receiving the selection notify message confirms receipt of the LBB selection notify message by transmitting an LBB selection Ack message to the controller control station (S968). In this case, the member control station to perform the data plane function for the service flow processing may be determined by the round robin method as described above, or the member control station having the smallest load among the member control stations may be selected.

Subsequently, when the member control station performs a data plane function for service flow processing by establishing a data path according to the R6 standard between the base station (S968), the DSA-REQ / RSP / ACK message is exchanged between the terminal and the base station. Connections are established through (S970).

The control station operating method in the above-described wireless communication system may be implemented in the form of a program that can be executed using various computer means. In this case, the program for performing the control station operating method in the wireless communication system may include a hard disk, It is stored in a computer-readable recording medium such as a CD-ROM, a DVD, a ROM, a RAM, or a flash memory.

Those skilled in the art to which the present invention pertains will understand that the present invention can be implemented in other specific forms without changing the technical spirit or essential features.

For example, in the above-described embodiment, the method of operating the control station in the wireless communication system according to the present invention has been described as being applied in a wireless communication system to which the IEEE802.16d / e, Wibro, WiMAX standard, etc. are applied, but is not limited thereto. Any system capable of providing a wireless communication service using a base station and a control station may be applicable.

Therefore, it is to be understood that the embodiments described above are exemplary in all respects and not restrictive. The scope of the present invention is shown by the following claims rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalent concepts should be construed as being included in the scope of the present invention. do.

1 is a schematic block diagram of a wireless communication system in accordance with an embodiment of the present invention.

2 is a schematic block diagram of a controller control station and a member control station in accordance with an embodiment of the present invention.

3 is a schematic block diagram of a controller control station and a member control station in accordance with another embodiment of the present invention.

4 is a schematic block diagram of a redundancy apparatus according to an embodiment of the present invention.

5 is a flowchart schematically illustrating a method for operating a control station in a wireless communication system according to an embodiment of the present invention.

Fig. 6 is a flowchart showing in detail a method for operating a control station in a wireless communication system when the controller control station is selected as the control station to process the service flow.

FIG. 7 is a flowchart specifically showing a method for operating a control station in a wireless communication system when a member control station is selected as a control station to process a service flow; FIG.

8 is a flowchart schematically illustrating a method for operating a control station in a wireless communication system according to another embodiment of the present invention.

9 is a flowchart specifically showing a method for operating a control station in a wireless communication system in a case where a controller control station performs a control plane function and a member control station performs a data plane function.

Claims (38)

In a control station cluster composed of one controller control station and one or more member control stations, the controller control station selects one of itself or the member control station as a control station for service flow processing. Making; When the member control station is selected, sending, by the controller control station, a control station selection notification including context information of a terminal corresponding to the service flow to the selected member control station; And And processing the service flow by the selected member control station using the context information included in the control station selection notification. 2. The method of operating a control station in a wireless communication system according to claim 1, wherein each of said controller control station and said member control station is dualized into an active control station and a standby control station. The wireless communication system of claim 1, wherein the configuration file of the controller control station includes an IP address of each member control station, and the configuration file of the member control station includes an IP address of the controller control station. Control station operation method in communication system. The method of claim 1, wherein the IP address of the default control station of the base station interworking with the control station cluster is the IP address of the controller control station. The method of claim 1, wherein the step of selecting a control station, By the controller control station calculating its load, And selecting one of the member control stations when the calculated load is greater than or equal to a threshold, and selecting the controller control station when less than a threshold. The method of claim 5, The load of the controller control station is calculated using at least one of the ratio of the maximum number of sessions that the controller control station can support to the number of current sessions, memory usage, and bandwidth usage. How to use the control station. The method of claim 5, wherein in the step of selecting the control station, when the calculated load of the controller control station is greater than or equal to a threshold value, And the controller control station selects a member control station to process the service flow by using a round robin method. The method of claim 5, wherein in the step of selecting the control station, when the calculated load of the controller control station is greater than or equal to a threshold value, Receiving a load of each member control station from the member control station, The controller control station selects a member control station having the least load of each member control station transmitted from the member control station as a member control station to process the service flow. . The method of claim 8, wherein the load of the member controller control station is calculated using at least one of the maximum number of sessions that can be supported by the member control station and the number of current sessions, memory usage, and bandwidth usage. A control station operating method in a wireless communication system. 9. The method of claim 8, wherein the load of each member control station is a predetermined period, when the load of each member control station reaches a threshold, or when the controller control station requests the load of each member control station. The control station operating method in a wireless communication system, characterized in that transmitted from each member control station if at least one of the. The method of claim 1, wherein after the control station selection step, And transmitting identification information of the selected member control station to a base station interworking with the control station cluster. The method of claim 1, wherein after the control station selection notification transmission step: And deleting the context information stored in the controller control station. The method of claim 1, wherein the service flow processing step, Generating, by the selected member control station, new context information for a terminal corresponding to the service flow using the context information included in the control station selection notification; And And performing a control plane function and a data plane function on the service flow by using the new context information. Performing, by the controller control station, a control plane function for service flow in a control station cluster including one controller control station and at least one member control station; Selecting, by the controller control station, a control station to perform a data plane function for processing the service flow among the member control stations; Sending, by the controller control station, a control station selection notification including context information of a terminal corresponding to the service flow to the selected member control station; And And performing, by the selected member control station, the data plane function for the service flow processing by using the context information included in the control station selection notification. . 15. The method of operating a control station in a wireless communication system according to claim 14, wherein each of said controller control station and said member control station is dualized into an active control station and a standby control station. 15. The method of claim 14, wherein in the step of selecting a control station, The controller control station selects a member control station to process the service flow using a round robin method, or selects a member control station having the smallest load of each member control station transmitted from the member control station. A method for operating a control station in a wireless communication system, characterized in that the flow is selected as a member control station to process. 17. The method of claim 16, wherein the load of the member controller control station is calculated using at least one of the maximum number of sessions that the member control station can support and the number of current sessions, memory usage, and bandwidth usage. A control station operating method in a wireless communication system. 17. The method of claim 16, wherein the load of each member control station is a predetermined period, when the load of each member control station reaches a threshold, or when the controller control station requests the load of each member control station. The control station operating method in a wireless communication system, characterized in that transmitted from each member control station if at least one of the. 15. The method of claim 14, wherein after the control station selection step, And transmitting identification information of the selected member control station to a base station interworking with the control station cluster. 15. The method of claim 14, wherein after the control station selection notification transmission step: And deleting the context information stored in the controller control station. When selecting a control station for service flow processing in a control station cluster generated by clustering a plurality of control stations, but selecting a control station other than itself, the service is selected by the selected control station. A controller control station for transmitting a control station selection notification including context information of a terminal corresponding to the flow; And And at least one member control station for processing the service flow using the context information included in the control station selection notification when the control station selection notification is received from the controller control station. . 22. The wireless communication system according to claim 21, wherein each of said controller control station and said member control station is redundant with an active control station and a standby control station. 22. The wireless device of claim 21, wherein the configuration file of the controller control station includes the IP address of each member control station, and the configuration file of the member control station includes the IP address of the controller control station. Communication system. 22. The wireless communication system according to claim 21, wherein the IP address of the default control station of the base station interworking with the control station cluster is the IP address of the controller control station. The method of claim 21, wherein each of the control and member control station, Calculate the load of the control station, and if the control station is set as a controller control station, selecting either the controller control station or the member control station as the control station to process the service flow according to the calculated load, the member When the control station is selected, the control station selection notification is transmitted to the selected member control station, and when the control station is set as a member control station, the calculated load is transmitted to the controller control station and the controller control station receives the A load balancing unit configured to receive a control station selection notification; A control plane function performing unit configured to authenticate a service flow request and generate context information of a terminal corresponding to the service flow to perform a control plane function for service flow processing; And And a data plane function performing unit for generating or managing data paths and processing data packets through tunneling with a home agent to perform data plane functions for service flow processing. The method of claim 25, wherein the load balancing unit, In selecting a control station to process a service flow when the control station is set as a controller control station, selecting one of the member control stations when the calculated load is greater than or equal to a threshold, and selecting the controller control station when less than a threshold. Wireless communication system, characterized in that the selection. The method of claim 26, wherein the load balancing unit, In the case where the control station is set as a controller control station, in selecting one of the member control stations as a control station to process the service flow, member control to process the service flow using a round robin method. Selecting a station or selecting a member control station having the least load of each member control station transmitted from the member control station as a member control station to process the service flow. The method of claim 27, wherein the load balancing unit, When the control station is set as a member control station, at a predetermined period, at least when the load of each member control station reaches a threshold, or when the controller control station requests the load of each member control station. And if one is satisfied, transmitting the load of each member control station to the controller control station. The method of claim 25, wherein the load balancing unit, And calculating a load of the control station by using at least one of a ratio of the maximum number of sessions supported by the control station to the number of current sessions, memory usage, and bandwidth usage. The control plane function performing unit of the controller control station, And when the load balancing unit transmits the control station selection notification to the member control station, deletes the context information stored in the controller control station. The control plane function performing unit of the controller control station, And transmitting identification information of the selected member control station to a base station interworking with the control station cluster. The method of claim 24, The control plane function performing unit of the member control station generates new context information for the terminal corresponding to the service flow by using the context information included in the control station selection notification transmitted from the controller control station, and generates the new context information. Performs a control plane function on the service flow using context information, And a data plane function performing unit of the member control station performs a data plane function for processing the service flow by using the new context information. Selects a control station other than itself in the control station cluster generated by performing a control plane function for service flow processing and clustering a plurality of control stations as a control station to perform a data plane function for service flow processing. A controller control station for transmitting a control station selection notification including context information of a terminal corresponding to the service flow to the selected control station; And And a member control station performing a data plane function for the service flow processing by using the context information included in the control station selection notification when the control station selection notification is received from the controller control station. Wireless communication system. 34. The wireless communication system according to claim 33, wherein each of the controller control station and the member control station is redundant by including an active device and a standby device. The method of claim 33, wherein the controller control station, A member control station determined by a round robin method or a control station having the least load among each member control station is selected as a control station to perform a data plane function for processing the service flow, and the service flow is performed to the selected member control station. A load balancing unit for transmitting a control station selection notification including context information of a terminal corresponding to the control unit; And And a control plane function performing unit configured to perform a control plane function for service flow processing by authenticating a service flow request and generating context information of a terminal corresponding to each service flow. The method of claim 33, wherein the member control station, The calculated load is satisfied when at least one of when the load is calculated by a predetermined period, when the calculated load reaches a threshold, or when the controller control station requests the load of each member control station. A load balancing unit for transmitting the control station selection notification including the context information of the terminal corresponding to the service flow from the controller control station; And And a data plane function performing unit configured to process a data plane function for processing the service flow by generating or managing a data path and processing the data packet through tunneling with a home agent. At least one control station cluster for controlling terminals and base stations in a service area and processing a service flow; The control station cluster is configured by clustering a controller control station and at least one member control station, The controller control station performs a control plane function for the service flow, selects a member control station to perform a data plane function for the service flow, and the selected member control station performs a data plane function for the service flow. And transmit context information of the terminal corresponding to the service flow to the selected member control station to perform. 38. The wireless communication system of claim 37, wherein the number of member control stations to perform data plane functions for the service flow is determined based on the load of the controller control station and the load of the member control station.

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