Radio base station, control method, and program

Abstract

To provide a radio base station, a control method, and a program, for suppressing deterioration of a throughput.SOLUTION: A radio base station comprises: a first communication part 201 that transmits and receives a communication frame in a space of radio terminals wired; a second communication part 202 that transmits and receives the communication frame in a space of the other radio terminals; a storage part 203 that stores radio terminal information as information related to a radio communication acquired at the time of performing a radio connection processing with each radio terminal; a transfer part 204 that determines whether or not a transmission destination address of the communication frame notified from the first communication part 201 or the second communication part 202 is an address of each of the radio terminals under an own device; a change part 205 that changes priority order information stored in a ToS field of the communication frame on the basis of a notification of the transfer part 204; and a control part 206 that controls the communication frame processed by te changing part 205 on the basis of the notification of the transfer part 204 so as to is transmitted toward each radio terminal of a transmission destination address from the first communication part 201 or the second communication part 202.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a radio base station, a control method, and a program thereof.

Background Art

[0002] Conventionally, in order to secure a wide range of wireless communication, a WDS (Wireless Distribution System) communication is known in which a plurality of radio base stations (for example, wireless access points) are each arranged within the range where radio waves can reach from each device, and wireless communication is performed while relaying each other's wireless communication. In the radio base station in the WDS communication, by using only a single radio interface, both communication with a wireless terminal (infrastructure communication) and wireless communication between radio base stations can be realized with a relatively simple configuration. On the other hand, in WDS communication, all of the wireless terminal and the radio base stations need to use the same radio channel. For example, as the number of wireless terminals and radio base stations increases or high-load communication occurs, the communication quality of wireless communication deteriorates, such as the throughput being significantly reduced by squeezing the communication bandwidth between radio base stations.

[0003] In order to solve such problems, in the technique disclosed in Patent Document 1, in wireless communication between a plurality of radio communication base stations, by using different frequency channels for relay wireless transmission and relay wireless reception in one radio communication base station, a decrease in throughput in wireless communication between a plurality of radio communication base stations is suppressed, and high communication performance is maintained.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the wireless communication base station of the wireless communication system disclosed in Patent Document 1, different channels are used for relay wireless transmission and relay wireless reception to perform wireless communication between multiple wireless communication base stations. As the number and locations of wireless communication base stations increase, the number of channels required for wireless communication also increases. For this reason, in environments where there are already few channels available for wireless communication (for example, many existing wireless communication devices, or predetermined channels), the wireless communication base station cannot be said to be suitable for wireless communication between multiple wireless communication base stations (WDS communication). Furthermore, the wireless communication base station needs to have vendor-specific functions, which reduces its versatility and impairs user convenience.

[0006] This invention has been made in view of the above circumstances, and aims to provide a wireless base station that suppresses throughput degradation and maintains high communication performance in a communication system composed of multiple wireless base stations, while also taking user convenience into consideration. [Means for solving the problem]

[0007] To solve the above problems, a wireless base station according to one aspect of the present invention is a wireless base station in a communication system in which a plurality of wireless base stations communicate wirelessly with each other, and each wireless terminal connected to each wireless base station communicates wirelessly, and comprises: a first communication unit that sends and receives communication frames with the wireless terminals under its control; a second communication unit that sends and receives communication frames with other wireless base stations; a storage unit that stores wireless terminal information, which is information relating to wireless communication acquired during wireless connection processing with a wireless terminal; a forwarding unit that determines whether the destination address of a communication frame notified by the first communication unit or the second communication unit is the address of each wireless terminal under its control; a modification unit that changes priority information stored in the ToS field of a communication frame based on the notification from the forwarding unit; and a control unit that controls the first communication unit or the second communication unit to send the communication frame processed by the modification unit to the wireless terminal at the destination address based on the notification from the forwarding unit.

[0008] According to this, in wireless communication between multiple wireless base stations, priority is given to wireless communication between adjacent wireless base stations, thereby ensuring sufficient communication bandwidth and suppressing a decrease in throughput in wireless communication between multiple wireless base stations.

[0009] Furthermore, if the destination address of a communication frame notified to the forwarding unit by the first communication unit is not the address of a wireless terminal under its control, the modification unit will cause the communication frame to be transmitted with at least a medium priority.

[0010] According to this, a wireless base station can prioritize wireless communication with adjacent wireless base stations over wireless communication with its subordinate wireless terminals.

[0011] Furthermore, if the modification unit determines that the destination address of the communication frame notified by the second communication unit is destined for a wireless terminal under its control, it may rewrite the priority information stored in the ToS field of the communication frame to medium (best effort).

[0012] According to this, a wireless base station can perform wireless communication with its subordinate wireless terminals with appropriate priority.

[0013] Furthermore, if the modification unit determines that the destination address of the communication frame notified by the second communication unit is not destined for a wireless terminal under its control, it may transmit the frame to another adjacent wireless base station without rewriting the priority information stored in the ToS field of the communication frame.

[0014] According to this, a wireless base station can autonomously control its communication so that wireless communication with adjacent wireless base stations takes higher priority than wireless communication with its subordinate wireless terminals.

[0015] Furthermore, a control method according to one aspect of the present invention is a control method for a radio base station in a communication system in which a plurality of radio base stations communicate with each other wirelessly, and each wireless terminal connected to each radio base station communicates wirelessly, and may include: a first communication step of sending and receiving communication frames with the wireless terminals under its control; a second communication step of sending and receiving communication frames with other radio base stations; a storage step of storing wireless terminal information which is information relating to wireless communication acquired during wireless connection processing with a wireless terminal; a forwarding step of determining whether the destination address of the communication frame notified from the first communication step or the second communication step is the address of each of the wireless terminals under its control; a modification step of changing priority information stored in the ToS field of the communication frame based on the notification from the forwarding step; and a control step of controlling the transmission of the communication frame processed in the modification step from the first communication step or the second communication step to the wireless terminal at the destination address based on the notification from the forwarding step.

[0016] According to this, the control method will have the same effect as the wireless base station described above.

[0017] Furthermore, a program according to one aspect of the present invention is a program for causing a computer to execute the above-described control method.

[0018] According to this, the program will have the same effect as the wireless base station described above. [Effects of the Invention]

[0019] According to the present invention, in a communication system in which multiple wireless base stations communicate with each other wirelessly, the wireless base station can suppress a decrease in throughput and maintain high communication performance. [Brief explanation of the drawing]

[0020] [Figure 1] Figure 1 is a schematic diagram showing an overview of the communication system according to the embodiment. [Figure 2]FIG. 2 is a block diagram showing a functional configuration of a radio base station according to an embodiment. [Figure 3] FIG. 3 is a flowchart showing the operation of a radio base station according to an embodiment. [Figure 4] FIG. 4 is an explanatory diagram showing an example of a radio frame transmitted and received between a radio base station according to an embodiment and another radio base station. [Figure 5] FIG. 5 is an explanatory diagram showing an example of priority information stored in a radio frame transmitted from the device itself by a radio base station according to an embodiment. [Figure 6] FIG. 6 is an explanatory diagram showing an example of case-by-case processing based on the source address and destination address of a communication frame among the operations of a radio base station according to an embodiment.

Embodiment for Carrying Out the Invention

[0021] Hereinafter, the embodiments will be specifically described with reference to the drawings. All of the embodiments described below show preferred specific examples of the present invention. The numerical values, shapes, components, arrangement positions and connection forms of the components, steps, order of steps, etc. shown in the following embodiments are merely examples and are not intended to limit the present invention. In addition, among the components in the following embodiments, the components not described in the independent claims indicating the highest concept of the present invention are described as optional components constituting a more preferred form. Note that the same reference numerals are assigned to the same components, and the description may be omitted.

[0022] (Embodiment) In the present embodiment, in a communication system in which a plurality of radio base stations perform wireless communication with each other, a radio base station that suppresses a decrease in throughput and maintains high communication performance will be described.

[0023] FIG. 1 is a schematic diagram showing an overview of a communication system 100 according to the present embodiment.

[0024] As shown in Figure 1, the communication system 100 comprises wireless base stations 1a, 1b, and 1c, wireless terminals 11a and 11b, wireless terminal 12, wireless communication link 15, and wireless communication link 16. The communication system 100 is a wireless communication system installed in, for example, a factory or office. Hereinafter, wireless base stations 1a, 1b, and 1c will be collectively referred to as wireless base station 1. Similarly, wireless base stations 11a and 11b will be collectively referred to as wireless terminal 11.

[0025] In this embodiment, the communication system 100 includes three wireless base stations 1a, 1b, and 1c, but it is not limited to this, and the number of wireless base stations included in the communication system 100 may be four or more. Also, in this embodiment, the communication system 100 includes wireless terminals 11a and 11b and wireless terminal 12, but it is not limited to this, and each of the wireless base stations 1 may be connected to multiple wireless terminals.

[0026] The wireless base station 1 performs wireless communication with wireless terminals 11 and 12 via the wireless communication link 16. As shown in Figure 1, the wireless base station 1a performs wireless communication by sending and receiving wireless frames to and from each of the wireless terminals 11 via the wireless communication link 16. The wireless base station 1a also relays wireless frames transmitted from wireless terminal 11a via the wireless communication link 16 and transmits those frames to wireless terminal 11b, or vice versa, relays wireless frames transmitted from wireless terminal 11b and transmits those frames to wireless terminal 11a. The wireless base station 1 is, for example, a wireless access point.

[0027] Wireless terminals 11 and 12 connect to the wireless base station 1 and perform wireless communication compliant with wireless communication standards such as IEEE 802.11ac. Wireless terminals 11 and 12 are, for example, personal computers or smartphones.

[0028] Wireless communication link 15 is the communication path used for wireless communication between each wireless base station 1. Wireless communication link 15 may also be configured as WDS communication. Wireless communication link 15 conforms to wireless communication standards such as IEEE 802.11ac and uses, for example, the 2.4 GHz frequency band to perform wireless communication between each wireless base station 1. However, the communication standards and frequency bands used in wireless communication link 15 are not limited to IEEE 802.11ac and the 2.4 GHz band, but may be any wireless communication standards and frequency bands that can be processed by the wireless circuitry of each wireless base station 1.

[0029] Wireless communication link 16 is the communication path used when wireless base station 1 performs wireless communication with its subordinate wireless terminals 11 and 12, and operates, for example, in infrastructure mode. Furthermore, it is preferable that wireless communication link 16 conforms to wireless communication standards such as IEEE 802.11ac and uses a different frequency band than the one used by wireless communication link 15. The communication standard used in wireless communication link 16 is any wireless communication standard and frequency band that can be processed by the wireless circuits of both wireless base station 1 and wireless terminal 11.

[0030] Figure 2 is a block diagram showing the functional configuration of the wireless base station 1 according to this embodiment. The wireless base station 1 comprises a first communication unit 201, a second communication unit 202, a storage unit 203, a transfer unit 204, a modification unit 205, and a control unit 206. The wireless base station 1 is a type of computer, and in cooperation with each piece of hardware, the CPU (Central Processing Unit) reads the program stored in the storage unit 203 into the main memory and executes it.

[0031] The first communication unit 201 transmits and receives communication frames with each of the wireless terminals 11 and 12 under the control of the wireless base station 1 (its own device). The first communication unit also determines whether or not it has received a communication frame from each of the wireless terminals 11 and 12. The first communication unit 201 is implemented using a wireless module, an antenna (not shown), and a driver program for the wireless module, and communicates wirelessly with each of the wireless terminals 11 and 12 in accordance with wireless communication standards such as IEEE802.11ac.

[0032] The second communication unit 202 transmits and receives communication frames with other wireless base stations 1. The second communication unit also determines whether or not it has received a communication frame from another wireless base station. The second communication unit 202 is implemented using a wireless module, antenna (not shown), and driver program for the wireless module, etc., which are separate from those that make up the first communication unit, and performs wireless communication with other wireless base stations 1 in accordance with wireless communication standards such as IEEE802.11ac.

[0033] The memory unit 203 stores various setting information related to wireless communication, information that should be temporarily stored during communication processing, and so on. Specifically, the memory unit 203 stores device information of the device (wireless base station 1) (for example, the channel used for wireless communication, BSSID, SSID, authentication method, encryption method, etc.). It also stores information on wireless terminals that the device can connect to. Wireless terminal information is, for example, information related to wireless communication obtained during wireless connection processing with a wireless terminal (for example, the MAC address, IP address, security information of the wireless terminal, etc.). The memory unit 203 may be implemented as a volatile storage device such as RAM, or as a non-volatile storage device such as eMMC (Embedded Multimedia Card), SSD (Solid State Drive), or HDD (Hard Disk Drive). Furthermore, as will be described later, the memory unit 203 stores IP prudence values ​​associated with access categories.

[0034] The transfer unit 204 determines whether the destination address of the communication frame notified by the first communication unit is the address of each of the wireless terminals 11 and 12 under its control (for example, wireless terminal 11b). Specifically, it makes this determination by referring to the wireless terminal information under its control stored in the storage unit 203, while examining the header information of the communication frame. The transfer unit 204 then notifies the control unit 206 to transmit the communication frame notified by the modification unit 205 to the wireless terminal (for example, wireless terminal 12) specified in the destination address via the first or second communication unit. The transfer unit 204 may be implemented as a computer using a CPU or RAM (Random Access Memory), or as a program that achieves a similar determination effect.

[0035] The modification unit 205 modifies the access category (details described later) stored in the ToS field of the communication frame based on the notification from the forwarding unit 204, and returns it to the forwarding unit 204. Specifically, based on the notification from the forwarding unit 204, it rewrites the IP precedence value stored in the ToS field of the IP head of the communication frame to the IP precedence value corresponding to the access category. The modification unit 205 also recalculates the checksum value of the IP header if the IP precedence value stored in the ToS field has been changed. The modification unit 205 may be implemented in the form of a computer using a CPU, RAM, etc., or it may be implemented in the form of a program that has the same determination effect.

[0036] The control unit 206 controls the first communication unit to transmit the communication frame processed by the modification unit 205, based on the notification from the transfer unit 204, to the wireless terminal at the destination address. The control unit 206 also controls the second communication unit to transmit the communication frame processed by the modification unit 205, based on the notification from the transfer unit 204, to the adjacent wireless base station at the destination address. The control unit 206 may be implemented as a computer using a CPU or RAM (Random Access Memory), or as a program that achieves a similar determination effect.

[0037] Next, using Figures 4 and 5, the communication using WMM (Wi-Fi Multimedia) in the wireless base station 1 according to this embodiment will be described in detail. Note that WMM is a known technology in Wi-Fi (registered trademark) that sets priorities to process specific communications first when simultaneously sending and receiving multiple types of data handled by a wireless LAN.

[0038] Figure 4 shows an example of a communication frame (Ethernet frame) in the communication system 1 according to this embodiment.

[0039] The Ethernet frame 40 shown in Figure 4 represents a packet transmitted and received in TCP / IP communication, and is mainly composed of an Ethernet header, IP header, TCP header, variable-length data, and FCS (Frame Check Sequence). The IP header of the Ethernet frame 40 is further composed of fields such as version 41, header length 42, ToS (Type of Service) 43, options 44, and padding 45. Version 41 stores the IP version. Header length 42 stores the size of the IP header. ToS 43 is used to assign priority to the IP packet, and the first (most significant) 3 bits of the 8 bits contain the IP precedence. IP precedence is divided into 8 levels from 0 to 7, with a higher value indicating a higher priority for that frame. Options 44 stores any options such as timestamps and soul routing. Padding 45 is used to pad the IP header with zeros so that it fits within a multiple of 4 (e.g., 32 bits).

[0040] In the wireless base station 1 of this embodiment, the IP precedence values ​​to be set in the ToS43 included in the IP header shown in Figure 4 are associated with each access category used in the WMM shown in Figure 5, which will be described next, and are stored in the storage unit 203 in advance.

[0041] The priority information 50 shown in Figure 5 is a list of priorities used by the wireless base station 1 according to this embodiment to identify the priority of communication frames. The priority information 50 is stored in the storage unit 203 of the wireless base station 1 and is referenced based on notifications from the transfer unit 204 and the modification unit 305. In WMM, the priority information 50 shows the relationship between the access categories to which bandwidth is allocated in order of priority and the priority levels (four levels from highest to lowest) defined for each access category.

[0042] An access category is information that indicates the type of communication (traffic type 52) of an IP packet in communication using WMM. Specifically, there are four access categories as shown in Figure 5, and four levels of priority 51 are defined for IP packets. Voice (AC_VO) is assigned to IP packets related to voice communication. The priority 51 of AC_VO is 1 (highest), making it the highest priority among the four. Video (AC_VI) is assigned to IP packets related to video. The priority 51 of AC_VI is 2 (high). Best effort (AC_BE) is assigned to IP packets where best effort communication is desired. AC_BE is assigned to IP packets of normal data, where the level of immediacy required is lower than that of voice and video. The priority 51 of AC_BE is 3 (medium). Background (AC_BK) is assigned to IP packets where background communication is desired. AC_BK is assigned, for example, to IP packets of data that is not constrained by the timing of transmission (especially large amounts of data that take a long time to transmit). The priority of AC_BK is 4, which is the lowest priority. The four access categories are assigned priorities based on the IP precedence value set in the ToS field of the IP header shown in Figure 4. For example, the IP precedence value is set to "111" for access category AC_VO (highest priority), to "011" for AC_BE (medium priority), and to "001" for AC_BK (low priority).

[0043] In the communication system 100 of this embodiment, a network is established that consists of multiple wireless base stations 1, enabling wireless communication between adjacent wireless base stations 1. The following describes in detail the operations according to each wireless communication environment, using Figures 3 and 6, for cases where wireless communication is performed from a wireless terminal under a predetermined wireless base station 1 to a wireless terminal under another wireless base station 1 via the device, and for cases where wireless communication is performed from a wireless terminal under a predetermined wireless base station 1 to another wireless terminal under the device via the device.

[0044] Figure 3 is a flowchart showing an example of the operation of the wireless base station 1 according to this embodiment.

[0045] In step S301, the first communication unit 201 or the second communication unit 202 of the wireless base station 1 determines whether or not it has received a communication frame. If the first communication unit 201 or the second communication unit 202 has received a communication frame, it proceeds to step S302 (Yes in step S301). On the other hand, if it does not receive a communication frame, it repeats step S301 and enters a waiting state for reception (No in step S301).

[0046] In step S302, the first communication unit 201 or the second communication unit 202 determines whether it has received a communication frame from a subordinate wireless terminal 11 or from another wireless base station. If the first communication unit 201 receives a communication frame from a subordinate wireless terminal 11, it notifies the forwarding unit 204 of the destination address of the communication frame and proceeds to step S303 (step S302(a)). On the other hand, if the second communication unit 202 receives a communication frame from another wireless base station 1, it notifies the forwarding unit 204 of the destination address of the communication frame and proceeds to step S304 (step S302(b)).

[0047] In step S303, the forwarding unit 204 determines whether the destination address of the communication frame notified by the first communication unit 201 is the address of a wireless terminal 11 under its control (for example, wireless terminal 11b). If the forwarding unit 204 determines that the destination address matches the address of a wireless terminal 11 under its control, it proceeds to step 306 (Yes in step S303). On the other hand, if the destination address does not match the address of a wireless terminal 11 under its control, it notifies the modification unit 205 of this fact and proceeds to step S305 (No in step S303).

[0048] In step S305 (i.e., in the case of a frame to be transmitted from a subordinate communication terminal to another wireless base station), the modification unit 205 causes the communication frame to be transmitted with at least a medium priority. Specifically, based on the notification from the forwarding unit 204 (No. in step S303), the modification unit 205 rewrites the IP precedence value stored in the Tos43 of the communication frame to an access category of medium or higher. For example, it performs a process to rewrite it to the IP precedence value corresponding to the highest priority AC_VO (Voice) (e.g., "111") and recalculates the checksum value of the IP header. The modification unit 205 notifies the forwarding unit 204 of the communication frame after this processing and proceeds to step S307.

[0049] In step S304, the forwarding unit 204 determines whether the destination address of the communication frame notified by the second communication unit 202 is destined for a wireless terminal under its control. More specifically, it makes this determination by referring to the wireless terminal information under its control stored in the storage unit 203. If the destination address of the communication frame is destined for a wireless terminal under its control, the forwarding unit 204 notifies the modification unit 205 of this fact and proceeds to step S306 (Yes in step S304). On the other hand, if it is not destined for a wireless terminal under its control, the modification unit 205 notifies the forwarding unit 204 of the communication frame and proceeds to step S307 (No in step S304). In this case, the IP precedence value should have already been changed to the highest value by another wireless base station of this system and is not rewritten.

[0050] In step S306 (i.e., in the case of a frame whose destination is a subordinate communication terminal), the modification unit 205, based on the notification from the forwarding unit 204 (Yes in step S304), rewrites the IP precedence value stored in ToS43 of the communication frame to the IP precedence value corresponding to AC_BE (Best Effort), which is the middle of the access category (for example, "011"), and recalculates the checksum value of the IP header. The modification unit 205 notifies the forwarding unit 204 of the communication frame after this processing and proceeds to step S308.

[0051] In step S307, the transfer unit 204 notifies the control unit 206 to transmit the communication frame (a communication frame whose priority has been rewritten to a medium or higher priority) that it received notification of from the modification unit 205 in step 305 to the wireless terminal at the destination address (for example, wireless terminal 12) via the second communication unit 202 (i.e., notify it to transmit it to the wireless terminal at the destination address via the other wireless base station 11). The transfer unit 204 also notifies the control unit 206 to transmit the communication frame (i.e., a communication frame received from the other wireless base station 1) that it received notification of from the modification unit 205 in step 304 to the wireless terminal at the destination address (for example, wireless terminal 12) via the second communication unit 202 (i.e., notify it to transmit it to the wireless terminal at the destination address via the other wireless base station 1). Based on the notification from the transfer unit 204, the control unit 206 controls the second communication unit 202 to transmit the frame to the wireless terminal at the destination address. Subsequently, the second communication unit 202 transmits the communication frame to an adjacent radio base station (for example, radio base station 11b).

[0052] In step S308, the transfer unit 204 notifies the control unit 206 to transmit the communication frame (the communication frame whose priority has been rewritten to medium) that it received notification of from the modification unit 205 in step S306, from the first communication unit 201 to the wireless terminal at the destination address (for example, wireless terminal 11b). Based on the notification from the transfer unit 204, the control unit 206 controls the first communication unit to transmit the frame to the wireless terminal at the destination address. Subsequently, the first communication unit 201 transmits the communication frame to a wireless terminal under its control (for example, a wireless base station 11b).

[0053] Here, in the series of operations of the wireless base station 1 performed in steps S302 to S306 shown in Figure 3, the processing performed by the modification unit 205 based on the source address and destination address of the communication frame is summarized using Figure 6.

[0054] Figure 6 is an explanatory diagram showing an example of how the processing performed based on the source address and destination address of a communication frame is divided into different cases in a series of operations of the wireless base station 1 according to the embodiment.

[0055] If the source address of the communication frame is (a) a subordinate wireless terminal, and the destination address is transmitted to the wireless terminal via another wireless base station (specifically, an adjacent wireless base station) (No. in step S303 of Figure 3), the modification unit 205 performs the process of rewriting the IP precedence value stored in ToS43 of the communication frame to the IP precedence value corresponding to (1) access category AC_VO(Voice).

[0056] If the source address of the communication frame is (a) a subordinate wireless terminal and the destination address is to be sent to another subordinate wireless terminal (specifically, another subordinate wireless terminal 11) (Yes in step S303 of Figure 3), the modification unit 205 performs the process of rewriting the IP precedence value stored in ToS43 of the communication frame to the IP precedence value corresponding to (2) access category AC_BE (Best Effort).

[0057] If the source address of the communication frame is (b) another radio base station (specifically, a radio terminal 11 under the control of another radio base station), and the destination is to be transmitted to a radio terminal via another radio base station (specifically, an adjacent radio base station) (No. in step S304 of Figure 3), the modification unit 205 processes a notification to the forwarding unit 204 of the communication frame. In other words, the modification unit 205 notifies the forwarding unit 204 of the ToS43 of the communication frame received by the second communication unit 202 without (3) changing it. The IP precedence value in this frame has already been rewritten by another radio base station of this system to the IP precedence value corresponding to the access category AC_VO (Voice).

[0058] If the source address of the communication frame is (b) another radio base station (specifically, a radio terminal 12 under another radio base station) and the destination address is to a subordinate radio terminal (specifically, another subordinate radio terminal 11) (Yes in step S304 of Figure 3), the modification unit 205 performs the process of rewriting the IP precedence value stored in ToS43 of the communication frame to (2) the IP precedence value corresponding to access category AC_BE (Best Effort).

[0059] (summary) In conventional wireless communication following WMM, the access category was automatically determined according to the type of IP packet transmitted from the wireless terminal (traffic type such as voice or video), and the wireless base station controlled the wireless communication. In this respect, in the wireless base station 1 according to this embodiment, when the wireless base station 1 relays communication frames transmitted from wireless terminals 11 and 12, (1) when a wireless terminal 11 (e.g., wireless terminal 11a) under its own device (e.g., wireless base station 1a) communicates with a wireless terminal 12 under another wireless base station 1 (e.g., wireless base station 1c), the ToS43 in the IP header of the communication frame is rewritten to a value corresponding to AC_VO, which is the highest access category (priority 1), regardless of the actual traffic type, and transmitted to the adjacent wireless base station 1 (e.g., wireless base station b). As a result, in the communication system of this embodiment, each wireless base station can autonomously control wireless communication with adjacent wireless base stations to have a higher priority than wireless communication with wireless terminals under its control. Therefore, in the communication system of the embodiment, wireless communication between multiple wireless base stations (e.g., WDS communication) can secure sufficient communication bandwidth and suppress a decrease in throughput in wireless communication between multiple wireless base stations. On the other hand, (2) when a wireless terminal 11 (e.g., wireless terminal 11a) under its own device (e.g., wireless base station 1a) communicates with another wireless terminal 11 (e.g., wireless terminal 11b) under its control, the ToS43 in the IP header of the communication frame is rewritten to a value corresponding to AC_BE, which is the middle (priority 3) of the access category, and transmitted to the other wireless terminal 11 under its control. As a result, in the communication system of the embodiment, wireless communication between multiple wireless base stations can be prioritized, and a decrease in throughput in wireless communication between multiple wireless base stations can be suppressed. [Industrial applicability]

[0060] This invention can be used for wireless communication between wireless base stations in a communication system composed of multiple wireless base stations. Specifically, it can be applied to wireless base stations that can suppress a decrease in throughput. [Explanation of symbols]

[0061] 100 Communication Systems 1a, 1b, 1c wireless base station 11a, 11b, 12 wireless terminals 15,16 Communication Links 201 First Communications Department 202 Second Communications Department 203 Storage section 204 Transfer section 205 Changes 206 Control Unit Version 41 42 Header length 43 ToS (Service Type) 44 options 45 padding 50 Priority Information 51 Priority 52 Traffic Types

Claims

1. A radio base station in a communication system in which a plurality of radio base stations perform radio communication with each other and subordinate radio terminals connected to each radio base station perform radio communication, a first communication unit that transmits and receives communication frames to and from the subordinate wireless terminal; a second communication unit that transmits and receives communication frames to and from other wireless base stations; a storage unit for storing wireless terminal information, which is information related to wireless communication acquired during wireless connection processing with the wireless terminal; a transfer unit that determines whether or not a destination address of a communication frame notified from the first communication unit or the second communication unit is an address of each of the wireless terminals under the control of the own device; a change unit that changes priority information to be stored in the ToS field of the communication frame based on the notification from the transfer unit; a control unit that controls the communication frame processed by the change unit based on the notification from the transfer unit so that the communication frame is transmitted from the first communication unit or the second communication unit to a wireless terminal having a destination address; A radio base station comprising:

2. When the destination address of the communication frame notified to the forwarding unit by the first communication unit is not an address of the wireless terminal under the own device, the change unit causes the communication frame to be transmitted with at least a medium priority or higher. The radio base station according to claim 1.

3. The modification unit further When the forwarding unit determines that the destination address of the communication frame notified from the second communication unit is addressed to the wireless terminal under the own device, the priority information stored in the ToS field of the communication frame is rewritten to medium (best effort). The radio base station according to claim 2.

4. The modification unit further When the transfer unit determines that the destination address of the communication frame notified from the second communication unit is not addressed to the wireless terminal under the own device, the transfer unit transmits the communication frame to another adjacent wireless base station without rewriting the priority information stored in the ToS field of the communication frame. The radio base station according to claim 2.

5. A method for controlling a radio base station in a communication system in which a plurality of radio base stations perform radio communication with each other and subordinate radio terminals connected to each radio base station perform radio communication, comprising: a first communication step of transmitting and receiving a communication frame to and from the subordinate wireless terminal; a second communication step of transmitting and receiving communication frames to and from another wireless base station; a storage step of storing wireless terminal information, which is information regarding wireless communication acquired during wireless connection processing with the wireless terminal; a transfer step of determining whether or not the destination address of the communication frame notified from the first communication step or the second communication step is the address of each of the wireless terminals under the control of the own device; a changing step of changing priority information to be stored in the ToS field of the communication frame based on the notification of the forwarding step; a control step of controlling the communication frame processed in the change step based on the notification of the transfer step so that the communication frame is transmitted from the first communication step or the second communication step to the wireless terminal of the destination address; A control method comprising:

6. A program for causing a computer to execute the control method according to claim 5.

Images