WO2021199855A1

WO2021199855A1 - Wireless relay system

Info

Publication number: WO2021199855A1
Application number: PCT/JP2021/007973
Authority: WO
Inventors: 剛央植田; 伸彦荒新
Original assignee: パナソニックＩｐマネジメント株式会社
Priority date: 2020-03-31
Filing date: 2021-03-02
Publication date: 2021-10-07

Abstract

A wireless device (110) is provided with a wired transmitting/receiving unit (111), a unique header addition unit (112), a wireless transmitting unit (113), a wireless receiving unit (114), a unique header removal unit (115), and a management table (116). The unique header addition unit (112) adds a unique header to an Ether frame received from the wired transmitting/receiving unit (111) to encapsulate the Ether frame and conceal the address information of the Ether header, thereby compensating for address information lacking in an 802.11 frame and realizing IP communication between terminals that is conducted through two wireless devices.

Description

Wireless relay system

This disclosure relates to a wireless relay system.

As described in Non-Patent Document 1, in order to enable mutual communication with the wired LAN standard in the wireless LAN standard, a field that can store the address information of the wired device other than the wireless device is provided in the frame header. In particular, as shown in FIG. 1, four address fields are used for terminal-to-terminal communication that relays communication between wireless devices called WDS (Wireless Distribution System).

In recent years, terminals equipped with wireless devices such as smartphones and tablets have become widespread, so it is often the case that four address fields are not required. That is, the wireless device 2 (200) of FIG. 1 serves as a terminal, and three address feels are sufficient. Against this background, many wireless device vendors have not developed wireless devices that support WDS. On the other hand, the number of address fields supported by wireless devices is often fixed by hardware and often cannot be easily changed by the user.

The wireless relay system in the present disclosure is a wireless relay system that realizes wireless communication between a first terminal and a second terminal, and is a first wireless device that can be connected to the first terminal and a second. It is provided with a second wireless device that can be connected to a terminal. The first wireless device includes a wireless transmission unit that transmits information to the second wireless device, a management table that records information based on the second terminal connected to the second wireless device, and the above. The data received from the first terminal is provided with a unique header using the management table, and an addition unit for generating a payload of a packet transmitted from the wireless transmission unit. The second wireless device includes a wireless receiving unit and a removing unit that removes a unique header added by the imparting unit from the payload of a packet received by the wireless receiving unit and transmits the original header to the second terminal.

The wireless relay system in the present disclosure can relay communication between access points in the same manner as WDS even when the hardware does not support WDS.

Block diagram of communication that relays communication between wireless devices in WDS A block diagram showing a configuration of a wireless device according to the first embodiment. Frame structure diagram with a unique header used in the wireless device according to the first embodiment The figure which illustrated the management table of the wireless device in Embodiment 1. Flow chart of the operation of the transmission process of the wireless device according to the first embodiment Flowchart of operation of reception processing of wireless device according to the first embodiment The processing step diagram when the ARP packet flows from the terminal in Embodiment 1. Address resolution processing step diagram when an IP packet flows from the terminal in the first embodiment FIG. 5 is a processing step diagram of address resolution when a plurality of wirelessly connected devices are connected in the first embodiment.

Hereinafter, embodiments will be described in detail with reference to the drawings as appropriate. However, more detailed explanation than necessary may be omitted. For example, detailed explanations of already well-known matters and duplicate explanations for substantially the same configuration may be omitted. This is to avoid unnecessary redundancy of the following description and to facilitate the understanding of those skilled in the art.

It should be noted that the accompanying drawings and the following description are provided for those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter described in the claims.

(Embodiment 1)
Hereinafter, the first embodiment will be described with reference to FIGS. 2 to 7.

[1-1. composition]
[1-1-1. Wireless device configuration]
FIG. 2 is a block diagram showing the configuration of the wireless device. The terminal 1 (100) and the wireless device 1 (110), and the terminal 2 (130) and the wireless device 2 (120) are each wiredly connected by an Ether cable. Here, the terminal is hardware such as a PC provided with a wired LAN adapter, and the wireless device is hardware such as a wireless LAN access point. The wireless device 1 (110) and the wireless device 2 (120) are wirelessly connected. In the present embodiment, it is assumed that the wireless connection is made in a format compliant with the IEEE 802.11 wireless LAN standard.

The case of transmitting data from the terminal 1 (100) to the terminal 2 (130) will be described. The Ether frame transmitted from the terminal 1 (100) is received by the wired transmission / reception unit 111 of the wireless device 1 (110), and the original header adding unit 112 stores the address information for communicating in the wireless section. Granted. An 802.11 header is formed based on the original header, and is transmitted as an 802.11 frame from the wireless transmission unit 113, and the frame is received by the wireless reception unit 124 of the wireless device 2 (120). The radio receiver 124 reproduces the original header from the 802.11 header. When this is removed by the original header removing unit 125, the same Ethernet frame transmitted from the terminal 1 (100) can be obtained. Communication is realized by transmitting this Ethernet frame from the wired transmission / reception unit 121 to the terminal 2 (130). Further, the wireless device 2 (120) receives three address information of the MAC address of the opposite wireless device 1 (110), the IP address of the terminal 1 (100), and the MAC address of the terminal 1 (100) when receiving the wireless frame. Record in the management table 126 as a set.

In the present embodiment, the configurations of the wireless device 1 (110) and the wireless device 2 (120) are the same, and when information is transmitted from the terminal 2 (130) to the terminal 1 (100), the same as described above. The same operation is performed with the relationship between the wireless device 1 (110) and the wireless device 2 (120) reversed.

[1-1-2. Original frame structure]
FIG. 3 is a structural diagram of a frame used in the wireless device according to the present embodiment.

200 is an Ethernet frame used in wired communication.

The original header adding unit 112 uses the Ether frame 200 as the payload 212, adds the original header 211 in front of it, and generates the original frame 210. The original header has the same format as the Ether header, and has 6 bytes each for storing the address information of the destination and the sender, and has a 2 byte area as a type information field. Binary code indicating that this header is a unique frame is stored in this type information field (for example, "0xAA66"). By checking the type information field included in the header of the received frame, the wireless device on the receiving side can determine whether the header is a unique frame or not. The contents of the information described in the field for storing the address information will be described later.

The wireless transmission unit 113 creates the 802.11 header 221 based on the original header 211 of the original frame 210, and creates the 802.11 frame 220. At this time, the Ethernet frame 200 is stored as it is in the payload 222 of the 802.11 frame 220.

In the present embodiment, "0xAA66" is given as an example of the value of the type information field indicating that the frame is unique, but the binary code is not limited to this value. Other binary code may be used as long as it can be determined that the header is different from the existing header.

[1-1-3. Management table configuration]
FIG. 4 is a specific configuration example of the management table (116, 126) included in the wireless device. In the field for storing the address information of the original header portion described above, the addresses of the wireless device as the source and the destination are stored. These addresses are acquired by the original header adding unit 112 with reference to the management table 300. In the management table 300, the IP address and MAC address of the terminal and the MAC address of the wireless device connected to the terminal are registered as a set. The original header adding unit 112 acquires the MAC address of the wireless device connected to the terminal from the management table 300 using the MAC address of the destination terminal as a key, and stores it in the destination address field of the original header 211.

The method of updating the information recorded in the management table 300 will be described later.

[1-2. motion]
[1-2-1. Transmission process]
The process from the wireless device 1 (110) receiving the Ether frame from the terminal 1 (100) through the Ether cable to transmitting the wireless frame to the wireless section will be described with reference to the flowchart of FIG.

[Step S400]
The wired transmission / reception unit 111 receives an Ethernet frame from the terminal 1 (100).

[Step S401]
The original header adding unit 112 adds an original header to the Ethernet frame received by the wired transmission / reception unit 111. First, the address of the wireless device 1 (110) itself is stored in the source field of the original header.

[Step S402]
The original header addition unit 112 reads the contents of the destination address of the Ether header included in the Ethernet frame. If the content is a unicast address, the process proceeds to step S403. If it is a broadcast address, the process proceeds to step S410.

[Step S403]
The original header adding unit 112 refers to the management table 116. As described above, the reference performed here is to acquire the MAC address of the wireless device connected to the terminal by using the MAC address of the destination terminal read from the Ether header as a key. If the MAC address of the destination wireless device is registered in the management table 116, the process proceeds to step S404. If it is not registered, the process proceeds to step S408.

At this time, even if the destination MAC address is registered in the management table 116, if there is no record of being referred to for a certain period of time, it may be treated as not registered. This is because the connection relationship may have already been changed.

Although not shown, a process of deleting records on the management table that have not been referenced for a certain period of time may be performed periodically in the wireless device.

[Step S404]
If the MAC address of the destination wireless device is registered in the management table 116, the address of the wireless device is stored in the destination field of the original header.

[Step S405]
This is buffering when the frame generated by the original header adding unit 112 is transmitted from the wireless transmission unit 113.

[Step S406]
The wireless transmitter 113 sequentially processes the buffered frames. The wireless transmission unit 113 generates an 802.11 header from the original header added to the original frame and adds it to the beginning of the frame.

[Step S407]
The wireless transmission unit 113 wirelessly transmits the frame generated in step S406 as an 802.11 frame.

[Step S408]
If the MAC address of the destination wireless device is not registered in the management table, the original header adding unit 112 determines the type of the packet received from the terminal 1 (100). If the packet type is an IP packet, the process proceeds to S409. On the other hand, if it is an ARP packet, the process proceeds to S410.

[Step S409]
The original header addition unit 112 transmits an ARP request packet through the wireless transmission unit 113.

The more detailed processing of the ARP request mentioned in steps S408 and S409 will be described later.

[Step S410]
The original header adding unit 112 stores the broadcast address in the destination field of the original header, and performs wireless transmission processing after S405.

[1-2-2. Reception processing]
The process from the wireless device 120 receiving the wireless frame from the wireless section to transmitting the Ethernet frame to the terminal 2 (130) through the Ether cable will be described with reference to the flowchart of FIG.

[Step S500]
The radio receiver 124 receives the 802.11 frame.

[Step S501]
The radio receiving unit 124 reshapes the original header from the 802.11 header included in the received 802.11 frame.

[Step S502]
This is buffering for the original header removing unit 125 to process the frame generated by the radio receiving unit 124.

[Step S503]
The original header removing unit 125 sequentially processes the buffered frames. The original header removing unit 125 reads out the contents of the destination field of the original header included in the frame. At this time, if the content is unicast and not a frame addressed to itself, this frame is discarded and the process returns to the radio frame reception in step S500. If it is addressed to itself or broadcast, the process proceeds to step S504.

[Step S504]
The original header removing unit 125 refers to the management table 126. The reference made here is to confirm whether or not the MAC address of the source wireless device is registered in the management table 126. If the MAC address of the source wireless device is registered in the management table 126, the process proceeds to step S505 without updating the management table 126. If it is not registered, the process proceeds to step S507.

[Step S505]
The original header removing unit 125 removes the original header from the frame.

[Step S506]
The wired transmission / reception unit 121 transmits the frame output by the original header removal unit 125 as an Ethernet frame to the terminal 2 (130) through the Ethernet cable. When the transmission is completed, the process returns to S500 and waits for the wireless receiver to receive the frame.

[Step S507]
If it is determined in step S504 that the MAC address of the source wireless device is not registered in the management table 126, the original header removing unit 125 determines the packet type. If the packet is an ARP request packet, the process proceeds to step S508. If it is not an ARP request packet, the process proceeds to step S509.

[Step S508]
When the packet is an ARP request packet, the original header removing unit 125 wirelessly transmits the ARP response packet via the wireless transmission unit 123.

[Step S509]
The original header removing unit 125 acquires the MAC address of the wireless device from the original header, the MAC address of the terminal from the Ether header, and the IP address of the terminal from the IP header, and registers them in the management table 126 as a set. After that, the processing after S505 is performed.

[1-2-2. Address information resolution]
In the wireless device, the process until the original header removing unit 125 resolves the address information, updates the management table 126, and can transmit and receive the wireless section by unicast will be described with reference to the explanatory diagrams of FIGS. 7 and 8. do.

FIG. 7 is an explanatory diagram showing an address resolution processing procedure when an ARP request packet is transmitted from a terminal.

[Process 1-1]
An ARP request packet is broadcast from terminal 1 (100) to terminal 2 (130). At this time, it is assumed that the address information of the terminal 2 (130) is not registered in the management table 116 of the wireless device 1 (110).

[Process 1-2]
Terminal 2 (130) transmits an ARP response packet to terminal 1 (100). When the terminal 1 (100) receives the ARP response packet, the terminal 1 (100) extracts information from the original header and the Ether header by using the original header removing unit 115, and updates the management table 116 by the method described above.

[Process 1-3]
Since the terminal 1 (100) can form its own header based on the management table 116, the IP packet can be unicastly transmitted in the wireless section from the wireless device 1 (110) to the wireless device 2 (120).

FIG. 8 is an explanatory diagram showing an address resolution processing procedure when an IP request packet is transmitted from the terminal.

[Processing 2-1]
An IP packet is unicastly transmitted from the terminal 1 (100) to the terminal 2 (130). At this time, it is assumed that the address information of the terminal 2 (130) is not registered in the management table 116 of the wireless device 1 (110). This IP packet can be delivered to the terminal 2 (130), but the wireless section is transmitted by broadcasting.

[Processing 2-2]
The wireless device 1 (110) broadcasts an ARP request packet to the terminal 2 (130) in order to update the management table by itself.

[Processing 2-3]
The terminal 2 (130) transmits an ARP response packet to the wireless device 1 (110). The wireless device 1 (110) that has received the ARP response packet updates the management table 116 by using the original header removing unit 115 in the same procedure as in the above process 1-2.

[Processing 2-4]
The IP packet transmitted from the terminal 1 (100) can be unicastly transmitted in the wireless section from the wireless device 1 (110) to the wireless device 2 (120) in the same procedure as the above process 1-3. ..

In the above procedure, the mode in which the process 2-2 or later is performed after the process 2-1 is generated has been described, but the process 2-2 is performed when the wireless device 1 (110) receives the IP packet from the terminal 1 (100). Subsequent processing may be started, or processing 2-2 or later may be performed in advance so that the wireless device 1 (100) waits for transmission from the terminal 1 (100).

Further, in the present embodiment, only the case where the wireless connections are one-opposed has been described, but even when a plurality of wireless connections are connected as shown in FIG. 9, address resolution is performed in the same manner and the management table is updated to communicate between terminals. Can be realized by unicast.

In addition, in order to simplify the explanation, in this embodiment, the wireless device 1 (100) and the wireless device 2 (200) are directly communicated with each other, but the wireless device 1 (100) and the wireless device 2 (200) are directly communicated with each other. ) May intervene in one or more wireless relay devices. This wireless relay device may have the same characteristics as the wireless device 1 (100) and the wireless device 2 (200), or may be a general wireless relay device. If it has the same characteristics as the wireless device 1 (100) and the wireless device 2 (200), the information stored in the original header is extracted from the relayed information, and the management table of the wireless relay device itself is updated. It may have a function.

[1-3. Effect, etc.]
As described above, in the present embodiment, the wireless device 110 includes a wired transmission / reception unit 111, an original header addition unit 112, a wireless transmission unit 113, a wireless reception unit 114, an original header removal unit 115, and a management table 116. The original header addition unit 112 attaches an original header to the Ether frame received from the wired transmission / reception unit 111, encapsulates the Ether frame 200, and hides the address information of the Ether header, so that the 802.11 frame 220 is insufficient. It supplements the address information and realizes IP communication between terminals that mediate between two wireless devices.

This disclosure enables communication that could not be realized with wireless devices that do not support WDS.

In addition, since the management table is introduced and the wireless device itself also performs address resolution, the time required for broadcast communication in the wireless section can be reduced, and smooth communication can be realized without reducing the speed.

This disclosure is applicable to wireless relay in IP communication between terminals. Specifically, the present disclosure is applicable to a personal computer equipped with an access point or a wireless device.

100, 130

Terminal

110, 120

Wireless device

111, 121 Wired transmitter /

receiver

112, 122 Original

header addition unit

113, 123

Wireless transmitter

114, 124

Wireless receiver

115, 125 Original

header removal unit

116, 126, 300 Management table 200 Ether Frame 210 Original frame 220 802.11 frame

Claims

A wireless relay system that realizes wireless communication between a first terminal and a second terminal.
A first wireless device that can be connected to the first terminal,
A second wireless device that can be connected to the second terminal,
With
The first wireless device is
A wireless transmitter that transmits information to the second wireless device,
A management table for recording information for identifying the second terminal connected to the second wireless device, and
A header is added to the data received from the first terminal using the information recorded in the management table, and an addition unit that generates a payload of a packet transmitted from the wireless transmission unit is used.
With
The second wireless device is
A wireless receiver that receives information from the first wireless device, and
A removing unit that removes the header added by the granting unit from the payload of the packet received by the wireless receiving unit and transmits the payload of the packet to the second terminal.
A wireless relay system equipped with.
The header includes type information indicating the type of the header.
The wireless relay system according to claim 1, wherein the imparting unit adds the header to a frame of the MAC layer received from the first terminal.
The additional part
The wireless relay system according to claim 2, wherein the IP address and the MAC address of the frame of the MAC layer transmitted from the first terminal are not changed.
The first wireless device is
With a management table update section
The management table update unit
The first aspect of claim 1 is characterized in that the management table is updated using the contents of the ARP request transmitted by the first wireless device and the ARP response transmitted by the second wireless device in response to the ARP request. The described wireless relay system.
The management table update unit
The MAC address of the second wireless device and the IP address and MAC address of the second terminal connected to the second wireless device are extracted from the ARP response packet and header of the second wireless device. The wireless relay system according to claim 4, wherein the management table is updated.