TWI489807B - Wifi repeater - Google Patents

Description

Communication method and wireless repeater on wireless network

The present invention relates generally to the field of wireless networks, and more particularly to MAC (Media Access Control) layer WiFi (Wireless Fidelity) repeaters.

The wireless network may include access points that allow one or more wireless stations to access the Ethernet LAN (local area network) or across the wirelessly connected Internet to connect the stations to the access point. Wireless networks can also be added to the wireless network to increase the range of wireless access points. A wireless station can be directly associated with a wireless access point. However, when a station leaves the access point range and enters the transponder range, it can be associated with the access point through the repeater, thereby extending the range of the wireless network.

As a wireless technology, WiFi is becoming more mature and popular. It covers a variety of IEEE 802.11 technologies (including 802.11a, 802.11b, 802.11g, and 802.11n) for wireless LAN deployment. Each IEEE 802.11 technology has various scope limitations and is highly dependent on the real deployment environment. WiFi range repeaters (or extenders) are designed to extend the reach of WiFi devices. Most existing WiFi transponders are based on WDS (Wireless Distribution System) technology, or NAT (Network Access Translation) technology, which is limited.

1.WDS based transponder

The WDS-based transponder requires an access point to support WDS. Currently, WDS features are not fully featured in the IEEE or WiFi standards. Therefore, all types of access points support WDS, and the interoperability between different vendors' 802.11 products is not guaranteed. However, the issue of interoperability can be a major impact on the deployment of transponders. For example, the user must use the same WiFi solution for the access point, but this solution cannot be applied to access points that do not support WDS.

In addition, many WDS devices do not support the WPA (WiFi Protected Access) encryption scheme, which is mandatory for passwords in certain operating environments.

2. NAT based transponder

The NAT forwarder is the foundation of the Layer 3 (network layer) solution. Change the IP address of the station and establish an IP mapping table to replace the data. However, some services on the operator's network, such as IPTV, are combined with IP addresses, and changing the IP address of the station will break the continuity of these services. Therefore, NAT forwarders cannot be accepted by such a network. In addition, NAT forwarders also break Layer 2 (data link layer) continuity and do not support several other Layer 2 protocols, such as PPPoE. NAT forwarders also do not support other Layer 3 protocols except IP.

3.MAC disguise transponder

The MAC configurator transponder can replace the original MAC address of any frame, the slave receives its own MAC address, and transmits the modified frame to the access point. In the other direction, when the repeater receives the frame from the access point, the IP information is searched in the packet, and the target MAC address is inversely mapped, and the target MAC address of the frame is replaced by the MAC address of the station ( The MAC address of the repeater itself). The disadvantage of this measure is that the repeater must change the original MAC address of the frame sent by the station, which will break some basic protocol requirements (such as PPPoE). When the station moves across the access point and the repeater, there is no smoothing. Activity.

Therefore, the MAC layer WiFi transponder is required to provide an extension of the range of access points and solve the above problem.

In accordance with one aspect of the present invention, a method of communication over a wireless network is provided. The wireless network has access points, stations, and repeaters with the same network configuration parameters as the access point. The method includes the following steps at the repeater level: establishing a first communication channel with the station; establishing a second communication channel with the access point to identify the MAC address of the station, and replacing the MAC address communicated with the access point; And communicating the data frame between the access point and the station via the first and second communication channels.

In accordance with one aspect of the present invention, a wireless repeater is provided. The wireless repeater includes an access point unit, and a station unit, which is coupled to the access point unit via an internal connection. The access point unit is set with the same configuration parameters of the external access point, and is suitable for establishing a first wireless channel with the external station, so that the frame communicates between the station unit and the external station via the first wireless channel and the internal connection. The station unit is adapted to establish a second wireless channel, such that the frame communicates between the station unit and the external access point via the second wireless channel and the internal connection. The same MAC address setting is set for the station other than the station unit to communicate with the external access point.

The above and other objects, features and advantages of the present invention will become apparent from

In the following description, the gist of the specific examples of the present invention will be described. For the sake of explanation, special configurations and details are specified for a thorough understanding. However, it will be apparent to those skilled in the art that the present invention may be practiced without the details herein.

Figure 1 shows a WiFi network, including a repeater of a specific embodiment of the present invention.

As shown in FIG. 1, the WiFi network includes an access point (AP) and a station (STA) connected to the AP to access the WLAN or the Internet (not shown). When the station is in the AP range, a connection C1 is established between the AP and the station.

The WiFi network also includes a repeater, which has its own range and can overlap with the AP. The repeater sets the identifier (SSID) with the same service of the AP, so that it can replace the data frame and repeat the AP as necessary. As shown in Figure 1, when the station leaves the AP range and enters the transponder range, the connection C1 is interrupted, and the AP and the station communicate with each other, which is the connection between the station and the repeater C2, and between the repeater and the AP. Connect to C3. As such, the range of the WiFi network extends due to the repeater.

Fig. 2 is a block diagram showing the structure of the repeater shown in Fig. 1. As shown in Figure 2, the repeater includes an access point component and a station component coupled to the access point component via internal connection C4. It is easy to know that these transponder components and the connections between them can be implemented in various forms of hardware, software or a combination thereof.

In order to repeat the AP on the network, the access point component of the repeater constitutes the same configuration parameters as the associated AP, such as SSID (AP-SSID), security method (not shown), and key (not shown).

As shown in Figure 2, the station components of the repeater form the same MAC address (MAC1) with the associated station. As can be seen from the following description, this solution maintains the continuity of the link layer when the STA moves from the AP range mode to the repeater range mode.

Next, the operation process of the WiFi repeater according to an embodiment of the present invention will be described in detail.

Figure 3 shows the AP range in the WiFi network shown in Figure 1.

When standing in the AP range, the AP and the STA communicate in a normal mode, that is, through a wireless connection C1 constructed therebetween. In this case, neither the AP nor the STA constitute a connection with the repeater.

Figure 4 shows the station leaving the AP range and entering the range of transponders on the WiFi network shown in Figure 1.

As shown in Figure 4, the station moves from the AP range towards the transponder. During the exercise, the signal strength of the AP becomes weak, and the transponder becomes stronger. The STA in motion continuously detects the signal strength of the AP and the repeater, such as the relative signal strength indicator (RSSI), using common techniques. When a certain standard of the detected signal strength is met, the connection C1 between the station and the AP will be disconnected, and the connection C2 between the station and the repeater and the connection C3 between the repeater and the AP will be established. For example, the above criteria will reach the threshold value when the signal strength of the transponder and the AP signal strength differ.

Figure 5 is a flow chart showing the procedure by which a station moves from the AP range into the repeater range. As shown in Figure 5, initially, the AP and SAT communicate in a normal mode, the AP range modal. The STA in motion continuously detects the signal strength of the AP and the repeater. Second, the STA compares the signal strength of the repeater and the AP to determine whether the phase difference is equal to or greater than a predetermined value. If the result is "No", it will remain in the normal state. Otherwise, the connection C1 is detached, the connection C2 is established, and then C3. Therefore, the STA communicates with the AP via the repeater, which represents the repeater range modality.

Figure 6 shows the station in the range of transponders on the WiFi network shown in Figure 1. As shown in Fig. 6, the AP component of the repeater has the same SSID (AP-SSID) as the associated AP. The station component of the repeater constitutes the same AMC address (MAC1) as the associated STA.

The MAC address configuration of the station component of the repeater can be static or dynamic. For static configuration, the user can enter the MAC address of the station through management definitions such as Command Line Interface (CLI), Network, Simple Network Management Protocol (SNMP), and so on. For dynamic configuration, the repeater automatically obtains the address of the station when it is connected to the station, and replaces the AMC address of the station component with the MAC address of the station.

The user can form an SSID through a management interface such as CLI, network, SNMP, and the like. Otherwise, you can use the existing standard WPA, Wi-Fi protection settings, for configuration.

Next, in detail, according to a specific example of the present invention, the station is a data stream between WiFi devices of the WiFi network in the case of the transponder.

Fig. 7 is a diagram showing an example of the data flow of the AP to the station in the case shown in Fig. 6.

According to a specific example of the present invention, since the MAC address of the repeater is the same as the MAC address of the STA, the entire frame that the AP deliberately sends to the station can be received by the repeater through the connection C3. If the frame is a management frame or a control frame, the repeater can be used as a terminator for such frames. If the frame is a data frame, if the protection flag is set in the 802.11 header, the repeater can decrypt the frame, change the BSSID of the frame to BSSID2, encode the frame, and send it to the station through the connection C2. .

Figure 8 shows the data flow from the station to the AP in the case shown in Figure 6.

As shown in Figure 8, all the frames transmitted by the station are received by the repeater via connection C2. The repeater acts as a terminator for managing the frame and controlling the frame. For the data frame, if the protection flag of the frame has been set, the transponder will decrypt the frame, change the BSSID to BSSID1, and encrypt the frame, and send it to the AP through the connection C3.

Figure 9 shows the station leaving the transponder range and entering the AP range on the WiFi network shown in Figure 1.

As shown in Figure 9, the station moves from the transponder range towards the AP. During the motion, the station continuously detects the signal strength of the AP and the repeater. When a certain standard of the above-mentioned detection signal level is met, the connection C2 between the station and the repeater, and the connection C3 between the repeater and the AP are separated, and the connection C1 between the station and the AP is established again. For example, the above criteria will differ between the signal strength of the AP and the signal strength of the transponder and will reach the threshold.

Figure 10 is a flow chart showing the procedure by which a station moves from the repeater range into the AP range. As shown in Figure 10, initially, the AP and STA communicate in a transponder-range modality. Then, the moving STA continuously detects the signal strength of the AP and the repeater. Second, the STA compares the signal strength of the AP and the repeater to determine whether the phase difference is equal to or greater than a predetermined value. If the result is "No", the repeater range mode is maintained. Otherwise, the connection C2 is detached, and then the connection C1 is connected again. Thereafter, the connection C3 is detached. Therefore, the communication returns to the AP range mode, where the STA communicates directly with the AP.

In many WiFi tile solutions, the STA sends an ACK to the AP after receiving the AMC address with the STA as the WiFi frame of the destination MAC address. When the station is in the 徘徊 area (the station can receive WiFi signals from both the AP and the repeater at this time). Figure 11 shows the problem when the station is in the area.

As described in FIG. 11, when the station operates in the transponder mode, an ACK is also sent for the WiFi frame, that is, the AP is intended to transmit to the repeater. There are three possible conditions for this situation as follows: (1) Both the station and the AP are connected to the frame, and the ACK is sent back to the AP; (2) only the station is connected to the frame, and the ACK is sent back to the AP; (3) only the repeater Receive the frame and send the ACK back to the AP. Obviously only the situation (3) is normal. Condition (1) will be confused and condition (2) will result in frame loss.

To solve this problem, a dual channel is proposed. Figure 12 shows the dual physical channel mode of the station in the zone of the AP and the repeater. As shown in Fig. 12, the AP component of the repeater operates on a physical channel different from the channel in which the AP is in use. In the transponder modality, the station operates on a different channel than the physical channel of the AP. In this case, the station can no longer receive any WiFi frames sent by the AP.

As described above, the WiFi repeater of the specific example of the present invention maintains the continuity of the link layer because the station component of the repeater has the same MAC address of the station. This is a useful improvement to the MAC disguise method, in which case the PPPoE continuity is broken due to changes in the MAC address.

Although specific examples have been presented on the WiFi network, it is known to those skilled in the art that the principles of the present invention can be applied to other wireless communication networks. It is to be understood that there are numerous modifications to the illustrative embodiments, and other configurations may be derived without departing from the spirit and scope of the invention as defined in the appended claims.

AP. . . Access point

C1, C2, C3. . . connection

MAC. . . Media access control layer

STA. . . hue

SSID. . . Service setting identifier

C4. . . Internal connection

1 is a diagram showing a WiFi network according to an embodiment of the present invention, having a station, an access point, and a repeater;

Figure 2 is a block diagram showing the structure of the repeater shown in Figure 1;

Figure 3 shows the station in the range of access points on the WiFi network shown in Figure 1;

Figure 4 shows the station leaving the range of access points on the WiFi network shown in Figure 1 and entering the range of the repeater;

Figure 5 shows the procedure for the station to move from the access point range into the repeater range;

Figure 6 shows the station in the range of the transponder on the WiFi network shown in Figure 1;

Figure 7 shows the data flow from the access point to the station in the case shown in Figure 6;

Figure 8 shows the data flow from the station to the access point in the case shown in Figure 6;

Figure 9 shows the situation where the station leaves the range of the repeater on the WiFi network shown in Figure 1 and enters the access point range;

Figure 10 shows the procedure for the station to enter the access point range from the repeater range;

Figure 11 shows the problem when the station is located in the squat area;

Fig. 12 shows a dual physical channel mode of a specific example of the present invention.

AP. . . Access point

C1, C2, C3. . . connection

MAC. . . Media access control layer

STA. . . hue

SSID. . . Service setting identifier

Claims (12)

A communication method on a wireless network having an access point (AP), a station (STA), and a repeater having the same network configuration parameters as an access point (AP), characterized in that The method is at the repeater level and includes the steps of: establishing a first communication channel (C2) with the station (STA); establishing a second communication channel (C3) with the access point (AP) to identify the MAC address of the station , replacing the MAC address used for communication with the access point (AP); and making data frames between the access point (AP) and the station (STA) via the first and second communication channels (C2) , C3) Correspondent. The method of claim 1, wherein the first communication channel (C2) is established in response to a signal strength of the repeater and the access point (AP). For example, in the method of claim 2, the first communication channel (C2) is established according to whether the difference between the transponder signal strength and the access point (AP) signal strength is greater than or equal to a predetermined value. The method of claim 3, and the method of deviating from the first and second communication channels (C2, C3) in response to the transponder and access point (AP) signal strength. The method of claim 4, wherein the first and second communication channels (C2, C3) are disconnected according to the difference between the access point (AP) signal strength and the transponder signal strength being greater than or equal to a predetermined value. The method of claim 1, wherein the network configuration parameter comprises a service setting identifier (SSID), a security method, and an external access point (AP). A wireless repeater, including an access point unit, and a station unit, connected to an access point via an internal connection (C4); the access point unit setting and an external access point (AP) have the same configuration parameters, and are suitable for establishing and The first wireless channel (C2) of the external station (STA), such that the data frames are between the station unit and the external station (STA) via the first wireless Channel (C2) and internal connection (C4) communication; the station unit is adapted to establish a second wireless channel (C3) such that the frame is between the station unit and the external access point (AP) via the second wireless channel (C3) Communication with internal connection (C4); characterized in that the station unit sets the same MAC address as the external station (STA) for the communication between the frame and the external access point (AP). For example, the wireless repeater of claim 7 wherein the MAC address is set using a command line interface, a network, or a simple network management protocol. For example, the wireless repeater of claim 7 wherein the configuration parameters include a service setting identifier (SSID), a security method, and an external access point (AP). For example, the wireless repeater of claim 9 wherein the configuration parameters are set using a command line interface, a network, or a simple network management protocol. For example, the wireless repeater of claim 9 of the patent scope, wherein the configuration parameters are set according to the WiFi protection access standard. For example, the wireless repeater of claim 7 of the patent scope, wherein the first communication channel (C2) and the wireless access channel used by the external access point (AP) to communicate with the external station are physically different.