KR20080083089A - Communication method for wireless network, access point and station for wireless network system - Google Patents

Abstract

A communication method in a wireless network, an AP(Access Point) in a wireless network system, and a station therein are provided to enable a station, connected with an AP of a WISP(Wireless Internet Service provider) which doesn't support an emergency call service, to request an emergency call to a PSAP(Public Safe Answering Point) as an AP, which broadcasts an emergency notification frame in case an emergency situation occurs, converts the BSSID(Basic Service Set Identifier) of the emergency notification frame into a broadcast BSSID. The first AP is an AP of the first WISP which supports an emergency call service, and the second AP is an AP of the second WISP which doesn't support the emergency call service. The first STA(Station), which belongs to both the first BSS(Basic Service Set) and the second BSS, is connected to the second AP. The second STA, which belongs to the first BSS only, is connected to the first AP. If an emergency situation occurs, a PSAP which provides the emergency call service informs the first AP of it. Notified that the emergency situation has occurred, the first AP broadcasts data containing an emergency notification. In this case, the first AP formats the data into an emergency notification frame. Also the first AP formats the BSSID of the emergency notification frame into a broadcast BSSID so that the first STA connected with the second AP can receive the data without filtering. Accordingly the first STA can acquire the information contained in the frame body of the received emergency notification frame. The first STA accesses the first AP through the SSID of the first AP contained in the emergency notification frame according to a connection procedure, and requests an emergency call to the PSAP.

Description

Communication method in wireless network, access point and station in wireless network system {Communication Method for Wireless Network, Access Point and Station for Wireless Network System}

1A and 1B are conceptual diagrams of wireless network systems in which an embodiment of the present invention is performed;

FIG. 2 is a flowchart illustrating a coupling process for data transmission in the WLAN system of FIG. 1A; FIG.

3 is a format of an interworking capability information element added to a beacon frame of IEEE 802.11.

FIG. 4 is an interworking capability field of FIG. 3; FIG.

5 is a flow diagram of emergency broadcast call support in one embodiment of the present invention.

6 is an "emergency notification frame" in accordance with an embodiment of the present invention.

FIG. 7 is a frame body of the " emergency notification frame " of FIG.

<Description of the symbols for the main parts of the drawings>

10: WLAN system

12: station

14: access point

16: distribution system

The present invention relates to a communication method for transmitting and receiving various information or data related to an emergency call in a wireless network, and a wireless network system thereof.

Disasters such as the 911 terrorism in the United States and the tsunami in Thailand have raised interest in emergency calls.

In order to support emergency calls, it must be possible for a mobile station to use wireless network resources without authentication.

An object of the present invention is to transmit and receive various information or data related to an emergency call in an wireless network.

Technical problems to be achieved by the present invention are not limited to the above-mentioned technical problems, and other technical problems not mentioned above may be clearly understood by those skilled in the art from the following description. There will be.

According to one aspect, the present invention, the access point transmits data containing the emergency notification (emergency notification). In addition, at least one station does or does not receive data, and if the station receives data, it does or does not perform an emergency call according to the data.

According to another aspect, the present invention includes an access point for transmitting data that includes an emergency notification. It also includes a station that does or does not receive data, and does or does not perform an emergency call according to the data when the data is received.

In another aspect, the present invention transmits data that includes an emergency notification to at least one station. In this case, when the station requests an emergency call according to the data, the station makes an emergency call.

In addition, the present invention does not receive or receive data including an emergency notification transmitted by the access point, and when receiving the data, does not perform or perform an emergency call according to the data. Does not.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings. Hereinafter, an embodiment of the present invention will be described with an example of a wireless LAN system of the wireless network system. However, one embodiment of the present invention will be substantially the same as the WLAN system in the same or allowable range in the range allowed or supported in various wireless network systems other than the WLAN system. In addition, the terms or words used in the following embodiments of the present invention may be used as other terms or words in various wireless network systems. It is included in the scope of the invention.

First, a general wireless network system in which an embodiment of the present invention is performed and a general connection procedure of a wireless network system in which an embodiment of the present invention are performed will be described.

Wireless Network System

1A and 1B are conceptual diagrams of wireless network systems in which an embodiment of the present invention is performed. Like elements in FIGS. 1A and 1B use the same reference numbers.

Referring to FIG. 1A, a wireless network system, for example, a wireless LAN system 10 may include a plurality of stations or stations 12, an access point or a wireless base station 14, a backbone network or a distribution system ( 16).

A plurality of stations 12 is equipped with a wireless LAN network interface card (Network Interface Card) to perform the operation of the physical layer and MAC layer based on the IEEE 802.11 standard. In the WLAN system 10 shown in FIG. 1A, a plurality of stations 12 are coupled to an access point 14 to transmit data frames.

The access point 14 performs a wired / wireless interworking bridge function of relaying a frame transmitted from one station to another station. This access point 14 performs the same function as a bridge or switch of Ethernet.

In addition, since the access point 14 includes a physical layer and a MAC layer that are basically the same as the station 12 described above, the access point 14 basically performs the same operation as the station 12. Can be. Thus, the access point 14 may be considered the same as the station 14 as needed.

The distribution system 16 is a backbone network connecting several access points 14. The distribution system 16 is generally Ethernet, but can also connect several access points 14 wirelessly. Broadly speaking, the distribution system 16 may include routers or switches connected to Ethernet and servers connected to wired and wireless Internet networks.

Referring to FIG. 1B, a wireless network system, for example, a wireless LAN system 10 includes a plurality of stations or terminals 12. The WLAN system 10 is directly connected point-to-point between a plurality of stations 12. Thus, unlike FIG. 1A, in the WLAN system 10 illustrated in FIG. 1B, a separate access point 14 or a distribution system 16 does not exist, and a plurality of stations 12 may replace their role or some of them. Roles or functions may be omitted.

Although the WLAN system 10 has been described with reference to FIGS. 1A and 1B, a wireless network system including a WLAN system 10 according to an exemplary embodiment of the present invention is not limited thereto, and a combination or a completely different one thereof. It can be implemented as a system. In addition, the wireless network system according to an embodiment of the present invention may exist alone, but may interwork with another wireless network system, a mobile communication network, or a wired / wireless internet network.

For example, the WLAN system may provide roaming service by interworking with a mobile communication network, for example, Wideband Code Division Multiple Access (WCDMA). Specifically, when the WLAN system provides a voice service, a dual band dual mode (DBDM) terminal supporting both WLAN and WCDMA performs a voice call using a mobile communication network, and then supports the WLAN system. In the WLAN system can be automatically roaming seamlessly.

Whether the wireless LAN system 10 shown in FIG. 1A or the wireless LAN system 10 shown in FIG. 1B is transmitted between stations 12 or via a coupling process between the station 12 and the access point 14 to transmit data. Can be.

Connection Procedure

FIG. 2 is a flowchart illustrating a coupling process for data transmission in the WLAN system of FIG. 1A. Although the WLAN system of FIG. 1B and the various wireless network systems described above are partially different from those of FIG. 2, the detailed description is omitted since it includes a combining process for transmitting substantially the same data.

1A and 2, the combining process 20 for data transmission between the station 12 and the access point 14 in the WLAN system 10 includes a scanning process (S10) and an authentication process (Authenticaion). , S12), and association (S14). The station 12 and the access point 14 perform a data transmission process S16 via the above processes S10, S12, S14.

Scanning (S10) is a process of finding a neighboring access point 14 using a beacon or probe message.

The discovery process S10 may include passive scanning to find the access point 14 from a beacon message broadcast by the access point 14 periodically, and the station 12 requests a probe for each channel. Broadcasts a message or frame (Probe Request), receives the received probe response message (Probe Response) such as its SSID (Service Set ID) and operation speed from the access point 14 to select the corresponding access point (14) It includes an active search process. The beacon message stores various capabilities (speed, encryption, etc.) that the access point 14 can support, and an SSID (Service Set ID) which is a service group name to which the access point 14 belongs.

The authentication process (Authenticaion, S12) is a process for the station 12 that has selected the appropriate access point 14 by the discovery process (S10) to prove that it is a valid terminal for the access point (14). That is, the authentication process (Authenticaion, S12) is a process of negotiating the authentication procedure and the encryption method with the access point 14. In most cases, since the Open System authentication method is used, the access point 14 authenticates the authentication request from the station unconditionally. Enhanced authentication methods include IEEE 802.1x-based EAP-TLS, EAP-TTLS, EAP-FAST, and PEAP.

Association (S14) is a process in which the station 12 accesses the access point 14 after successful authentication. The connection process S14 means establishing an identifiable connection between the station 12 and the access point 14. When the connection process S14 is completed, the station 12 may communicate with another station 14 via the access point 14.

The association process S14 stores an AID (Association ID) that allows the access point 14 to be distinguished from other stations when the station 12 sends an association request message or frame to the access point 14. This is done by sending an Association Response message.

The station 12 and the access point 14 perform a data transmission process S16 via the above processes S10, S12, S14.

Emergency  Call ( emergency call )

FIG. 3 shows an interworking capability information element format added to a beacon frame of IEEE 802.11, and FIG. 4 shows the interworking capability field of FIG. Indicates.

Using the Emergency Service Only bit of FIG. 4, a corresponding Service Set Identifier (SSID) may support an Emergency Call Service.

In this case, the emergency call only supports one-to-one connection from the mobile station to the public safety answering point (PSAP). But mobile stations need to be aware of emergency situations.

5 illustrates a flow diagram of emergency broadcast call support in one embodiment of the present invention.

Referring to FIG. 5, access point 1 (AP 1) is an access point 14 of a wireless internet service provider (WISP) supporting an emergency call, and access point 2 (AP 2) is an emergency call. access point 14 of a wireless Internet service provider (WISP) that does not support an emergency call.

When an emergency occurs, a public safety answering point (PSAP) that serves an emergency call is an access point that is an access point of a wireless Internet service provider (WISP) that supports an emergency call. Inform the emergency situation at Point 1 (AP 1). The communication scheme from the public safety response point (PSAP) to the access point is outside the scope of one embodiment of the present invention.

Referring to FIG. 5, station 1 (STA 1) is a station 12 superimposed on BSS 1 (Basic Service Set 1) and BSS 2 (Basic Service Set 2). Station 2 (STA 2) is a station 12 belonging only to BSS 2 (Basic Service Set 2). Station 1 (STA 1) is connected to access point 2 (AP 2), and station 2 (STA 1) is connected to access point 1 (AP 1). Although only two stations STA 1 and STA 2 are shown in FIG. 5, there may be more stations 12.

Referring to FIG. 5, an access point 1 (AP 1) receiving an emergency situation broadcasts data including an emergency notification.

At this time, the access point 1 (AP 1) formats and transmits this data into an "emergency notification frame". Meanwhile, an "emergency notification frame" corresponds to a management frame.

6 illustrates an "emergency notification management frame" in accordance with an embodiment of the present invention.

Referring to FIG. 6, an "emergency notification management frame" corresponds to a management frame. The management frame includes a frame control, a basic service set identifier (BSSID), a frame body, and the like. In the case of an 802.11 management frame, the type of the frame control is "00", and the subtype is composed of 4 bits, of which "0110-0111" and " 1110-1111 "is not yet used.

Therefore, since an "emergency notification frame" corresponds to a management frame, "00" is used as a type of frame control, and frame control is performed. ), Any one of "0110", "0111", "1110" and "1111" is used. The type of frame control is to distinguish whether the frame control is a control frame, a management frame, or a data frame. The subtype of the frame control is to distinguish the type of detailed frames for each type of frame.

 Since an "emergency notification frame" corresponds to a management frame, it includes a basic service set identifier (BSSID). The BSSID ("emergency notification frame") of the "emergency notification frame" includes a BSSID ( Basic Service Set identifier) is a "broadcast BSSID" (broadcast Basic Service Set identifier).

The Basic Service Set Identifier (BSSID) represents the access point's medium access control (MAC) address, which is a "broadcast" such as a beacon or probe requesy described in the connection procedure shown in Figure 2. A frame that uses a "broadcast basic service set identifier (BSID)" is not subjected to any broadcast basic service set identifier filtering (BSSID) in medium access control (MAC). The use of broadcast Basic Service Set Identifiers (BSSIDs) for "emergency notification frames" also applies BSSID filtering in medium access control (MAC) of stations STA 1, STA 2, ... Service Set identifier filtering).

FIG. 7 shows a frame body of the " emergency notification frame " of FIG.

Referring to FIG. 7, a frame body of an "emergency notification frame" includes an emergency category, a service set identifier (SSID), and a location of emergency. Emergency notifications, etc.). The location of emergency may use the location data and location descriptor of IEEE 802.11v as it is.

The Emergency Category indicates the type of emergency, such as tsunami, riot, and war, and the Service Set Identifier (SSID) indicates the type of access point that transmits the "emergency notification frame." Represents a service set identifier (SSID), and a location of emergency indicates a location where an emergency occurs.

Therefore, in one embodiment of the present invention, since the access point 14 transmitting the "emergency notification frame" is access point 1 (AP 1), the "emergency notification frame" The Service Set Identifier (SSID) of the frame body of "frame" is the Service Set Identifier (SSID) of Access Point 1 (AP 1).

Referring back to FIG. 5, station 1 (STA 1) is connected with access point 2 (AP 2). Thus, if the basic service set identifier (BSSID) of the "emergency notification frame" is not the "broadcast basic service set identifier", station 1 (STA 1) is an access point in the normal case. It will not receive the data because 1 (AP 1) will filter the data it sends.

However, Access Point 1 (AP 1) formats the data into an "emergency notification frame", but the BSSID (Basic Notification Frame) of the "emergency notification frame" Since the service set identifier is formatted as a "broadcast basic service set identifier", the station 1 (STA 1) receives the data without filtering. Therefore, the station 1 (STA 1) is received. ) May obtain information included in the frame body of the received "emergency notification frame."

On the other hand, referring to Figure 7, the frame body of the "emergency notification frame (emergency notification frame) received by the station 1 (STA 1) is the SSID (Service Set) of the access point 1 (AP 1) Station 1 (STA 1) breaks association with Access Point 2 (AP 2) if necessary and uses the Service Set Identifier (SSID) of Access Point 1 (AP 1) as shown in FIG. By combining with Access Point 1 (AP 1) by a connection procedure, an emergency call may be requested from the Public Safety Response Point (PSAP).

That is, a station 1 (STA 1) that transmits an "emergency notification frame" to a station 1 (STA 1) is a wireless Internet service provider that supports an emergency call (Wireless Internet Service). Station 1 is a station of the provider, and the "emergency notification frame" received by the station 1 (STA 1) includes the service set identifier (SSID) of the access point 1 (AP 1). (STA 1), if necessary by using the SSID (Service Set identifier) of the access point 1 (AP 1) by combining with the access point 1 (AP 1) by the connection procedure shown in Figure 2 (public safety response) You can request an emergency call from a public safety answering point.

Meanwhile, referring back to FIG. 5, station 2 (STA 2) is connected to access point 1 (AP 1). Thus, regardless of whether the Basic Service Set identifier (BSSID) of the "Emergency Notification Frame" is a "broadcast Basic Service Set identifier" or not, Station 2 (STA 2) is the access point. The data is received since 1 (AP 1) will not filter the data it transmits.

Accordingly, the station 2 (STA 2) receiving the data, unlike the station 1 (STA 1), exits the public safety response point (PSAP) through the access point 1 (AP 1) without breaking the current association. You can request an emergency call.

Meanwhile, in the embodiment of the present invention, since station 2 (STA 2) is coupled to access point 1 (AP 1), an "emergency notification frame" received from access point 1 (AP 1). Regardless of whether the Basic Service Set identifier (BSSID) of the BBSID is a " broadcast Basic Service Set identifier (BSSS) ", the " emergency notification frame " Emergency call to the public safety response point (PSAP) via access point 1 (AP 1) regardless of whether the frame body of "contains the service set identifier (SSID) of access point 1 (AP 1). You can request an emergency call.

In one embodiment of the present invention, station 1 (STA 1) is an "emergency" from access point 1 (AP 1), even if the access point 2 (AP 2) to which it is joining does not support an emergency call. Receive an emergency notification frame and, if necessary, break the association with Access Point 2 (AP 2), and call an Emergency Call to the Public Safety Response Point (PSAP) through Access Point 1 (AP 1). so that STA 1 does not need to make any effort to recognize the emergency situation, and it does not need to make an emergency call. You do not have to make any effort to find an access point that supports calls, even if the access point 2 (AP 2) is an access point of a wireless Internet service provider (WISP) that you do not subscribe to. Since the "emergency notification frame" includes the Service Set Identifier (SSID) of Access Point 2 (AP 2), it requests an emergency call through Access Point 2 (AP 2). It becomes possible.

Meanwhile, some of the current access points are able to set several service set identifiers (SSIDs). This is to apply an independent communication policy for each service set identifier (SSID). At this time, if an emergency call is supported for multiple service set identifiers (SSIDs) for one access point, the radio resources of the access point are wasted.

Although one embodiment of the present invention has been described above with reference to the drawings, the present invention is not limited thereto.

In the above embodiments, reference has been made to IEEE 801.11 and IEEE 801.11e, etc., but the present invention is not limited to these standards.

In the above embodiments, a station for performing operations of the physical layer and the MAC layer based on the IEEE 802.11 standard by mounting a network interface card for a wireless LAN, and relaying a frame transmitted from one station to another station Although the access point performing the wired / wireless interworking bridge function has been described as an example, the present invention is not limited thereto.

In addition, since the access point basically includes the same physical layer and MAC layer as the station described above, the access point can basically perform the same operation as the station. Thus, the access point may be considered to be the same as the station as needed.

In the above embodiments, the WLAN system has been described as an example, but the present invention includes a wireless network system including a WLAN system, and a combination thereof or a completely different system may be implemented. In addition, although the wireless network system may exist alone, the present invention may interwork with other wireless network systems, mobile communication networks, and wired and wireless Internet networks.

For example, the WLAN system may provide roaming service by interworking with a mobile communication network, for example, Wideband Code Division Multiple Access (WCDMA). Specifically, when the WLAN system provides a voice service, a dual band dual mode (DBDM) terminal supporting both WLAN and WCDMA performs a voice call using a mobile communication network, and then supports the WLAN system. In the WLAN system can be automatically roaming seamlessly.

In the above embodiments, the basic service set identifier (BSSID) of the "emergency notification frame" transmitted by the access point 1 (AP 1) is a broadcast broadcast basic service set identifier (BSSID) However, in another embodiment, the basic service set identifier (BSSID) of the "emergency notification frame" may not be a broadcast broadcast basic service set identifier (BSSID). In this case, the station 1 (STA 1) coupled to the access point 2 (AP 2) can filter the "emergency notification frame" transmitted by the access point 1 (AP 1) to be received. none.

In the above embodiments, it is assumed that the "emergency notification frame" transmitted by the access point 1 (AP 1) includes the service set identifier (SSID) of the access point 1 (AP 1). The service set identifier (SSID) of the access point 1 (AP 1) may not be included. In this case, since the station 1 (STA 1) does not know the service set identifier (SSID) of the access point 1 (AP 1), as shown in the combining procedure shown in Figure 2 including the access point 1 (AP 1) A probe request message must be sent to another access point that supports an emergency call.

In the above embodiments, the "emergency notification frame" transmitted by the AP 1 (AP 1) is to include an emergency category, but the emergency category (emergency category) Instead, it can only contain information that an emergency has occurred.

In the above embodiments, the "emergency notification frame" transmitted by the access point 1 (AP 1) is to include a location of emergency (Location of emergency), but in other embodiments May not be included.

In the above embodiments, the "emergency notification frame" transmitted by the access point 1 (AP 1) is assumed to correspond to the management frame, but the frame of the data frame (data frame) The body may also include emergency notifications.

In the above description of the preferred embodiment of the present invention, the present invention is not limited to the above-described specific embodiment, it is common in the art to which the invention belongs without departing from the spirit of the invention claimed in the claims. Various modifications can be made by those skilled in the art, and such changes are within the scope of the claims.

The present invention has the effect of transmitting and receiving a variety of information or data related to the emergency in a wireless network.

Claims (25)

The access point transmitting data including emergency notifications; At least one station receiving or not receiving the data, and when the station receives the data, performing or not executing an emergency call according to the data. The method of claim 1, The emergency notification includes a service set identifier (SSID) of the access point. The method of claim 2, The emergency notification (emergency notification) is a communication method in a wireless network, characterized in that it comprises a location where the emergency (emergency) occurred. The method of claim 2, And said data is in a management frame format. The method of claim 4, wherein And a basic service set identifier (BSSID) of the management frame is a broadcast broadcast basic service set identifier (BSSID). Transmitting data including emergency notifications to at least one station; If the station requests an Emergency Call according to the data, causing the station to perform the Emergency Call. The method of claim 6, And the emergency notification includes an SSID (Service Set Identifier) of the access point. The method of claim 7, wherein The emergency notification (emergency notification) comprises a location where the occurrence of the emergency (emergency) communication method of the access point in a wireless network. The method of claim 7, wherein And said data is in a management frame format. The method of claim 9, And a basic service set identifier (BSSID) of the management frame is a broadcast broadcast basic service set identifier (BSSID). Receiving or not receiving data including an emergency notification sent by the access point; And when the data is received, performing or not performing an emergency call according to the data. The method of claim 11, And the emergency notification includes a service set identifier (SSID) of the access point. The method of claim 12, The emergency notification (emergency notification) comprises the location of the occurrence of the emergency (emergency) communication method of a station in a wireless network. The method of claim 12, And said data is in a management frame format. The method of claim 14, And a basic service set identifier (BSSID) of the management frame is a broadcast broadcast basic service set identifier (BSSID). Transmit data including emergency notification to at least one station, An access point in a wireless network system for causing the station to perform an emergency call when the station requests an emergency call according to the data. The method of claim 16, The emergency notification (emergency notification) includes a service set identifier (SSID) of the access point, the access point in a wireless network system. The method of claim 17, The emergency notification (emergency notification) comprises a location in which the emergency (emergency), the access point in a wireless network system. The method of claim 17, And said data is in a management frame format. The method of claim 19, The basic service set identifier (BSSID) of the management frame (management frame) is a broadcast broadcast basic service set identifier (BSSID), characterized in that the access point in a wireless network system. Receives or does not receive data that includes an emergency notification sent by the access point, A station in a wireless network system that does or does not perform an emergency call according to the data when the data is received. The method of claim 21, The emergency notification includes a service set identifier (SSID) of the access point. The method of claim 22, The emergency notification is a station in a wireless network system, characterized in that it comprises a location where the emergency (emergency) occurred. The method of claim 22, And the data is a management frame format. The method of claim 24, The basic service set identifier (BSSID) of the management frame (management frame) is a station in a wireless network system, characterized in that the broadcast broadcast basic service set identifier (BSSID).

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