CN1852192A - Network identifying method in wireless local network - Google Patents

Abstract

The invention discloses a method for network identification in a wireless local area network. The wireless local area network includes at least one basic service set constructed by a plurality of terminal devices and at least one extended service set to which it belongs; including the steps of: The set adopts the uniquely identified extended service set identification. When performing channel scanning, the extended service set identification parameter is added; when the terminal device accesses for the first time, the extended service set identification parameter is set as the media access control broadcast address; otherwise, set Identifies a specific extended service set; synchronizes to the corresponding extended service set during network selection, and uses the extended service set identification as a parameter to perform authentication and association with the network system. Since the method of the present invention sets a new extended service set identification for the identification identification of each terminal equipment and basic service set in different extended service sets, it can globally unify the identification, and satisfies the requirement of fast roaming of 802.11 terminals under the same ESS need.

Description

A method for network identification in wireless local area network

technical field

The invention relates to a network identification method, in particular to a network identification method in a wireless local area network.

Background technique

In the prior art, the WLAN (Wireless Local Area Network) technology is very popular in the market because of its wireless characteristics in networking, high-speed access comparable to wired connections, and its low price. At present, it has begun to replace wired and widely used in homes, campuses, hotels, corporate offices, etc., and has begun to be widely deployed in public places as a wireless broadband access technology to provide public wireless broadband data access services. ISO/IEC 8802-11: 1999 "Specific requirements for telecommunication and information exchange between information technology systems Local area network and metropolitan area network Part 11: Wireless LAN certain body access control (MAC, Media AccessControl address is the identification of the local area network node) and physical Layer (PHY) Specification" is an international standard for WLAN, and its content corresponds to the IEEE 802.11 standard.

China has also released the WLAN national standard GB/T 15629.11-2003, the main difference between it and the international standard lies in the security mechanism of access control. In fact, WLAN products widely used in the market are mainly the supplementary specifications for IEEE 802.11 released by the IEEE 802.11 standard project group, including IEEE802.11b, IEEE 802.11g, IEEE 802.11a, etc. Among them, 802.11b and 802.11g work in the 2.4Hz frequency band, and 802.11a work in the 5GHz frequency band. The physical layer rate supported by 802.11b can reach 11Mb/s, and the physical layer rate supported by 802.11g and 802.11a can reach 54Mb/s. At present, IEEE 802.11 is formulating a standard 802.11n that supports higher throughput to better support various real-time services and multimedia applications and increase system capacity.

According to the WLAN system defined by the IEEE 802.11 standard, its basic structure is shown in Figure 1. STA (Station) refers to a terminal device that includes an IEEE 802.11 wireless LAN interface. LAN interface. For some devices without a wireless LAN interface, a WLAN wireless network card can be installed to provide a wireless LAN interface.

As shown in Figure 1, AP (Access Point) is the access point, which is equivalent to the base station of the mobile network. Its main function is to enable each terminal device STA to communicate with other STAs or related devices of the wired network, for example: multiple STAs connected to an AP form a wireless LAN for communication, STAs connected to different APs form a LAN for communication, and STAs communicate with related devices in a wired LAN, and so on. The STAs associated to an AP constitute a basic service set (BSS).

Among them, DS (Distribution System) is the distribution system, so that different basic service sets BSS, and between BSS and wired LAN can form a large local area network, which is called extended service set ESS; where portal refers to the provision of DS and Logical point for forwarding of MAC Service Data Units (MSDUs) between wired LANs.

The 802.11 standard defines the service set identifier SSID, sometimes called ESSID, which is used to identify an extended service set ESS, that is, when BSSs are interconnected through DS to form an ESS, the SSID configured on each AP is the same. However, since the definition of SSID does not have a global encoding specification, even two completely independent and different networks may configure the same SSID. Therefore, in practical applications, even if the SSIDs configured by two BSSs are the same, Nor can it be determined that the two BSSs belong to the same ESS.

When a STA roams from one BSS to another within an ESS, since the SSID cannot be trusted to identify the ESS, it is virtually impossible to establish any relationship between the STA and the ESS; roaming across BSSs is equivalent to crossing two different physical networks, which leads to the complexity of re-establishing associations between STAs and new BSSs, especially security associations, such as the need for pre-authentication or re-authentication. Moreover, in the prior art, when selecting a target BSS before roaming, it is impossible to determine whether the target BSS and the current BSS belong to the same ESS.

Therefore, there are also defects in the prior art, which need to be improved and developed.

Contents of the invention

The purpose of the present invention is to provide a method for network identification in a wireless local area network. Corresponding to the extended service set ESS concept defined by the 802.11 standard, an ESS identification scheme is proposed, which can uniquely identify different ESSs and satisfy the requirements of 802.11 terminals in the same ESS. meet the needs of fast roaming.

To achieve the above object, technical solutions of the present invention include:

A method for network identification in a wireless local area network, wherein the wireless local area network is structured by a plurality of terminal devices, the plurality of terminal devices form at least one basic service set, and the basic service set forms at least one extended service set; Said method comprises steps:

A. Using a uniquely identified extended service set identifier for the extended service set, and adding the extended service set identifier parameter when performing channel scanning;

B. When the terminal device accesses for the first time, set its extended service set identification parameter to the media access control broadcast address; otherwise, set it to a specific extended service set identification;

C. When selecting a network, if the ESSI parameter of the terminal equipment is not the media access control broadcast address, then judge whether the corresponding channel belongs to the ESSA with the same ESSI ID as the terminal equipment, and if so, synchronize to the corresponding The extended service set, and use the extended service set identifier as a parameter to authenticate and associate with the network system.

Said method, wherein, said extended service set identifier is a media access control broadcast address corresponding to the extended service set.

The method described above, wherein, the extended service set is represented as an entry address corresponding to the extended service set communicating with the external network.

The method described above, wherein, the extended service set to which the basic service set belongs broadcasts its extended service set identifier by adding a domain extended service set in the 802.11 beacon frame.

The method described above, wherein when the basic service set belongs to multiple extended service sets, a list of extended service set identifiers is set in the domain extended service set.

The method further includes: adding the corresponding domain extended service set to carry its extended service set identifier in the response frame of channel scanning.

The method described above, wherein, when the response frame does not carry the ESID or the ESID is a broadcast address, the corresponding ESID is the ESID of the basic service set.

The method described above, wherein, the wireless local area network corresponds to a hierarchical structure according to the extended service set identifier, and the hierarchical structure includes: a basic service set level and an extended service set level; an authentication server connected to the two-level network , and perform identity authentication between each terminal device and the authentication server, negotiate a master key, and generate a corresponding extended service set domain key, and a basic service set domain key that is a session key.

The method described above, wherein the session key is generated according to the extended service set domain key, and the extended service set domain key is generated according to a master key negotiated between the terminal device and the authentication server.

A method for network identification in a wireless local area network provided by the present invention, since a new extended service set identification is set for the identification identification of each terminal device and basic service set in different extended service sets, the identification can be unified, and satisfy Meets the requirement for fast roaming of 802.11 terminals under the same ESS.

Description of drawings

FIG. 1 is a network architecture diagram specified in the 802.11 standard of the prior art;

Fig. 2 is a schematic diagram of the network architecture of the wireless local area network of the present invention;

Fig. 3 a is the flow chart of the passive scanning when the channel scanning of the method of the present invention;

Fig. 3 b is the flow chart of the active scanning when the channel scanning of the method of the present invention;

FIG. 4 is a schematic diagram of the network architecture of the wireless local area network of the method of the present invention.

Detailed ways

Various preferred embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings.

In the method for network identification in the wireless local area network of the present invention, it sets a new ESS mark: extended service set mark ESSID, the sign BSSID that the basic service set BSS of existing 802.11 standard definition adopts is the MAC address of AP . For ESS, SSID is used, which is different from BSSID. SSID is a character string. Currently, the only application is for users to distinguish different user groups or services on the same AP. Therefore, even if two BSSs are set with the same SSID, it does not mean that the two BSSs belong to the same ESS, and there is no global encoding method for SSIDs. Therefore, in the method of the present invention, a definition method similar to BSSID is adopted, and a MAC address is also used to identify an ESS, which is called ESSID. Because the MAC address has a globally unique identifier, different ESSs can be uniquely identified by the MAC address. In this way, different ESSs have different ESSIDs.

Specifically, in an ESS embodiment of the method of the present invention, its ESSID may be an entry address (Entrance Address) for intercommunication between the ESS and the external network. When the ESS is completely isolated, that is, not in contact with any external system, its ESSID can be set as the MAC broadcast address.

In a wireless local area network physical network in the method of the present invention, only one BSS may be included, or only one ESS may be included, or multiple ESSs may also be included. And the method of the present invention allows one BSS to belong to multiple ESSs at the same time, for example, when the local area network has multiple entrances to communicate with external networks. Due to the mobility of the terminal equipment in the wireless local area network, the structure of the wireless local area network is different from that of the wired local area network, and has certain flexibility. The flexible inclusion relationship between ESS and BSS is shown in Figure 2. BSS#1 and BSS#2 belong to both ESS#1 and ESS#2; BSS#1, BSS#2 and BSS#3 are the same Belongs to ESS#1, BSS#1, BSS#2 and BSS#4 belong to ESS#2.

The working principle of the method of the present invention includes: in ESSID-based network selection, there are the following situations for a STA to access a wireless local area network: 1) STA accesses for the first time and does not know the ESSID of the network; 2) STA requires access to a specific For example, in the case of roaming access, the STA has already connected to a specific ESS, but requires roaming from the current BSS to another BSS within the ESS.

The ESSID-based network selection method is to increase the parameter ESSID when performing channel scanning. When the STA accesses for the first time, set the ESSID as the MAC broadcast address; otherwise, set it as a specific ESSID, that is, the extended service set identifier to which it belongs. When the parameter ESSID is the broadcast address, the network selection depends on other parameters, which is the same as the prior art. When the parameter ESSID is not a broadcast address, only when the corresponding channel belongs to the ESS, that is, has the same ESSID as the terminal, it is allowed to synchronize to the corresponding ESS, and use the ESSID as a parameter to perform authentication and association with the system.

After adding the extended service set identifier ESSID in the wireless network of the method of the present invention, the ESSID to which the BSS belongs can be broadcast by adding the corresponding domain ESS in the 802.11 beacon (Beacon) frame. When a BSS belongs to multiple ESSs at the same time, the domain includes An ESSID list; at the same time, the 802.11 probe frame Probe Request can add the corresponding domain ESS to carry the ESSID to actively scan the BSS belonging to the corresponding ESS; as shown in Figure 3a and Figure 3b, IEEE 802.11 Probe Response adds the corresponding domain ESS to carry the ESSID, when When the Probe Request does not carry ESSID or ESSID is the broadcast address, the ESSID in this field is the ESSID to which the BSS belongs; or when the BSS belongs to the ESS corresponding to the ESSID carried by the Probe Request, the ESSID in this field is equal to the corresponding ESSID value in the Probe Request. The passive scan in the method of the present invention is initiated by the BSS to the STA, while the active scan is initiated by the STA.

After the ESSID is determined in the method of the present invention, the 802.11 authentication process and the association process can increase the ESSID parameter, so that the authentication process and the association process are associated with the ESS to facilitate its authentication. When the ESSID is a broadcast address or the field is empty, the above-mentioned relevant processing flow is the same as the original 802.11 standard.

After the parameter ESSID is set in the method of the present invention, the wireless local area network can be corresponding to a hierarchical security framework, which is divided into two levels in the wireless local area network: ESS level and BSS level; as shown in Figure 4, in the hardware network The BSS can cross-set the architecture ESS. An authentication server AS connects to the two-level hardware network. The terminal device STA communicates with the BSS through the session key PTK, communicates with the ESS through the ESS key, and connects with the master key for authentication. Server AS.

Based on this hierarchical structure, when a STA accesses the system for the first time, identity authentication is performed between the STA and the authentication server AS, the master key MSK is negotiated, and the corresponding ESS domain key is generated, and the BSS domain key is the session key PTK . The session key between STA and AP is generated based on the ESS domain key, and the ESS domain key (ESS KEY) is generated based on the master key negotiated between STA and AS. Therefore, when a STA roams between BSSs in an ESS, it only needs to renegotiate the session key, and does not need pre-authentication or re-authentication as described in 802.11i, which reduces the roaming process and realizes convenient and fast roaming communication.

In the hierarchical structure of the present invention mentioned above, within the life cycle of MSK, regular update of ESS KEY can be performed, and within the life cycle of ESS KEY, regular update of PTK is allowed. The definition of PTK and MSK is corresponding to the definition of PTK and MSK of IEEE 802.11i, the only difference is that the PTK of 802.11i is generated according to MSK, while the PTK in the method of the present invention is generated according to ESS KEY.

Each key of the method of the present invention represents the trust relationship between the negotiating parties, and it should be noted that the above schematic diagram only shows the basic structure of the method system of the present invention. In practical applications, if the authentication server may Other connection levels can be added with the hierarchical network, and these are obviously also within the scope of the technical concept of the present invention.

The method of the present invention corresponds to the ESS concept defined by 802.11, and provides an ESS identification scheme, that is, setting a new parameter ESSID, using the global unique identification parameter of the MAC address, can uniquely identify different ESSs, and meets the requirements of 802.11 The terminal needs to roam quickly under the same ESS.

The method of the present invention can perform network selection based on the unique identifier, and correspond the security mechanism to a hierarchical structure, increase the ESS-KEY, avoid the pre-authentication or re-authentication required by 802.11i when roaming across BSSs in the ESS, and realize roaming more fast.

It should be understood that the above descriptions for specific embodiments are relatively specific, and should not be considered as limiting the scope of the patent protection of the present invention, and the scope of protection of the patent of the present invention should be determined by the appended claims.

Claims (9)

1, the method for Network Recognition in a kind of WLAN (wireless local area network), described WLAN (wireless local area network) comprise that a plurality of terminal equipment frameworks form, and described a plurality of terminal equipments are formed at least one Basic Service Set, and described Basic Service Set is formed at least one extended service set again; Described method comprises step:

A, described extended service set is adopted the uniquely identified extended service set identification, when carrying out scan channel, increase this extended service set identification parameter;

B, when terminal equipment inserts for the first time, its extended service set identification parameter is set to media interviews control broadcast address; Otherwise, be set to specific extended service set identification;

If C, the extended service set identification parameter of described terminal equipment is not media interviews control broadcast address when network selecting, judge then whether respective channels belongs to the extended service set with the identical extended service set identification of this terminal equipment, then be synchronized to corresponding extended service set in this way, and be that parameter is carried out authentication and related with network system with this extended service set identification.

2, method according to claim 1 is characterized in that, described extended service set identification is the media interviews control broadcast address of corresponding extended service set.

3, method according to claim 1 is characterized in that, described extended service set identification is the entry address of corresponding extended service set and external network intercommunication.

4, method according to claim 1 is characterized in that, the extended service set under the described Basic Service Set is broadcasted its extended service set identification by increasing the territory extended service set in 802.11 beacon frames.

5, method according to claim 4 is characterized in that, when described Basic Service Set belongs to a plurality of extended service set, the tabulation of an extended service set identification is set at described territory extended service set.

6, method according to claim 1 is characterized in that, also comprises: increase the corresponding field extended service set and carry its extended service set identification in the acknowledgement frame of scan channel.

7, method according to claim 6 is characterized in that, does not carry extended service set identification or extended service set identification in the described acknowledgement frame when being broadcast address, and the corresponding domain extended service set identification is the extended service set identification of this Basic Service Set.

8, method according to claim 1 is characterized in that, described WLAN (wireless local area network) corresponds to one deck level framework according to described extended service set identification, and this level framework comprises: a Basic Service Set level and an extended service set level; One authentication server connects this two-level network, and carries out authentication between each terminal equipment and the authentication server, consult master key, and generate corresponding extended service set domain key, and the Basic Service Set domain key is a session key.

9, method according to claim 8 is characterized in that, described session key generates according to described extended service set domain key, and described extended service set domain key generates according to the master key of consulting between described terminal equipment and the authentication server.

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