WO2012151905A1

WO2012151905A1 - Method and device for network handover

Info

Publication number: WO2012151905A1
Application number: PCT/CN2011/082329
Authority: WO
Inventors: 岳晓贫
Original assignee: 中兴通讯股份有限公司
Priority date: 2011-09-01
Filing date: 2011-11-17
Publication date: 2012-11-15
Also published as: CN102970680A

Abstract

Disclosed are a method and device for a network handover. The method comprises: when a terminal is associated to a current network, performing an identity pre-authentication with a target network detected; when the identity pre-authentication is successful, and when a preset condition is met, the terminal handing over directly to the target network. The technical solution of the present invention solves the problem in the prior art of the network handover requiring extended period of time and resulting in the handover leading easily to network access discontinuity, thus allowing for effects of reduced handover time and eliminated handover-led network intermittence.

Description

TECHNICAL FIELD The present invention relates to the field of communications, and in particular to a network switching method and apparatus. BACKGROUND OF THE INVENTION A method for switching between a WLAN (Wireless Local Area Networks) network and a non-WLAN network has a long network switching time and a low handover success rate, and the handover is likely to cause network access discontinuity. The WLAN network browses the webpage. If the WLAN network signal strength is low and needs to be switched to the non-WLAN network, the terminal needs to disconnect the WLAN network, and after the non-WLAN network is authenticated and associated, the terminal can continue to browse the webpage; currently browsing the webpage through the non-WLAN network. If a WLAN network signal needs to be switched to the WLAN network, the terminal needs to disconnect the non-WLAN network and authenticate and associate the WLAN network before continuing to browse the webpage. Problems like this are common in the network switching process of terminals, and no effective solution has been proposed yet. SUMMARY OF THE INVENTION The present invention provides a network switching method and apparatus to solve at least one of the above problems. According to an aspect of the present invention, a network switching method is provided, including: performing pre-identification authentication with a detected target network after the terminal is associated with the current network; and after the pre-identification is successful, the terminal directly Switch to the target network. The above current network includes one of the following: a WLAN network, a non-WLAN network; the above target network includes one of the following: a WLAN network, a non-WLAN network. The terminal performs pre-authentication with the target network, including: The terminal invokes SIM (Subscriber Identity)

The authentication information in the Module (User Identification Module) or USIM (Universal Subscriber Identity Module) establishes the identity authentication process between the terminal and the target network through the current network. When the current network is a WLAN network and the target network is a non-WLAN network, the terminal invokes the authentication information in the SIM or the USIM to establish an identity authentication process between the terminal and the target network through the current network, including: the terminal and the non-WLAN network are connected to the WLAN network through the terminal. The AP (Access Point, access point) passes the authentication information; the AP and the non-WLAN network pass the authentication server of the non-WLAN network and the RADIUS (Remote Authentication Dial In User Service) authentication service of the WLAN network. The wired network between the devices transmits key information, wherein the encryption mode of the key information follows a transmission protocol of the SIM authentication within the WLAN network. The preset condition includes at least one of the following: a signal strength of the WLAN network is lower than a preset threshold, a frame error rate of data transmission between the terminal and the WLAN network is higher than a preset threshold, and a signal noise of data transmission between the terminal and the WLAN network A non-WLAN network is detected below the preset threshold. When the current network is a non-WLAN network and the target network is a WLAN network, the terminal invokes the authentication information in the SIM or the USIM to establish an identity authentication process between the terminal and the target network through the current network, including: the terminal and the WLAN network are transmitted through the authentication server of the non-WLAN network. Authentication information; the non-WLAN network and the WLAN network transmit key information through a wired network between the authentication server of the non-WLAN network and the RADIUS authentication server of the WLAN network, and the RADIUS authentication server transmits the key information to the RADIUS authentication server. The associated AP, wherein the key information encryption mode follows the SIM authentication transmission protocol of the non-WLAN network and the WLAN network. The preset condition includes at least one of the following: a WLAN network is detected, and a signal strength of the detected WLAN network is greater than a preset threshold. The foregoing authentication information includes: a source code for generating an authentication key, a framing detail of a key frame, a check of a key frame, and a integrity of the key; the key information includes: an encryption mode and an authentication encrypted using the encryption mode Information, wherein the encryption mode includes at least one of the following: non-encrypted mode, RC4 encryption method in WEP (Wired Equivalent Privacy) protocol, WPA (Wi-Fi Protected Access) protocol TKIP (Temporal Key Integrity Protocol) encryption method, AES (Advanced Encryption Standard) encryption method in WPA2 protocol, WAPI (Wireless LAN Authentication and Privacy Infrastructure) WPI (WLAN privacy infrastructure) - SMS4 (Packet Encryption Algorithm) encryption method. According to another aspect of the present invention, a network switching apparatus is provided, located on a terminal, including: a pre-authentication module, configured to perform pre-identification with the detected target network after the terminal is associated with the current network; , set to switch the terminal directly to the target network when the pre-conditions are met after the pre-authentication is successful. The current network includes one of the following: a WLAN network, a non-WLAN network; the foregoing target network includes one of the following: a WLAN network, a non-WLAN network. The present invention solves the prior art by adopting a scheme in which a terminal performs pre-identification with a detected target network that may become a handover target after being associated with the current network, and directly switches to the target network after the preset condition is satisfied. The problem that the network switching time is long and the handover is easy to cause network access discontinuity, thereby reducing the switching time and eliminating the network interruption caused by the handover. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are set to illustrate,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, 1 is a flowchart of a network switching method according to an embodiment of the present invention; FIG. 2 is a functional structural diagram of a terminal according to an example of the present invention; FIG. 3 is a WLAN network switching to a non-WLAN network according to an example of the present invention; FIG. 4 is a schematic diagram of a pre-authentication key sharing invocation procedure of a WLAN network switching to a non-WLAN network according to an example of the present invention; FIG. 5 is a schematic diagram of a process of switching a non-WLAN network to a WLAN network according to an example of the present invention; 6 is a schematic diagram of a pre-authentication key invocation procedure of a non-WLAN network switching to a WLAN network according to an example of the present invention; FIG. 7 is a structural block diagram of a network switching apparatus according to an embodiment of the present invention. BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the embodiments in the present application and the features in the embodiments may be combined with each other without conflict. 1 is a flow chart of a network switching method according to an embodiment of the present invention. As shown in FIG. 1 , the network switching method according to the embodiment of the present invention includes: Step S102: After the terminal is associated with the current network, perform pre-identification authentication with the detected target network. Step S104: After the pre-identification authentication succeeds, the terminal is pre- When the condition is met, switch directly to the target network. Preferably, the current network includes one of the following: a WLAN network, a non-WLAN network; the foregoing target network includes one of the following: a WLAN network, a non-WLAN network. Pre-authentication is a way to speed up association transfers. From the workstation to the new access point, to the new access point to start transmitting frames to the workstation, authentication is the most likely delay in this period of time, the purpose of pre-authentication is to shorten this time, before the need This time-consuming operation establishes a mutual authentication relationship. The workstation must be authenticated before being associated with the access point, but the 802.11 standard, a commonly used wireless LAN standard, does not require an immediate association after low-level authentication. During the scanning phase, the workstation can perform 802.11 authentication with several access points, so that association operations can be performed immediately when needed. This is called pre-authentication. The benefit of pre-authentication is that once access to the coverage of the access point, the workstation can immediately re-associate with the access point without having to wait for the authentication exchange process. The pre-authentication is mainly performed between the APs of the WLAN network. The current access point AP that has established a security association with the STA (Site) interacts with the destination AP after receiving the pre-authentication data sent by the STA. The mutual authentication of the certificate. If the verification result of the certificate of the destination AP is valid, the current AP sends the key information of the security association associated with the STA to the destination AP. The destination AP stores the key information, and the key information includes The STA negotiates the generated base key with the current AP. The method provided in this embodiment fully utilizes the idea of pre-authentication in the foregoing pre-authentication mechanism, and creatively applies it to the process of switching between a WLAN network and a non-WLAN network, that is, the terminal is switched from the WLAN network to the non-WLAN. The process of switching to a WLAN network or a non-WLAN network to a WLAN network. Through the above method, after being connected to the current network (WLAN network or non-WLAN network), the terminal performs pre-authentication with the currently detected target network (non-WLAN network or WLAN network) that may become the handover target. The switching conditions (the setting of the switching conditions can be flexibly selected according to the current network and the target network and the specific needs of the application scenario). After the satisfaction, the target network can be directly switched, thereby greatly reducing the switching time. Avoid network disconnection caused by switching. The method proposed in this embodiment is mainly directed to the handover between the WLAN network and the non-WLAN network, but it is obvious that the method proposed in this embodiment can be applied to the network switching process of the terminal, because The terminal inevitably generates the switching time in the process of network switching, and the shorter the switching time, the smoother the switching process, and the less likely the network interruption occurs, so shorter switching is required in each network switching process of the terminal. Time, and the method proposed in this embodiment can further reduce the switching time for any network switching process, thereby achieving smoother network switching. In the foregoing embodiment, after the terminal is associated with the current network, multiple target networks that may become the handover target may be detected. In this special case, the corresponding selection policy needs to be matched to determine that the preset condition is met. Which target network to switch to, for example, switch to the first detected target network, or switch to the target network with the best signal strength, or switch the priority to the target network with the highest priority for each target network. The present invention is not limited in specific selection of the authentication method, and can be flexibly selected according to different needs. The preferred embodiment provides a preferred authentication mode. Preferably, the terminal performing pre-identification with the target network may include: the terminal invoking the authentication information in the SIM or the USIM to establish an identity authentication process of the terminal and the target network through the current network. The authentication information in the SIM or USIM is a very common authentication basis. The authentication information in the SIM or USIM is used to establish the identity authentication process between the terminal and the target network through the current network. This is very easy to implement and can ensure the successful completion of the pre-authentication. . Preferably, when the current network is a WLAN network and the target network is a non-WLAN network, the terminal invoking the authentication information in the SIM or the USIM to establish the identity authentication process of the terminal and the target network through the current network may include: (1) the terminal and the non-WLAN network pass The access point AP of the WLAN network to which the terminal is associated transmits the authentication information;

(2) The AP and the non-WLAN network transmit the key information through the wired network between the authentication server of the non-WLAN network and the RADIUS authentication server of the WLAN network, wherein the encryption mode of the key information follows the transmission protocol of the SIM authentication in the WLAN network. The preferred embodiment of the present invention provides a preferred pre-authentication process of the terminal and the target network when the target network is a non-WLAN network, that is, the terminal uses the AP of the WLAN network as the relay relay of the authentication information, The wired network between the authentication server of the non-WLAN network and the RADIUS authentication server of the WLAN network serves as a channel for transmitting key information, and finally completes identity authentication. Preferably, when the current network is a WLAN network and the target network is a non-WLAN network, the preset condition may include at least one of the following: a signal strength of the WLAN network is lower than a preset threshold, and a frame error rate of data transmission between the terminal and the WLAN network is performed. Above the preset threshold, the signal-to-noise ratio of the data transmission between the terminal and the WLAN network is lower than the preset threshold, and the WLAN network is detected. The preferred embodiment provides a preset condition that may be preferred when the current network is a WLAN network, and the target network is a non-WLAN network. In a specific implementation process, the available preset conditions include, but are not limited to, the preset conditions. Preferably, the current network is a non-WLAN network, and when the target network is a WLAN network, the terminal invoking the authentication information in the SIM or the USIM to establish the identity authentication process of the terminal and the target network through the current network may include:

(1) The terminal and the WLAN network transmit the authentication information through the authentication server of the non-WLAN network;

(2) The non-WLAN network and the WLAN network transmit the key information through the wired network between the authentication server of the non-WLAN network and the RADIUS authentication server of the WLAN network, and the RADIUS authentication server transmits the key information to the RADIUS authentication server. The associated AP, wherein the key information encryption mode follows the SIM authentication transmission protocol of the non-WLAN network and the WLAN network. Corresponding to the above preferred embodiment, the preferred embodiment provides a preferred pre-authentication process of the terminal and the target network when the target network is a WLAN network, that is, the terminal uses a non-WLAN network authentication server. As the relay relay of the authentication information, the wired network between the authentication server of the non-WLAN network and the RADIUS authentication server of the WLAN network serves as a channel for transmitting key information, and the RADIUS authentication server transmits the key information to the RADIUS authentication server. The AP associated with the RADIUS authentication server to finalize the authentication process. Preferably, when the current network is a non-WLAN network, and the target network is a WLAN network, the preset condition may include at least one of the following: detecting the WLAN network, and detecting that the signal strength of the WLAN network is greater than a preset threshold. The preferred embodiment provides a preset condition that the current network is a non-WLAN network, and the target network is a WLAN network. In the specific implementation, the available preset conditions include, but are not limited to, the preset conditions. Preferably, the foregoing authentication information may include: generating source code of the authentication key, framing details of the key frame, verification of the key frame, integrity of the key; the key information may include: an encryption mode and using the encryption mode Encrypted authentication information, wherein the encryption mode includes at least one of the following: non-encryption mode, RC4 encryption mode in WEP protocol, TKIP encryption mode in WPA protocol, AES encryption method in WPA2 protocol, WPI in WAPI protocol SMS4 encryption method. In principle, the authentication information should contain all the information required for the pre-authentication process, and the preferred embodiment gives several basic information required for the authentication process. The key information mainly includes the encryption mode and encryption using the encryption mode. After the authentication information, the selection of the specific encryption mode may be agreed in advance, including but not limited to the above encryption method, and the key information needs to be encrypted again when transmitting the key information, and the selection of the encryption mode needs to correspond to the corresponding transmission protocol. . The above preferred embodiments will be described in detail below with reference to examples. 2 is a schematic diagram showing the functional structure of a terminal according to an example of the present invention. As shown in FIG. 2, the terminal applied in this example can be roughly divided into three parts: a WLAN unit, a data transmission unit, and a pre-authentication unit.

The WLAN unit is mainly responsible for basic authentication and association operations of the WLAN, and is also used for information interaction with the data transmission unit to feedback the pre-authentication information. The data transmission unit is used for the normal data transmission process such as web browsing on the one hand, and the key information transmission process on the other hand, for example, the key information is transmitted to the WLAN unit, and the key information mainly includes: an encryption mode and use of the Encryption mode encrypted authentication information, where the encryption mode includes: non-encryption mode, RC4 encryption method required in WEP protocol, TKIP encryption method required in WPA protocol, AES encryption method required in WPA2 protocol, and required in WAPI protocol Encryption methods such as WPI-SMS4. The pre-authentication unit is mainly used for storing SIM authentication information of the WLAN network and the non-WLAN network, and analyzing and configuring the authentication information. The foregoing authentication information mainly includes: generating the source code of the authentication key, framing details of the key frame, Information such as the verification of the key frame, the integrity of the key, and so on. 3 is a schematic diagram of a process for a WLAN network to switch to a non-WLAN network according to an example of the present invention. As shown in FIG. 3, the method includes the following steps: Step S302: The terminal performs authentication and association with the current WLAN network, and stores authentication information of the current WLAN network. . The authentication and association process between the terminal and the WLAN network does not use the pre-identification method. The authentication process between the terminal and the WLAN network adopts a normal authentication process, which mainly includes: an authentication request, an authentication response, and an authentication key interaction. , key integrity check. Step S304, the terminal performs data transmission with the associated WLAN network. Step S306, the terminal invokes the stored SIM authentication information to establish an authentication process between the terminal and the current non-WLAN network in the process of data transmission with the associated WLAN network. The authentication interaction information transmission process between the terminal and the non-WLAN network is as shown in FIG. 4, that is, the AP that is associated with the current terminal is used as a relay to control SIM authentication information between the WLAN network and the non-WLAN network. The authentication information transmission process between the terminal and the non-WLAN network uses the AP associated with the current terminal as the relay, and the key information transmission process between the currently associated AP and the destination non-WLAN network uses the authentication server and the WLAN network of the non-WLAN network. The wired network transmission between the RADIUS authentication servers, the key information encryption mode follows the transmission protocol of the internal SIM authentication of the WLAN network, and the information such as the authentication request between the terminal and the non-WLAN network is completely performed by the currently associated AP. Step S308, the terminal switches to a non-WLAN network for data transmission. Whether the terminal disconnects the link with the currently associated WLAN network for non-WLAN network connection depends on the signal strength of the currently associated WLAN network, or depends on the frame error rate of data transmission between the terminal and the current WLAN network, or The signal-to-noise ratio of data transmission between the terminal and the current WLAN network, or depending on whether there is currently a non-WLAN network or the like. FIG. 5 is a schematic diagram of a process of switching a non-WLAN network to a WLAN network according to an example of the present invention. As shown in FIG. 5, the method includes the following steps: Step S502: The terminal performs authentication, association, and storage with a current non-WLAN network. Certification Information. The network registration authentication and association process of the terminal boot (U) SIM card does not use the pre-identification method. Step S504, the terminal performs data transmission with the associated non-WLAN network. Step S506, the terminal is stored in the process of data transmission with the associated non-WLAN network.

(U) The authentication information in the SIM card establishes an authentication process between the terminal and the current WLAN network through the currently associated non-WLAN network. The authentication interaction information transmission process between the terminal and the WLAN network is as shown in FIG. 6, that is, the SIM authentication server of the non-WLAN network that is associated with the current terminal is used as a relay to control the current associated non-WLAN network and the WLAN network. The certification process. The authentication information transmission process between the terminal and the WLAN network is performed by the authentication server of the current non-WLAN network, and the key information transmission process between the currently associated non-WLAN network and the destination WLAN network uses a non-WLAN network authentication server and a WLAN network. Wired network transfer between RADIUS authentication servers, The RADIUS authentication server then passes the authentication information to the AP associated with it. The key information encryption mode follows the SIM authentication transmission protocol of the non-WLAN network and the WLAN network, and the authentication request information between the terminal and the WLAN network is completely covered by the current non-WLAN network. The authentication server is responsible. Step S508, the terminal switches to the WLAN network for data transmission. When the terminal is disconnected from the current non-WLAN network and enters the WLAN network area, the terminal is directly associated with the authenticated WLAN network, and the data is transmitted. The terminal is disconnected from the currently associated non-WLAN network to perform the WLAN network association. Whether there is currently a WLAN network, the signal strength of the WLAN network, and the like. FIG. 7 is a structural block diagram of a network switching apparatus according to an embodiment of the present invention. As shown in FIG. 7, the network switching apparatus according to the embodiment of the present invention includes: a pre-authentication module 72, configured to perform pre-identification authentication with the detected target network after the terminal is associated with the current network; the direct switching module 74 is connected to The pre-authentication module 72 is configured to directly switch the terminal to the target network when the pre-condition is satisfied after the pre-authentication is successful. Preferably, the current network comprises one of the following: a WLAN network, a non-WLAN network; the target network includes one of the following: a WLAN network, a non-WLAN network. The device provided in this embodiment fully utilizes the idea of pre-authentication and applies it to the process of switching between a WLAN network and a non-WLAN network, that is, the terminal is switched from the WLAN network to the non-WLAN network or switched to the non-WLAN network. The process of WLAN network. Through the above device, after the terminal is associated with the current network (WLAN network or non-WLAN network), the terminal performs pre-authentication with the currently detected target network (non-WLAN network or WLAN network) that may become the handover target. Set the switching conditions (the setting of the switching conditions can be flexibly selected according to the current network and the target network and the specific needs of the application scenario). After the satisfaction, the target network can be directly switched, thereby greatly reducing the switching time. Avoid network disconnection caused by switching. The device proposed in this embodiment is mainly directed to the switching between the WLAN network and the non-WLAN network, but it is obvious that the device proposed in this embodiment is actually compatible with each network switching process of the terminal, because the terminal is in In the process of network switching, the switching time is inevitable, and the shorter the switching time, the smoother the switching process is, and the less likely the network interruption is, so in the network switching process of the terminal. A shorter switching time is required. The device proposed in this embodiment can reduce the switching time of any network switching process and achieve smoother network switching. From the above description, it can be seen that, by the technical solution provided by the present invention, when the terminal turns on the pre-authentication function, the AP that is currently associated with the WLAN network automatically invokes (U) the identity authentication information stored in the SIM card through the current The associated AP establishes the authentication process between the terminal and the non-WLAN network. When the data transmission error rate between the terminal and the currently associated AP is high, or the signal strength of the currently associated AP is low, the terminal automatically associates the authenticated non-WLAN. If the pre-authentication function is enabled when using a non-WLAN network, the authentication server currently associated with the non-WLAN network will automatically invoke (U) the identity authentication information stored in the SIM card to establish the terminal and the WLAN network through the RADIUS authentication server of the WLAN network. The authentication process automatically associates the authenticated WLAN network when the terminal finds that there is currently a WLAN network access point. The technical solution provided by the present invention implements fast switching between a WLAN network and a non-WLAN network, and can be applied to various types of network switching of the terminal, thereby improving the network switching efficiency of the terminal as a whole. Obviously, those skilled in the art should understand that the above modules or steps of the present invention can be implemented by a general-purpose computing device, which can be concentrated on a single computing device or distributed over a network composed of multiple computing devices. Alternatively, they may be implemented by program code executable by the computing device, such that they may be stored in the storage device by the computing device and, in some cases, may be different from the order herein. The steps shown or described are performed, or they are separately fabricated into individual integrated circuit modules, or a plurality of modules or steps are fabricated as a single integrated circuit module. Thus, the invention is not limited to any specific combination of hardware and software. The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes can be made to the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and scope of the present invention are intended to be included within the scope of the present invention.

Claims

A network switching method, comprising:

After the terminal is associated with the current network, the terminal performs pre-identification with the detected target network. After the pre-identification is successful, the terminal directly switches to the target network when the preset condition is met.

2. The method according to claim 1, wherein

The current network includes one of the following: a wireless local area network WLAN network, a non-WLAN network; the target network includes one of the following: a WLAN network, a non-WLAN network.

3. The method according to claim 2, wherein the pre-identification of the terminal with the target network comprises:

The terminal invokes the authentication information in the user identification module SIM or the global subscriber identity module USIM to establish an identity authentication process of the terminal and the target network by using the current network.

The method according to claim 3, wherein, when the current network is a WLAN network, and the target network is a non-WLAN network, the terminal invokes authentication information in the SIM or USIM through the current network establishment. The identity authentication process of the terminal and the target network includes:

The terminal and the non-WLAN network transmit the authentication information by using an access point AP of the WLAN network that the terminal has associated with;

Transmitting key information between the AP and the non-WLAN network through a wired network between an authentication server of the non-WLAN network and a remote authentication user of the WLAN network dialed into a serving RADIUS authentication server, where the key The encryption mode of the information follows the transmission protocol of the SIM authentication within the WLAN network.

5. The method according to claim 4, wherein the preset condition comprises at least one of: a signal strength of the WLAN network is lower than a preset threshold, and data transmission between the terminal and the WLAN network is performed. The frame error rate is higher than the preset threshold, and the signal to noise ratio of the data transmission between the terminal and the WLAN network is lower than a preset threshold, and a non-WLAN network is detected. The method according to claim 3, wherein, when the current network is a non-WLAN network, and the target network is a WLAN network, the terminal calls the authentication information in the SIM or the USIM to establish the terminal through the current network. The identity authentication process with the target network includes:

Transmitting, by the terminal, the authentication information to the WLAN network by using an authentication server of the non-WLAN network;

The non-WLAN network and the WLAN network transmit key information through a wired network between the authentication server of the non-WLAN network and the RADIUS authentication server of the WLAN network, and the RADIUS authentication server transmits the key information again An AP associated with the RADIUS authentication server, wherein the key information encryption mode follows a SIM authentication transmission protocol of the non-WLAN network and the WLAN network. The method according to claim 6, wherein the preset condition comprises at least one of the following: detecting a WLAN network, and detecting a signal strength of the WLAN network is greater than a preset threshold. The method according to any one of claims 4 to 7, wherein

The authentication information includes: a source code for generating an authentication key, a framing detail of a key frame, a check of a key frame, and a integrity of the key;

The key information includes: an encryption mode and authentication information encrypted by using the encryption mode, wherein the encryption mode includes at least one of the following: an unencrypted mode, an RC4 encryption method in a valid equivalent secure WEP protocol, and a Wi- Fi protection access to the temporary key integrity protocol TKIP encryption method in the WPA protocol, the advanced encryption standard AES encryption method in the WPA2 protocol, the wireless local area network authentication and the privacy infrastructure WAPI protocol, the wireless local area network security infrastructure WPI-SMS4 encryption method . A network switching device includes:

a pre-authentication module, configured to perform pre-identification with the detected target network after the terminal is associated with the current network;

The direct switching module is configured to directly switch the terminal to the target network when the preset condition is satisfied after the pre-authentication is successful. The device according to claim 9, wherein