DIRECT LINK ADDRESSING METHOD AND APPARATUS.

Abstract

This application provides a direct link addressing method and apparatus, enabling direct communication between two non-AP MLDs, or between an STA and a non-AP MLD, thereby improving data transmission efficiency. This application can be applied to a Wi-Fi system. The method applies to a first device, which includes one or more STAs. The first device connects to a third device, which includes multiple access points (APs). A second device connects to the third device, which includes multiple STAs. When the first device includes an STA, the protected data is constructed using an address from the first device, an address from the second device, and an address from a first AP connected to the first device.When the first device includes multiple STAs, the protected data is constructed using an address from the first device, an address from the second device, and an address from the third device. Therefore, the first device can transmit a first unit of data through a direct link between the first and second devices, thus increasing the data transmission rate.

Description

DIRECT LINK ADDRESSING METHOD AND DEVICE ινΐΛ / a / zuzó / u i ut The present application claims the priority of Chinese Patent Application no. 202110278095.3, filed with the National Intellectual Property Administration of China on March 15, 2021 and titled DIRECT LINK ADDRESSING METHOD AND APPARATUS, which is incorporated herein by reference in its entirety. FIELD OF THE INVENTION This application relates to the communication field and, in particular, to a direct link addressing method and apparatus. BACKGROUND OF THE INVENTION With the development of wireless communication technologies, the increase in wireless communication devices supports multi-link communication, to improve the communication efficiency of communication devices. A communication device that supports multilink communication can be called a multi-link device (MLD). The multilink device includes an MLD access point (AP) and a MLD non-access point (non-AP). The AP MLD includes a plurality of APs, and the non-AP MLD includes a plurality of STA stations. When a communication system includes at least one MLD AP and a plurality of non-AP MLDs, a non-AP MLD can communicate with an MLD AP through a plurality of links, and two non-AP MLDs can communicate with each other through the use of an MLD AP. The communication system may further include a station device (STA). The STA device includes a STA, and the STA device can communicate with a non-AP MLD by using an MLD AP. However, the communication between the two non-AP MLDs or between the STA device and the non-AP MLD still needs to be forwarded when using the AP MLD, which increases a transmission delay. To know how to establish a direct link between a first non-AP MLD and a second non-AP MLD or between a STA device and a non-AP MLD for communication, there is no corresponding solution available in the industry. BRIEF DESCRIPTION OF THE INVENTION Embodiments of this application provide a direct link addressing method and apparatus, so that direct communication can be realized between a non-AP MLD and a non-AP MLD, or between a STA device and a non-AP MLD, thereby improving the efficiency of data transmission. To achieve the above objective, this application uses the following technical solutions. According to a first aspect, a direct link addressing method is provided, applied to a first device. The first device includes one or more STA stations. The first device connects to a third device, and the third device includes a plurality of access point APs. A second device connects to the third device, and the second device includes a plurality of STAs. The direct link addressing method includes: determining protected data and sending a first unit of data. The protected data includes a first address, a second address and a third address. When the first device includes a STA, the first address is an address of the second device, the second address is an address of the first device, the third address is an address of a first AP of the third device, and the first device connects to the first AP of the third device. When the first device includes a plurality of STAs, the first address is an address of the second device, the second address is an address of the first device, and the third address is an address of the third device. The first data unit includes a first header, the first header is determined based on the protected data, and the first data unit is transmitted over a direct link between the first device and the second device. According to the direct link addressing method described in the first aspect, when the first device includes a STA, the protected data is constructed by using the address of the first device, the address of the second device, and the address of the first AP connected to the first device. When the first device includes a plurality of STAs, the protected data is constructed by using the address of the first device, the address of the second device, and the address of the third device. Therefore, the first device can transmit the first unit of data through the direct link between the first device and the second device, thereby increasing a data transmission rate. Furthermore, when the first device includes a plurality of STAs, the protected data is constructed by using the addresses of the devices, and a change of the direct link does not affect the protected data. Therefore, when data is transmitted over a plurality of direct links, encryption does not need to be performed again, which further increases the data transmission speed. Optionally, the protected data may be additional authentication data (AAD), and the first data unit may be a management protocol data unit (MPDU). In one possible design, the first header may include a fourth address, a fifth address, and a sixth address. When the first device includes a STA, the fourth address is an address of the second device, the fifth address is an address of the first device, and the sixth address is an address of the first AP of the third device. In this way, a legacy STA and the second device can communicate via iviA / a / zuzo / u i ut a direct link, thus increasing a data transmission rate. Optionally, the first header may be an MPDU header. In one possible design, the first header may include a fourth address, a fifth address, and a sixth address. When the first device includes a plurality of STAs, the fourth address is an address of a STA that corresponds to a first direct link and is located in the plurality of STAs of the second device, the fifth address is an address of a STA that corresponds to the first direct link and which is located in the plurality of STAs of the first device, the sixth address is an address of an AP that corresponds to the first direct link and which is located in the plurality of APs of the third device, and the first direct link It is a direct link between the first device and the second device. In this way, a non-AP MLD and a non-AP MLD can communicate over a direct link, thereby increasing a data transmission rate. In one possible design form, the first data unit may include a Tunneled Direct-Link Setup (TDLS) frame. The TDLS frame may include a first element, and the first element may indicate an identifier of a target link or an address of an AP that corresponds to the target link and is located in the plurality of APs of the third device. The target link is a second direct link to which the TDLS frame is applied, and the second direct link is a direct link between the first device and the second device. In this way, for a link-level (link-level) TDLS frame, a specific direct link to which the TDLS frame applies can be indicated. Optionally, the TDLS frame may be a TDLS Channel Switch Request frame or a TDLS Channel Switch Response frame. The TDLS channel switching request frame is used to request the target link to switch from one current channel to another channel, and the TDLS channel switching response frame indicates whether the target link accepts switching from the current channel to the other channel. In this way, the first device and the second device can switch the target link from the current channel to the other channel for communication. In a multilink TDLS scenario, the TDLS channel switching request / response frame can be transmitted over any direct link. Optionally, the first element can be a Link Identifier element or a newly defined element. In a possible design, when the first device includes a STA, and the TDLS frame is a TDLS discovery request frame, the first element may indicate an identifier of a transmission link or an address of an AP that corresponds to the transmission link and which is located in the plurality of APs of the third device, where the transmission link is a link for sending the TDLS discovery request frame. In this way, the legacy STA and the second device can communicate over the direct link, thus increasing the data transmission rate. In a possible design, when the first device includes a STA, and the TDLS frame is a TDLS discovery response frame, the first element indicates an identifier of a transmission link or an address of an AP that corresponds to the transmission link and which is located in the plurality of APs of the third device, where the transmission link is a link for sending the TDLS discovery request frame. In other words, the configured content of the first element corresponding to the TDLS frame that is a TDLS discovery response frame is the same as the configured content of the first element corresponding to the TDLS frame that is a TDLS discovery request frame. In this way, the legacy STA and the second device can communicate over the direct link, thereby increasing the data transmission rate. In one possible design, when the first device includes a STA, and the TDLS frame is a TDLS configuration request frame, the first element indicates an identifier of a link between the first device and the third device, or an address of an AP corresponding to the first device and located in the plurality of APs of the third device, and the transmission link is a link for sending the TDLS discovery request frame. In this way, the legacy STA and the second device can communicate over the direct link, thereby increasing the data transmission rate. In a possible design, when the first device includes a STA, and the TDLS frame is a TDLS configuration response frame, a TDLS configuration confirmation frame, a TDLS abort frame, a TDLS channel switching request frame, a TDLS channel switching response frame, a TDLS peer power saving management request frame, a TDLS peer power saving management response frame, a TDLS peer traffic indication frame, or a of TDLS peer traffic response, for a specific implementation of the first element, see the previous implementation of the first element when the first device includes a STA and the TDLS frame is a TDLS configuration request frame. No details are described again herein. In this way, the non-AP MLD and the non-AP MLD can communicate through the direct link, thereby increasing the data transmission rate. In a possible design, when the first device includes a plurality of STAs, and the TDLS frame is a TDLS discovery request frame, the first element indicates an identifier of a reference link or an address of an AP that corresponds to the reference link. reference and which is located in the plurality of APs of the third device. Optionally, the reference link may be a link indicated by a BSSID field in the link identifier element. In this way, the non-AP MLD and the non-AP MLD can communicate to iviA / a / zuzo / u i uz fó through the direct link, thereby increasing the data transmission speed. In a possible design, when the first device includes a plurality of STAs, and the TDLS frame is a TDLS discovery response frame, the first element indicates an identifier of a common link for transmitting the TDLS discovery response frame, or a address of an AP that corresponds to the common link for transmitting the TDLS discovery response frame and that is located in the plurality of APs of the third device. The common link is a common link of a link between the first device and the third device and a link between the second device and the third device, and an AP of the third device associated with a STA of the first device corresponding to the common link is the same than an AP of the third device associated with a STA of the second device corresponding to the common link. In this way, the non-AP MLD and the non-AP MLD can communicate through the direct link, thereby increasing the data transmission rate. In a possible design, when the first device includes a plurality of STAs, and the TDLS frame is a TDLS configuration request frame, a TDLS configuration response frame, or a TDLS configuration confirmation frame, the first element indicates an identifier of a reference link, or an address of an AP that corresponds to the reference link and that is located in the plurality of APs of the third device. In this way, a receiving end can know that a specific link is a corresponding reference link. In one possible design, when the first device includes a plurality of STAs, and the TDLS frame is a TDLS override frame, the first element indicates an address of the third device. In this way, a receiving end can know that the frame is sent by which device associated with which MLD AP. In a possible design, when the first device includes a plurality of STAs, and the TDLS frame is a TDLS peer traffic indication frame or a TDLS peer traffic response frame, the first element indicates an address of the third device. In this way, a receiving end can know that the frame is sent by which device associated with which MLD AP. In one possible design manner, the first data unit may include the tunneled direct link configuration TDLS frame, and the TDLS frame may include a wake-up scheduling element and a second element. An offset field in the activation scheduling element is an offset with respect to a first timing synchronization function threshold of a third direct link, the second element may indicate an identifier of the third direct link or an address of an AP that corresponds to the third direct link and which are located in the plurality of APs of the third device, and the third direct link is a direct link between the first device and the second iviA / a / zuzo / u i ut device. This way, a time can be precisely learned when data is periodically woken up and received / sent, to reduce power consumption. Optionally, the TDLS frame may be a TDLS peer power saving management request frame or a TDLS peer power saving management response frame. In this way, in the multi-link TDLS scenario, the PSM request / response frame of TDLS peers can be transmitted over any direct link, and the receiving end can correctly parse the trigger scheduling element. In one possible design manner, the first data unit may include a third element, and the third element may indicate configuring at least a fourth direct link on a first link. The first link is a common link of the link between the first device and the third device and the link between the second device and the third device, and the first link may include the at least a fourth direct link. In this way, the first device and the second device can establish a direct link on the common link, to increase a data transmission rate. In other words, the first link may be a common link between the first device and the third device and between the second device and the third device, and an AP of the third device associated with a STA of the first device corresponding to the first link is the same than an AP of the third device associated with a STA of the second device corresponding to the first link. In one possible design, the third element may include a number of direct link fields and a direct link identifier field, the number of direct link fields may indicate a number of requested fourth direct links to be configured, and the direct link identifier field may include an address of at least one AP that separately corresponds to the at least one fourth direct link and is located in the plurality of APs of the third device or an identifier of the at least one fourth direct link. In this way, the number of fourth direct links to be established is indicated, so that the fourth direct link can be established on some or all of the links of the first link, thus improving the flexibility of establishing a direct link. The direct link identifier field can be used to indicate links on which direct links are configured. In one possible design, the forward link identifier field may further include an address of a first STA of the first device and an address of a second STA of the second device. In other words, the direct link identifier field may include addresses of affiliated STAs at two ends of the direct link. In one possible design way, a seventh address is linked to a pair key iviA / a / zuzo / u i ut TDLS (TDLS peer key, TPK), and the seventh address is an address of an AP that corresponds to the direct link between the first device and the second device and is located in the plurality of APs of the third device or addresses of all APs of the third device, and the address of the third device. In this way, the security of communication between the first device and the second device through the direct link can be improved. According to a second aspect, a direct link addressing method is provided, applied to a second device. The second device includes a plurality of STA stations. The second device connects to a third device, and the third device includes a plurality of access point APs. A first device connects to the third device, and the first device includes one or more STAs. The direct link addressing method includes: receiving a first data unit and parsing the first data unit to obtain a first header. The first data unit is transmitted over a direct link between the first device and the second device, and the first header may include a fourth address, a fifth address, and a sixth address. When the first device includes a STA, the fourth address is an address of the second device, the fifth address is an address of the first device, and the sixth address is an address of the first AP of the third device. When the first device includes a plurality of STAs, the fourth address is an address of a STA that corresponds to a first direct link and is located in the plurality of STAs of the second device, the fifth address is an address of a STA that corresponds to the first direct link and which is located in the plurality of STAs of the first device, the sixth address is an address of an AP that corresponds to the first direct link and which is located in the plurality of APs of the third device, and the first direct link It is a direct link between the first device and the second device. In a possible design manner, the direct link addressing method provided in the second aspect may further include: obtaining protected data based on the first header. The protected data includes a first address, a second address and a third address. When the first device includes a STA, the first address is an address of the second device, the second address is an address of the first device, the third address is an address of the first AP of the third device, and the first device connects to the first AP of the third device. When the first device includes a plurality of STAs, the first address is an address of the second device, the second address is an address of the first device, and the third address is an address of the third device. In a possible design manner, the direct link addressing method provided in the second aspect may further include: parsing the first data unit iviA / a / zuzo / u i ut fó to obtain a Tunneled Direct link configuration frame. -Link Setup, TDLS), where the TDLS frame may include a first element, the first element may indicate an identifier of a target link or an address of an AP that corresponds to the target link and that is located in the plurality of APs of the third device, the target link is a second direct link to which the TDLS frame is applied, and the second direct link is a direct link between the first device and the second device. Optionally, the TDLS frame may be a TDLS Channel Switch Request frame or a TDLS Channel Switch Response frame. The TDLS channel switching request is used to request the target link to switch from one current channel to another channel, and the TDLS channel switching response frame indicates whether the target link accepts switching from the current channel to the other channel. In a possible design, when the first device includes a STA, and the TDLS frame is a TDLS discovery request frame, the first element may indicate an identifier of a transmission link or an address of an AP that corresponds to the transmission link and which is located in the plurality of APs of the third device, where the transmission link is a link for sending the TDLS discovery request frame. In a possible design, when the first device includes a STA, and the TDLS frame is a TDLS discovery response frame, the first element indicates an identifier of a transmission link or an address of an AP that corresponds to the transmission link and which is located in the plurality of APs of the third device, where the transmission link is a link for sending the TDLS discovery request frame. In other words, the configured content of the first element corresponding to the TDLS frame that is a TDLS discovery response frame is the same as the configured content of the first element corresponding to the TDLS frame that is a TDLS discovery request frame. In one possible design, when the first device includes a STA, and the TDLS frame is a TDLS configuration request frame, the first element indicates an identifier of a link between the first device and the third device, or an address of an AP corresponding to the first device and located in the plurality of APs of the third device, and the transmission link is a link for sending the TDLS discovery request frame. In a possible design, when the first device includes a STA, and the TDLS frame is a TDLS configuration response frame, a TDLS configuration confirmation frame, a TDLS abort frame, a TDLS channel switching request frame, a TDLS channel switching response frame, a TDLS peer power saving iviA / a / zuzo / u i ut management request frame, a TDLS peer power saving management response frame, an indication frame of TDLS peer traffic or a TDLS peer traffic response frame, for a specific implementation of the first element, see the previous implementation of the first element when the first device includes a STA and the TDLS frame is a TDLS configuration request frame. No details are described again herein. In a possible design, when the first device includes a plurality of STAs, and the TDLS frame is a TDLS discovery request frame, the first element indicates an identifier of a reference link or an address of an AP that corresponds to the reference link. reference and which is located in the plurality of APs of the third device. Optionally, the reference link may be a link indicated by a BSSID field in a link identifier element. In a possible design, when the first device includes a plurality of STAs, and the TDLS frame is a TDLS discovery response frame, the first element indicates an identifier of a common link for transmitting the TDLS discovery response frame, or a address of an AP that corresponds to the common link for transmitting the TDLS discovery response frame and that is located in the plurality of APs of the third device. The common link is a common link of a link between the first device and the third device and a link between the second device and the third device, and an AP of the third device associated with a STA of the first device corresponding to the common link is the same than an AP of the third device associated with a STA of the second device corresponding to the common link. In a possible design, when the first device includes a plurality of STAs, and the TDLS frame is a TDLS configuration request frame, a TDLS configuration response frame, or a TDLS configuration confirmation frame, the first element indicates an identifier of a reference link, or an address of an AP that corresponds to the reference link and that is located in the plurality of APs of the third device. In one possible design, when the first device includes a plurality of STAs, and the TDLS frame is a TDLS override frame, the first element indicates an address of the third device. In a possible design, when the first device includes a plurality of STAs, and the TDLS frame is a TDLS peer traffic indication frame or a TDLS peer traffic response frame, the first element indicates an address of the third device. In a possible design manner, the direct link addressing method provided in the second aspect may further include: parsing the first data unit to obtain the TDLS frame, where the TDLS frame may include a programming element iviA / a / zuzo / u i ut activation and a second element. An offset field in the activation scheduling element is an offset with respect to a first timing synchronization function threshold of a third direct link, the second element may indicate an identifier of the third direct link or an address of an AP that corresponds to the third direct link and which are located in the plurality of APs of the third device, and the third direct link is a direct link between the first device and the second device. Optionally, the TDLS frame may be a TDLS peer power saving management request frame or a TDLS peer power saving management response frame. In a possible design manner, the direct link addressing method provided in the second aspect may further include: parsing the first data unit to obtain a third element, where the third element may indicate configuring at least a fourth direct link in a first link. The first link is a common link of the link between the first device and the third device and the link between the second device and the third device, and the first link may include the at least a fourth direct link. In one possible design, the third element may include a number of direct link fields and a direct link identifier field, the number of direct link fields may indicate a number of requested fourth direct links to be configured, and The direct link identifier field may include an address of at least one AP that separately corresponds to the at least one fourth direct link and is located in the plurality of APs of the third device or an identifier of the at least one fourth direct link . In one possible design, the forward link identifier field may further include an address of a first STA of the first device and an address of a second STA of the second device. In one possible design, a seventh address is linked to a TDLS pair key, and the seventh address may include an address of an AP that corresponds to the direct link between the first device and the second device and that is located in the plurality of AP of the third device or addresses of all APs of the third device, and the address of the third device. Furthermore, for a technical effect of the direct link addressing method according to the second aspect, reference is made to the technical effect of the direct link addressing method according to the first aspect. No details are described again herein. According to a third aspect, a direct link addressing method is provided, applied to a second device. The second device includes a plurality iviA / a / zuzo / u i ut of STA stations. The second device connects to a third device, and the third device includes a plurality of access point APs. A first device connects to the third device, and the first device includes one or more STAs. The direct link addressing method includes: determining protected data and sending a first unit of data. The protected data includes a first address, a second address and a third address. When the first device includes a STA, the first address is an address of the second device, the second address is an address of the second device, the third address is an address of a first AP of the third device, and the first device connects to the first AP of the third device. When the first device includes a plurality of STAs, the first address is an address of the first device, the second address is an address of the second device, and the third address is an address of the third device. The first data unit includes a first header, the first header is determined based on the protected data, and the first data unit is transmitted over a direct link between the first device and the second device. In one possible design, the first header may include a fourth address, a fifth address, and a sixth address. When the first device includes a STA, the fourth address is an address of the first device, the fifth address is an address of the second device, and the sixth address is an address of the first AP of the third device. In this way, protocol compatibility is maintained. When the second device is used as a TDLS initiator, a legacy STA can successfully parse the first data unit, so that the legacy STA can communicate with a non-AP MLD over a direct link, thereby increasing a transmission rate of data. In one possible design manner, the first header includes a fourth address, a fifth address, and a sixth address. When the first device includes a plurality of STAs, the fourth address is an address of a STA that corresponds to a first direct link and is located in the plurality of STAs of the first device, the fifth address is an address of a STA that corresponds to the first direct link and which is located in the plurality of STAs of the second device, the sixth address is an address of an AP that corresponds to the first direct link and which is located in the plurality of APs of the third device, and the first direct link It is a direct link between the first device and the second device. In one possible design, the first data unit may include a tunneled direct link configuration TDLS frame. The TDLS frame may include a first element, and the first element may indicate an identifier of a target link or an address of an AP that corresponds to the target link and is located in the plurality of APs of the third device. The target link is a second direct link to which the TDLS frame is applied, and the second direct link is a direct link between the first device and the second device. In one possible design manner, the first data unit may include the tunneled direct link configuration TDLS frame, and the TDLS frame may include a wake-up scheduling element and a second element. An offset field in the activation scheduling element is an offset with respect to a first timing synchronization function threshold of a third direct link, the second element may indicate an identifier of the third direct link or an address of an AP that corresponds to the third direct link and which are located in the plurality of APs of the third device, and the third direct link is a direct link between the first device and the second device. In a possible design, when the first device includes a STA, and the TDLS frame is a TDLS discovery request frame, the first element indicates an identifier of a reference link or an address of an AP that corresponds to the reference link and which is located in the plurality of APs of the third device. The reference link may be a link indicated by a BSSID field in a link identifier element. In this way, protocol compatibility is maintained. In a possible design, when the first device includes a STA, and the TDLS frame is a TDLS discovery response frame, the first element indicates an identifier of a transmission link or an address of an AP that corresponds to the transmission link and which is located in the plurality of APs of the third device, where the transmission link is a link for sending the TDLS discovery request frame. In other words, the configured content of the first element corresponding to the TDLS frame that is a TDLS discovery response frame is the same as the configured content of the first element corresponding to the TDLS frame that is a TDLS discovery request frame. In this way, protocol compatibility is maintained. In one possible design, when the first device includes a STA, and the TDLS frame is a TDLS configuration request frame, the first element indicates an identifier of a link between the first device and the third device, or an address of an AP corresponding to the first device and located in the plurality of APs of the third device, and the transmission link is a link for sending the TDLS discovery request frame. In this way, protocol compatibility is maintained. In a possible design, when the first device includes a STA, and the TDLS frame is a TDLS configuration response frame, a TDLS configuration confirmation frame, a TDLS abort frame, a TDLS channel switching request frame, a TDLS channel switching response frame, a TDLS peer power saving management request frame, a TDLS peer power saving management response frame, a TDLS peer traffic indication or a TDLS peer traffic response frame, for a specific implementation of the first element, see the previous implementation of the first element when the first device includes a STA and the TDLS frame is a TDLS configuration request frame . No details are described again herein. In this way, protocol compatibility is maintained. In a possible design, when the first device includes a plurality of STAs, and the TDLS frame is a TDLS discovery request frame, the first element indicates an identifier of a reference link or an address of an AP that corresponds to the reference link. reference and which is located in the plurality of APs of the third device. Optionally, the reference link may be a link indicated by a BSSID field in a link identifier element. In a possible design, when the first device includes a plurality of STAs, and the TDLS frame is a TDLS discovery response frame, the first element indicates an identifier of a common link for transmitting the TDLS discovery response frame, or a address of an AP that corresponds to the common link for transmitting the TDLS discovery response frame and that is located in the plurality of APs of the third device. The common link is a common link of a link between the first device and the third device and a link between the second device and the third device, and an AP of the third device associated with a STA of the first device corresponding to the common link is the same than an AP of the third device associated with a STA of the second device corresponding to the common link. In a possible design, when the first device includes a plurality of STAs, and the TDLS frame is a TDLS configuration request frame, a TDLS configuration response frame, or a TDLS configuration confirmation frame, the first element indicates an identifier of a reference link, or an address of an AP that corresponds to the reference link and that is located in the plurality of APs of the third device. In one possible design, when the first device includes a plurality of STAs, and the TDLS frame is a TDLS override frame, the first element indicates an address of the third device. In a possible design, when the first device includes a plurality of STAs, and the TDLS frame is a TDLS peer traffic indication frame or a TDLS peer traffic response frame, the first element indicates an address of the third device. In one possible design manner, the first data unit may include a third element, and the third element may indicate configuring at least a fourth direct link on a first link. The first link is a common link of the link between the first device and the third device and the link between the second device and the third device, and the first link may include the at least a fourth direct link. In one possible design, the third element may include a number of direct link fields and a direct link identifier field, the number of direct link fields may indicate a number of requested fourth direct links to be configured, and The direct link identifier field may include an address of at least one AP that separately corresponds to the at least one fourth direct link and is located in the plurality of APs of the third device or an identifier of the at least one fourth direct link . In one possible design, the forward link identifier field may further include an address of a first STA of the first device and an address of a second STA of the second device. In one possible design, a seventh address is linked to a TDLS TPK pair key, and the seventh address may include an address of an AP that corresponds to the direct link between the first device and the second device and that is located in the plurality of APs of the third device or addresses of all APs of the third device, and the address of the third device. Furthermore, for a technical effect of the direct link addressing method according to the third aspect, reference is made to the technical effect of the direct link addressing method according to the first aspect. No details are described again herein. According to a fourth aspect, a direct link addressing method is provided, applied to a first device. The first device includes one or more STA stations. The first device connects to a third device, and the third device includes a plurality of access point APs. A second device connects to the third device, and the second device includes a plurality of STAs. The direct link addressing method includes: receiving a first data unit and parsing the first data unit to obtain a first header. The first unit of data is transmitted over a direct link between the first device and the second device. The first header may include a fourth address, a fifth address, and a sixth address. When the first device includes a STA, the fourth address is an address of the first device, the fifth address is an address of the second device, and the sixth address is an address of a first AP of the third device. When the first device includes a plurality of STAs, the fourth address is an address of a STA that corresponds to a first direct link and is located in the plurality of STAs of the first device, the fifth address is an address of a STA that corresponds to the first direct link and which is found in the plurality of STAs of the second device, the sixth address is an address of an AP that corresponds to the first direct link and which is found in the plurality of APs of the third device, and the first direct link is a direct link between the first device and the second device. In a possible design manner, the direct link addressing method provided in the fourth aspect may further include: obtaining protected data based on the first header. The protected data includes a first address, a second address and a third address. When the first device includes a STA, the first address is an address of the first device, the second address is an address of the second device, the third address is an address of the first AP of the third device, the first device connects to the first AP of the third device and the first device includes a STA. When the first device includes a plurality of STAs, the first address is an address of the first device, the second address is an address of the second device, and the third address is an address of the third device. In a possible design manner, the direct link addressing method provided in the fourth aspect may further include: parsing the first data unit to obtain a tunneled direct link configuration TDLS frame, where the TDLS frame may include a first element , the first element may indicate an identifier of a target link or an address of an AP that corresponds to the target link and is located in the plurality of APs of the third device, the target link is a second direct link to which the frame is applied TDLS, and the second direct link is a direct link between the first device and the second device. In a possible design, when the first device includes a STA, and the TDLS frame is a TDLS discovery request frame, the first element indicates an identifier of a reference link or an address of an AP that corresponds to the reference link and which is located in the plurality of APs of the third device. The reference link may be a link indicated by a BSSID field in a link identifier element. In a possible design, when the first device includes a STA, and the TDLS frame is a TDLS discovery response frame, the first element indicates an identifier of a transmission link or an address of an AP that corresponds to the transmission link and which is located in the plurality of APs of the third device, where the transmission link is a link for sending the TDLS discovery request frame. In other words, the configured content of the first element corresponding to the TDLS frame that is a TDLS discovery response frame is the same as the configured content of the first element corresponding to the TDLS frame that is a TDLS discovery request frame. ινΐΛ / a / zuzó / u i ut In one possible design, when the first device includes a STA, and the TDLS frame is a TDLS configuration request frame, the first element indicates an identifier of a link between the first device and the third device, or an address of an AP corresponding to the first device and located in the plurality of APs of the third device, and the transmission link is a link for sending the TDLS discovery request frame. In a possible design, when the first device includes a STA, and the TDLS frame is a TDLS configuration response frame, a TDLS configuration confirmation frame, a TDLS abort frame, a TDLS channel switching request frame, a TDLS channel switching response frame, a TDLS peer power saving management request frame, a TDLS peer power saving management response frame, a TDLS peer traffic indication frame, or a of TDLS peer traffic response, for a specific implementation of the first element, see the previous implementation of the first element when the first device includes a STA and the TDLS frame is a TDLS configuration request frame. No details are described again herein. In a possible design, when the first device includes a plurality of STAs, and the TDLS frame is a TDLS discovery request frame, the first element indicates an identifier of a reference link or an address of an AP that corresponds to the reference link. reference and which is located in the plurality of APs of the third device. Optionally, the reference link may be a link indicated by a BSSID field in the link identifier element. In a possible design, when the first device includes a plurality of STAs, and the TDLS frame is a TDLS discovery response frame, the first element indicates an identifier of a common link for transmitting the TDLS discovery response frame, or a address of an AP that corresponds to the common link for transmitting the TDLS discovery response frame and that is located in the plurality of APs of the third device. The common link is a common link of a link between the first device and the third device and a link between the second device and the third device, and an AP of the third device associated with a STA of the first device corresponding to the common link is the same than an AP of the third device associated with a STA of the second device corresponding to the common link. In a possible design, when the first device includes a plurality of STAs, and the TDLS frame is a TDLS configuration request frame, a TDLS configuration response frame, or a TDLS configuration confirmation frame, the first element indicates an identifier of a reference link, or an address of an AP that corresponds to the reference link and that is located in the plurality of APs of the third device. In one possible design, when the first device includes a plurality of STAs, and the TDLS frame is a TDLS override frame, the first element indicates an address of the third device. In a possible design, when the first device includes a plurality of STAs, and the TDLS frame is a TDLS peer traffic indication frame or a TDLS peer traffic response frame, the first element indicates an address of the third device. In a possible design manner, the direct link addressing method provided in the fourth aspect may further include: parsing the first data unit to obtain the TDLS frame, where the TDLS frame may include a trigger scheduling element and a second element. An offset field in the activation scheduling element is an offset with respect to a first timing synchronization function threshold of a third direct link, the second element may indicate an identifier of the third direct link or an address of an AP that corresponds to the third direct link and which are located in the plurality of APs of the third device, and the third direct link is a direct link between the first device and the second device. Optionally, the TDLS frame may be a TDLS peer power saving management request frame or a TDLS peer power saving management response frame. In a possible design manner, the direct link addressing method provided in the fourth aspect may further include: parsing the first data unit to obtain a third element, where the third element may indicate configuring at least a fourth direct link in a first link. The first link is a common link of the link between the first device and the third device and the link between the second device and the third device, and the first link may include the at least a fourth direct link. In one possible design, the third element may include a number of direct link fields and a direct link identifier field, the number of direct link fields may indicate a number of requested fourth direct links to be configured, and The direct link identifier field may include an address of at least one AP that separately corresponds to the at least one fourth direct link and is located in the plurality of APs of the third device or an identifier of the at least one fourth direct link . In a possible design manner, the forward link identifier field may further include an address of a first STA of the first device and an address of a second STA of the second device. In one possible design way, a seventh address is linked to a pair key iviA / a / zuzo / u i ut TDLS TPK, and the seventh address may include an address of an AP that corresponds to the direct link between the first device and the second device and that is located in the plurality of APs of the third device or addresses of all APs of the third device, and the address of the third device. Furthermore, for a technical effect of the direct link addressing method according to the fourth aspect, reference is made to the technical effect of the direct link addressing method according to the first aspect. No details are described again herein. According to a fifth aspect, a direct link addressing method is provided, applied to a first device. The first device includes one or more STA stations. The first device connects to a third device, and the third device includes a plurality of access point APs. A second device connects to the third device, and the second device includes a plurality of STAs. The direct link addressing method includes: determining a first data unit and sending the first data unit. The first data unit includes a first header, and the first header includes a fourth address, a fifth address, and a sixth address. When the first device includes a STA, the fourth address is an address of the second device, the fifth address is an address of the first device, the sixth address is an address of a first AP of the third device, and the first device connects to the first AP of the third device. When the first device includes a plurality of STAs, the fourth address is an address of the second device, the fifth address is an address of the first device, and the sixth address is an address of an AP that corresponds to a sixth direct link and is located in the plurality of APs of the third device, where the sixth direct link is a link for transmitting the first unit of data between the first device and the second device. The first unit of data is transmitted over a direct link between the first device and the second device. In one possible design manner, the first data unit further includes a frame body, and the frame body may be a TDLS frame or data. Optionally, the TDLS frame may be a TDLS discovery response frame. According to the direct link addressing method provided in the fifth aspect, when the first device includes a STA, the first header is constructed by using the address of the first device, the address of the second device and the address of the first AP connected to the first device. When the first device includes a plurality of STAs, the first header when constructed by using the address of the first device, the address of the second device and the address of the AP corresponding to the sixth direct link iviA / a / zuzo / u i ut fó y which is located in the plurality of APs of the third device, where the sixth direct link is a link for transmitting the TDLS frame between the first device and the second device. Therefore, the first device can transmit the first unit of data through the direct link between the first device and the second device, without forwarding by the third device, thereby increasing a data transmission rate. Furthermore, a way of configuring the sixth address may be the same in both a case where the first device includes a STA and a case where the first device includes a plurality of STAs, to avoid frequent modification of the configured content. of the sixth address, thus further reducing a transmission delay. Optionally, the TDLS frame may be a TDLS discovery response frame. The TDLS discovery response frame is encapsulated in a common management frame and does not need to be encrypted. Therefore, the corresponding AAD construct may not be determined. According to a sixth aspect, a direct link addressing method is provided, applied to a second device. The second device includes a plurality of STA stations. The second device connects to a third device, and the third device includes a plurality of access point APs. A first device connects to the third device, and the first device includes one or more STAs. The direct link addressing method includes: receiving a first data unit and parsing the first data unit to obtain a first header. The first header includes a fourth address, a fifth address, and a sixth address. When the first device includes a STA, the fourth address is an address of the second device, the fifth address is an address of the first device, the sixth address is an address of a first AP of the third device, and the first device connects to the first AP of the third device. When the first device includes a plurality of STAs, the fourth address is an address of the second device, the fifth address is an address of the first device, and the sixth address is an address of an AP that corresponds to a sixth direct link and is located in the plurality of APs of the third device, where the sixth direct link is a link for transmitting the first unit of data between the first device and the second device. The first unit of data is transmitted over a direct link between the first device and the second device. In a possible design manner, the direct link addressing method provided in the sixth aspect may further include: parsing the first data unit to obtain a frame body, where the frame body may be a TDLS frame or data. Optionally, the TDLS frame may be a discovery response frame iviA / a / zuzo / u i ut fó TDLS. Furthermore, for a technical effect of the direct link addressing method according to the sixth aspect, reference is made to the technical effect of the direct link addressing method according to the fifth aspect. No details are described again herein. According to a seventh aspect, a direct link addressing method is provided, applied to a second device. The second device includes a plurality of STA stations. The second device connects to a third device, and the third device includes a plurality of access point APs. A first device connects to the third device, and the first device includes one or more STAs. The direct link addressing method includes: determining a first data unit and sending the first data unit. The first data unit includes a first header, and the first header includes a fourth address, a fifth address, and a sixth address. When the first device includes a STA, the fourth address is an address of the first device, the fifth address is an address of the second device, the sixth address is an address of a first AP of the third device, and the first device connects to the first AP of the third device. When the first device includes a plurality of STAs, the fourth address is an address of the first device, the fifth address is an address of the second device, and the sixth address is an address of an AP that corresponds to a sixth direct link and is located in the plurality of APs of the third device, where the sixth direct link is a link for transmitting the first data unit between the first device and the second device. The first unit of data is transmitted over a direct link between the first device and the second device. In one possible design manner, the first data unit further includes a frame body, and the frame body may be a TDLS frame or data. Optionally, the TDLS frame may be a TDLS discovery response frame. Furthermore, for a technical effect of the direct link addressing method according to the seventh aspect, reference is made to the technical effect of the direct link addressing method according to the fifth aspect. No details are described again herein. According to an eighth aspect, a direct link addressing method is provided, applied to a first device. The first device includes one or more STA stations. The first device connects to a third device, and the third device includes a plurality of access point APs. A second device connects to the third device, and the second device includes a plurality of STAs. The direct link addressing method includes: receiving a first data unit and parsing the first data unit to obtain a first header. The first header includes a fourth address, a fifth address, and a sixth address. When the first device includes a STA, the fourth address is an address of the first device, the fifth address is an address of the second device, the sixth address is an address of a first AP of the third device, and the first device connects to the first AP of the third device. When the first device includes a plurality of STAs, the fourth address is an address of the first device, the fifth address is an address of the second device, and the sixth address is an address of an AP that corresponds to a sixth direct link and is located in the plurality of APs of the third device, where the sixth direct link is a link for transmitting the first unit of data between the first device and the second device. The first unit of data is transmitted over a direct link between the first device and the second device. In a possible design manner, the direct link addressing method provided in the eighth aspect may further include: parsing the first data unit to obtain a frame body, where the frame body may be a TDLS frame or data. Optionally, the TDLS frame may be a TDLS discovery response frame. Furthermore, for a technical effect of the direct link addressing method according to the eighth aspect, reference is made to the technical effect of the direct link addressing method according to the fifth aspect. No details are described again herein. According to a ninth aspect, a direct link addressing apparatus is provided. The direct link addressing apparatus includes units or modules configured to perform the method according to any of the first aspect, the fourth aspect, the fifth aspect or the eighth aspect. In this application, the direct link addressing apparatus according to the ninth aspect may be the first device, or a chip (system) or other component or assembly that may be arranged in the first device. Furthermore, for a technical effect of the direct link addressing apparatus according to the ninth aspect, reference is made to the technical effect of the direct link addressing method according to any implementation of the first aspect or the fifth aspect. No details are described again herein. According to a tenth aspect, a direct link addressing apparatus is provided. The direct link addressing apparatus includes units or modules configured to perform the method according to any of the second aspect, the third aspect, the sixth aspect or the seventh aspect. iviA / a / zuzo / ui ut In this application, the direct link addressing apparatus according to the tenth aspect may be the second device, or a chip (system) or other component or assembly that may be arranged in the second device. Furthermore, for a technical effect of the direct link addressing apparatus according to the tenth aspect, reference is made to the technical effect of the direct link addressing method according to any implementation of the first aspect or the fifth aspect. No details are described again herein. According to an eleventh aspect, a direct link addressing apparatus is provided. The direct link addressing apparatus includes a processor, the processor is coupled to a memory, and the memory is configured to store computer programs. The processor is configured to execute the computer programs stored in the memory, so that the direct link addressing apparatus performs the direct link addressing method according to any of the possible implementations of the first aspect to the eighth aspect. In a possible design, the direct link addressing apparatus according to the eleventh aspect may further include a transceiver. The transceiver may be a transceiver circuit or an input / output port. The transceiver can be used by the direct link addressing device to communicate with another device. In this application, the direct link addressing apparatus according to the eleventh aspect may be the first device, the second device, or a chip or a chip system disposed within the first device or the second device. Furthermore, for a technical effect of the direct link addressing apparatus according to the eleventh aspect, reference is made to the technical effect of the direct link addressing method according to any implementation of the first aspect to the eighth aspect. No details are described again herein. According to a twelfth aspect, a communication system is provided. The communication system includes a first device and a second device. According to a thirteenth aspect, a chip system is provided. The chip system includes a processor and an input / output port, the processor is configured to implement processing functions in the first aspect to the eighth aspect, and the input / output port is configured to implement transceiver functions in the first aspect to the eighth aspect. In one possible design, the chip system also includes memory. The memory is configured to store program instructions and data that implement functions in the first aspect to the eighth aspect. The chip system may include a chip, or may include a chip and another discrete component. According to a fourteenth aspect, a computer-readable storage medium is provided, including computer programs or instructions. When computer programs or instructions are executed on a computer, the computer is activated to perform the direct link addressing method according to any of the possible implementations of the first aspect to the eighth aspect. According to a fifteenth aspect, a computer program product is provided, including computer programs or instructions. When computer programs or instructions are executed on a computer, the computer is activated to perform the direct link addressing method according to any of the possible implementations of the first aspect to the eighth aspect. BRIEF DESCRIPTION OF THE FIGURES FIGURE 1 is a schematic diagram of an architecture of a communication system according to an embodiment of this application; FIGURE 2 is a schematic diagram of a structure of an MLD AP and a non-AP MLD participating in communication according to an embodiment of this application; FIGURE 3 is a schematic diagram of a frame structure of a multilink element according to an embodiment of this application; FIGURE 4 is a schematic diagram of a frame structure of a link identifier element according to an embodiment of this application; FIGURE 5 is a schematic diagram of an AAD frame structure according to an embodiment of this application; FIGURE 6 is a schematic diagram of a frame structure of an MPDU according to an embodiment of this application; FIGURE 7 is a schematic flowchart of a direct link addressing method according to an embodiment of the present application; The FIGURES is a schematic diagram of a structure of an MLD AP, a legacy STA and a non-AP MLD 2 participating in communication according to an embodiment of this application; FIGURE 9 is a schematic diagram of a structure of an AP MLD, a non-AP MLD 1 and a non-AP MLD 2 participating in communication according to an embodiment of this application; FIGURE 10 is a schematic diagram of a structure of a non-AP MLD 1 and a non-AP MLD2 participating in communication according to an embodiment of this application; FIGURE 11 is a schematic diagram of a frame structure of an activation scheduling element according to an embodiment of this application; iviA / a / zuzo / u i ut FIGURE 12 is a schematic diagram of a frame structure of another multilink element according to an embodiment of this application; FIGURE 13 is a schematic diagram of a frame structure of a frame body according to an embodiment of this application; FIGURE 14 is a schematic diagram of a frame structure of a TDLS link information element according to an embodiment of this application; FIGURE 15 is a schematic flowchart of another direct link addressing method according to an embodiment of the present application; FIGURE 16 is a schematic flowchart of another direct link addressing method according to an embodiment of the present application; FIGURE 17 is a schematic flowchart of another direct link addressing method according to an embodiment of the present application; FIGURE 18 is a schematic diagram of a structure of a direct link addressing apparatus according to an embodiment of this application; and FIGURE 19 is a schematic diagram of a structure of another direct link addressing apparatus according to an embodiment of this application. DETAILED DESCRIPTION OF THE INVENTION In the descriptions of this application, unless otherwise specified, / means or. For example, A / B can represent A or B. A term and / or in this specification describes only one association relationship between associated objects and indicates that there can be three relationships. For example, A and / or B can indicate the following three cases: Only A exists, both A and B exist, and only B exists. Furthermore, at least one means one or more, and a plurality of means two or more. Terms such as first and second do not limit a quantity and sequence of execution, and terms such as first and second do not indicate a definite difference. All aspects, embodiments or features are presented in this application in describing a system that may include a plurality of devices, components, modules and the like. It should be appreciated and understood that each system may include other devices, components, modules and the like, and / or may not include all of the devices, components, modules and the like discussed with reference to the accompanying drawings. Additionally, a combination of these solutions can be used. In this application, the word such as example or for example is used to represent that an example, illustration or description is given. Any design modality or scheme described as an example or example in this application should not be explained as being more preferred or having more advantages than another design modality or scheme. Exactly, the use of the word such as example or for example is intended to present a related concept in a specific way. A multi-link device (MLD) includes one or more affiliate stations, and the affiliate station is a logical station. “A multilink device includes an affiliate station is also briefly described as A multilink device includes a station in embodiments of this application. The affiliated STA can be an AP station or non-access point (non-AP STA). For ease of description, in this application, a multilink device whose affiliate station is an AP is called an MLD AP, a multilink AP, a multilink AP device, or an access point AP. An individual link device whose affiliate station is an AP is known as an AP device, an access point, an AP, a link AP device, or an individual access point AP. A multilink device whose affiliate station is a non-AP STA is known as a non-AP MLD, multilink STA, multilink STA device, MLD STA, or the like. An individual link device whose affiliate station is a non-AP STA is known as a STA device, a station, a STA, a non-AP STA, or the like. The technical solutions in embodiments of this application can be applied to various communication systems, for example, a system using the IEEE 802.11 standard. For example, the IEEE 802.11 standard includes but is not limited to the 802.11be standard or the 802.11 next generation standard. Scenarios to which the technical solutions in this application are applicable include: communication between a noAP MLD and a MLD AP, communication between a STA device and an MLD AP, communication between a non-AP MLD and a non-AP MLD, and communication between a STA device and a non-AP MLD. The MLD multilink device may implement wireless communication in accordance with IEEE 802.11 serial protocols, for example, in accordance with an extremely high throughput (EHT) protocol, or in accordance with an 802.11 be-based or compatible protocol. with 802.11 be, thus implementing communication with another device. Certainly, the other device may be a multilink device or it may not be a multilink device. A network architecture and service scenario described in embodiments of the present application are intended to describe the technical solutions in embodiments of the present application more clearly, and not to constitute a limitation on the technical solutions provided in embodiments of the present application. A person skilled in the art may know that: With the evolution of network architecture and the emergence of new service scenarios, the technical solutions provided in the embodiments of the present application are also applicable to similar technical problems. To facilitate understanding of the embodiments of this application, a communication system shown in FIGURE 1 is first used as an example to describe in detail a communication system applicable to embodiments of this application. For example, FIGURE 1 is a schematic diagram of an architecture of a communication system to which a direct link addressing method is applicable according to an embodiment of the present application. As shown in FIGURE 1, the communication system includes at least one AP MLD, and at least one non-AP MLD such as a non-AP MLD 1 and a non-AP MLD 2. Optionally, the communication system may further include the least one STA device. The AP MLD may include a plurality of APs, the non-AP MLD may include a plurality of STAs, the STA device includes a STA, and the STA device may be referred to as a legacy STA. The MLD AP is a device that is deployed in a wireless communication network and that provides a wireless communication function for a STA associated with the MLD AP. The MLD AP includes, but is not limited to: an access point (AP) in a wireless fidelity (Wi-Fi) system, such as a local gateway, router, server, a switch and a bridge, an evolved NodeB (eNB), a radio network controller (RNC), a NodeB (NB), a base station controller (BSC) , a base transceiver station (BTS), a local base station (for example, a local evolved NodeB or a local NodeB (HNB), a baseband unit (BBU), a wireless relay node , a wireless backhaul node, a transmission and reception point (TRP; or transmission point, TP) or similar. The MLD AP may alternatively be a gNB or a transmit and receive point (TRP or TP) in a 5G system, for example, a new radio (NR) system, or an antenna panel or a group of panels antenna (including a plurality of antenna panels) of a base station in a 5G system. The MLD AP may alternatively be a network node, such as a baseband unit (BBU), a distributed unit (DU) or a road side unit (RSU) that has a function of base station, which constitutes a gNB or a transmission and reception point. The non-AP MLD or STA device is a terminal that accesses the communication system and has a wireless transceiver function, or a chip or chip system that can be arranged in the terminal. The terminal device may also be called a user apparatus, access terminal, subscriber unit, subscriber station, mobile station, remote station, remote terminal, mobile device, user terminal, terminal, wireless communication device, user agent or user device. The terminal device in embodiments of this application may be a mobile phone, a tablet computer (Pad), a computer that has a wireless transceiver function, a virtual reality (VR) terminal device, a augmented reality terminal device iviA / a / zuzo / u i ut fó (augmented reality, AR), a wireless terminal in industrial control (industrial control), a wireless terminal in autonomous driving (self driving), a wireless terminal in telemedicine (telemedicine ), a wireless terminal in smart electrical network (smart grid), a wireless terminal in transportation safety (transported safety), a wireless terminal in smart city (smart city), a wireless terminal in smart home (smart home), a terminal vehicle-mounted, an RSU that has a terminal function, or the like. Alternatively, the terminal device in this application may alternatively be a vehicle-mounted module, a vehicle-mounted component, a vehicle-mounted chip, or a vehicle-mounted unit that is constructed in a vehicle as one or more components or units. The vehicle may implement the direct link addressing method provided in this application by using the embedded vehicle-mounted module, vehicle-mounted component, vehicle-mounted chip, or vehicle-mounted unit. It should be noted that the direct link addressing method provided in the embodiments of the present application is applicable to any of the two nodes shown in FIGURE 1. For specific implementation, reference is made to the following method embodiments. No details are described herein. It should be noted that, the solutions in the embodiments of this application can also be used in another communication system, and a corresponding name can also be replaced with a name of a corresponding function in the other communication system. It should be understood that FIGURE 1 is simply a simplified schematic diagram of an example for ease of understanding. The communication system may also include another device not drawn in FIGURE 1. A frequency band in which the multilink device operates may include, but is not limited to: sub 1 GHz (sub 1 GHz), 2.4 GHz, 5 GHz, 6 GHz and a high frequency 60 GHz. Additionally, an MLD can be communicate through a plurality of channels in the same frequency band. The plurality of frequency bands or the plurality of channels can be collectively called multilink. A maximum throughput is increased in a multilink communication manner, a service transmission delay is reduced, and a communication rate between MLDs is increased. FIGURE 2 shows a schematic diagram of a structure of an MLD AP and a non-AP MLD participating in the communication. As shown in FIGURE 2, the MLD AP includes an Affiliate AP 1 and an Affiliate AP 2. AP 1 and AP 2 are independent of each other in a low media access control layer. MAC) and a physical layer (PHY), and they share a high MAC layer. The non-AP MLD includes an iviA / a / zuzo / u i ut Affiliated STA 1 and affiliated STA 2. STA 1 and STA 2 are independent of each other at a low MAC layer and a PHY layer, and share a high MAC layer. The MLD AP and non-MLD AP can communicate through Link 1 and Link 2. One end of Link 1 connects to AP 1 of the MLD AP, and the other end of Link 1 connects to STA 1 of the MLD AP. MLD not AP. One end of link 2 connects to AP 2 of the MLD AP, and the other end of link 2 connects to STA2 of the noAP MLD. A multilink device corresponds to a multilink device address, and each link of the multilink device corresponds to a respective link address. The AP MLD is used as an example. The multilink device address can be an MLD AP MAC address. The non-AP MLD is used as an example. The multilink device address may be a STA MLD MAC address. A link address between the MLD AP and the non-AP MLD may include an affiliated AP MAC address and an affiliated STA MAC address corresponding to two ends of a link. It should be noted that FIGURE 2 shows that the MLD AP and the non-AP MLD operate only on the two links. A number of links on which the MLD AP and the non-AP MLD operate are not limited in this embodiment of this application. For example, the multi-link device is a device that has a wireless communication function. The device may be a system-wide device, or it may be a chip, processing system, or the like installed in the system-wide device. The device in which the chip or the processing system is installed may be controlled by the chip or the processing system, to implement the method and functions in embodiments of this application. The following specifically describes the configuration of a plurality of links between the noAP MLD and the MLD AP with reference to FIGURE 2 and FIGURE 3. The non-AP MLD may perform a multi-link configuration operation on one of the links to simultaneously associate a plurality of links of the MLD AP. In an association process, the noAP MLD and the MLD AP can exchange an Association Request / Response frame over a link. One link used to exchange the association request / response frame may be called a transmission link, and another link is a Non-transmission Link. It should be understood that the association request / response frame may carry information about the plurality of links to be associated, to simultaneously associate the plurality of links between the non-AP MLD and the MLD AP. For example, referring to FIGURE 2, the non-AP MLD sends an association request frame over link 1, where the association request frame carries information ΐνΐΛ / 3 / ZUZO / U I U / fo STA of link 1 and STA information of link 2. It should be understood that link 1 can be referred to as a transmission link, and link 2 can be referred to as a non-transmission link. The MLD AP sends an association response frame to the non-AP MLD over link 1, where the association response frame can carry AP information of link 1 and AP information of link 2. Therefore, the non-AP MLD and The MLD AP establishes association over link 1 and link 2. Additionally, the non-AP MLD and the MLD AP can transmit data over link 1 and link 2. To realize a multi-link operation, the related information of the plurality of links can be indicated in a frame related to the multi-link operation. Therefore, a protocol defines a multi-link element. For example, as shown in FIGURE 3, the information carried in the multi-link element is mainly divided into two parts. One part is multilink device level information (MLD level information) that includes fields such as a multilink control field and an MLD MAC address field, and the other part is per station information (Per STA Profile) that carries information related to a non-transmission link. The per-STA profile indicates a link identifier (link ID) of a corresponding link, and the link identifier may indicate information about a STA related through the link corresponding to the per-STA profile. The MLD MAC address field carries an MLD MAC address of a transmitting end. To reduce signaling overheads, the multilink element uses an inheritance structure. When the content of a corresponding element on a non-transmitting link is the same as the content of a corresponding element on a transmitting link, the corresponding element on the non-transmitting link does not need to be carried in a profile per STA of the link. The per-STA profile of the link is carried only when the content of the corresponding element on the non-transmitting link is different from the content of the corresponding element on the transmitting link. It should be noted that a specific format of the multilink element is not limited to that shown in FIGURE 3, and a specific format of a link identifier element is not limited in this application. It should be understood that the non-AP MLD may obtain, upon receipt of a probe response frame or a beacon frame, link information (e.g., a link identifier) ​​corresponding to each link, and may further obtain a channel on which each link functions and an address of each link, for example, a basic service set identifier (BSSID) of the link. The following specifically describes the Tunneled Direct-Link Setup (TDLS) between two STA devices with reference to Table 1 and the iviA / a / zuzo / ui ut FIGURE 4. FIGURE 4 is a schematic diagram of a frame structure of a link identifier element according to an embodiment of this application. It is assumed that both a first STA device and a second STA device are connected to the same AP device, the first STA device includes a STA and the second STA device includes a STA. If the first STA device and the second STA device are within reachable wireless communication range, a direct link can be established between the first STA device and the second STA device, so that the first STA device and the second STA device communicate. They can communicate directly with each other through the direct link without forwarding by using the AP device, thus improving data transmission speed and reducing delay. For example, TDLS-related operations include but are not limited to one or more of the following: TDLS discovery, TDLS configuration, TDLS override, TDLS channel switching, TDLS power saving, and TDLS traffic indication. The TDLS frames corresponding to TDLS-related operations are shown in the following Table 1. In this embodiment of this request, the TDLS frame may include a TDLS action frame and a TDLS public action frame. For example, Referring to the following Table 1, a TDLS Discovery Response frame belongs to the TDLS public action frame, and all TDLS frames except the TDLS discovery response frame belong to the TDLS public action frame. TDLS action. It should be understood that the first STA device and the second STA device may implement corresponding TDLS-related operations by exchanging TDLS frames. For example, the first STA device and the second STA device may implement TDLS power saving by exchanging a TDLS Peer Power Saving Management Request frame (TDLS Peer PSM Request frame) and a TDLS Peer PSM Response frame. Alternatively, the first STA device or the second STA device may implement a corresponding TDLS-related operation by using a TDLS frame. For example, the first STA device may implement TDLS teardown by using a TDLS Teardown frame. A transmission mode of a TDLS frame may include: forwarding through AP (via AP) or direct transmission (direct). Forwarding through AP indicates that a TDLS frame needs to be used in this transmission mode to forward data between the first STA device and the second STA device through the AP. Direct transmission indicates that the TDLS frame in this transmission mode can be transmitted from one STA device to another STA device at iviA / a / zuzo / u i ut fó through a direct link between the STA devices, and no forwarding is required. an AP device. It should be understood that some TDLS frames or a TDLS frame can be transmitted in one or two (both allowed) ways. For details, see the following Table 1. No details are listed here. When the TDLS frame is forwarded through the AP device or sent over the direct link, the TDLS frame is encapsulated into a data frame or management frame for sending. Specifically, the TDLS action frame can be encapsulated into a data frame for sending, and the TDLS public action frame can be sent directly in the form of a management frame. For details, see the following Table 1. No details are listed here. Table 1 TDLS frame Transmission mode Frame type TDLS Discovery Request frame via AP Data frame Direct TDLS Discovery Response frame Management frame TDLS Setup request frame Request frame) via AP Data frame TDLS Setup Response frame via AP Data frame TDLS Setup Confirm frame via AP Data frame TDLS Teardown frame both allowed Data frame Direct TDLS Channel Switch Request frame Data frame Direct TDLS Channel Switch Response frame Data frame Saving management request frame TDLS Peer PSM Request frame Both allowed Data frame Direct TDLS Peer PSM Response frame Data frame TDLS peer traffic indication frame PeerTraffic Indication frame) via AP Data frame Direct TDLS PeerTraffic Response frame Data frame The following describes AAD and an MPDU in the following embodiments of this application with reference to FIGURE 5 and FIGURE 6. As shown in FIGURE 5, AADs can include one or more of the following fields: a frame control field (Frame Control), an addressl field (Addressl), an address2 field (Address2), an address3 field (Address3 ), a sequence control field (Sequence Control), an address4 field (Address4), and a Quality of Service Control (QoS Control) field. Specifically, addressl indicates a receiver address (RA), address2 indicates a transmitter address (TA), and address3 indicates an address of an MLD AP associated with a receiving end, or an address of an AP (an AP in the AP MLD) associated with the receiving end. For a management frame, address3 can be used for frame filtering. For example, you can learn, based on address3, whether the frame belongs to a basic service set (BSS). If the frame does not belong to the basic service set, the frame is discarded. It should be noted that a specific format of the AAD is not limited to that shown in FIGURE 5. For example, address4 in the AAD may be optional. The specific format of the AAD is not limited in this application. As shown in FIGURE 6, the MPDU may include one or more of the following fields: a frame control field, a Duration field, an addressl field, an address2 field, an address3 field, a sequence control, an address4 field, a quality of service control field, a high throughput control (HT Control) field, a block chaining message authentication code protocol header field cipher block chaining message authentication code protocol header (CCMP Header), a Frame Body field, a Message Integrity Code (MIC) field, and a Frame Verification Sequence field (frame check sequence, FCS). Specifically, addressl indicates a receiver address, address2 indicates a transmitter address, and address3 indicates an address of an MLD AP associated with a receiving end, or an address of an AP (an AP in the MLD AP) associated with the receiving end, or an address of an AP (an AP in the AP MLD) associated with a link between a transmitting end and the receiving end. As shown in FIGURE 6, an MPDU header can include: frame control, duration, addressl, address2, address3, sequence control, address4, quality of service control, and stop control. performance. The transmitting end calculates the MIC based on the AAD and the frame body of the MPDU, places the MIC behind the frame body, and then encrypts the frame body of the MPDU and the MIC for transmission. After receiving the MPDU, the receiving end performs a MIC check and calculates iviA / a / zuzo / u i ut a piece of MIC. The receiving end then compares the calculated MIC with the received MIC to check whether the MPDU has been tampered with. It should be noted that a specific format of the MPDU is not limited to that shown in the FIGURES. For example, address4 in the MPDU may be optional. The specific format of the MPDU is not limited in this application. The address configurations of a data frame and a management frame transmitted between a legacy STA and an AP device are described below with reference to Table 2 and Table 3. The AP device may include an affiliated AP. For the data frame and the management frame transmitted between the legacy STA and the AP device, an addressl, an address2, an address3 and an address4 in an MPDU header are correspondingly consistent with an addressl, an address2, an address3 and an address4 in AAD. The specific configurations are shown in Table 2 and Table 3. For example, the addressl, address2, address3, and address4 in the MPDU header of the data frame, and the addressl, address2, address3, and address4 in the AAD are shown in Table 2. In Table 2 , when to distributed system (To distributed system, To DS) = 0 and from distributed system (From DS) = 0, indicates point-to-point (Point-to-Point, P2P), that is, a direct link, and communication is carried out between STA. When To DS = 0 and From DS = 1, it indicates downlink transmission, that is, a DS side sends information to a STA. When To DS = 1 and From DS - 0, it indicates uplink transmission, that is, the STA sends information to the DS side. A DA indicates a destination address (DA), a SAindicates a source address (SA), and a BSSID indicates an address of the affiliated AP of the AP device. The configurations of address3 and address4 are divided into two cases: a MAC Service data unit and short aggregate MAC Service data unit case, MSDU and Short A -MSDU case), and a caseA-basic MSDU and A-dynamic A-MSDU (caseA-basic MSDU and A-dynamic A-MSDU). iviA / a / zuzo / u i ut Table 2 ADS From DS Addressl Address2 Address3 Address4 Case MSDU and short A-MSDU Case Basic AMSDU and dynamic A-MSDU Case MSDU and short A-MSDU Case Basic AMSDU and dynamic A-MSDU 0 0 RA= DA TA= SA BSSID BSSID N / A N / A 0 1 RA TA = BSSID SA BSSID N / A N / A 1 0 RA = BSSID TA DA BSSID N / A N / A 1 1 RA TA DA BSSID N / A BSSID iviA / a / zuzo / ui ut For example, the addressl, address2, and address3 in the MPDU header of the management frame, and the addressl, address2, and address3 in the AAD are shown in Table 3. A MAC address of the STA is an address of the Legacy STA, and a BSSID indicates an address of the affiliated AP of the AP device. Table 3 Frame Type Direction Addressl Address2 Address3 Management Frame Uplink BSSID MAC Address of STA BSSID Downlink MAC Address of STA BSSID BSSID The following describes the address configurations of a data frame and a management frame transmitted between a non-AP MLD and an AP MLD with reference to Table 4 and Table 5. The non-AP MLD may include a plurality of affiliated SSTAs, and the AP MLD may include a plurality of affiliated APs. For example, for the data frame transmitted between the non-AP MLD and the MLD AP, the specific configurations of an addressl, an address2, and an address3 in AAD are shown in Table 4. For the data frame, the addressl and the address2 are set to the corresponding device addresses when the AAD is built. In one case of an MSDU, for uplink data, an address3 is set as a destination address; and for downlink data, address3 is set as a source address. In the case of an A-MSDU, an address 3 is set to an address of the AP MLD. When transmitted over an air interface, an addressl and an address2 in an MPDU header are set to the corresponding link addresses, and an address3 in the MPDU header is set to the same value as address3 in the AAD. Table 4 Frame Type Address Addressl Address2 Ad dress3 MSDU A-MSDU Data frame transmitted between MLD Uplink MAC Address of AP MLD MAC Address of MLD non-AP DA MAC Address of AP MLD Downlink MAC Address of MLD non-AP MAC Address of AP MLD SA AP MLD MAC Address For example, for the management frame transmitted between the noAP MLD and the MLD AP, the specific configurations of an addressl, an address2, and an address3 in AAD are shown in Table 5. It should be noted that in the case of a plurality of links, the management frame can be classified into a link-level management frame (link-level) and an MLD-level management frame (MLD-level). Link level management frame means that the management frame is for a specific link, for example, a channel switching request / response frame. The MLD level management frame is for a complete multilink device, for example, an Add Block ACK (ADDBA) frame. iviA / a / zuzo / ui ut Table 5 Frame Type Address Addressl Address2 Address3 MLD Level Management Frame Uplink MAC Address of AP MLD MAC Address of MLD Non-AP MAC Address of AP MLD Downlink MAC Address of MLD Non-AP MAC Address of AP MLD MAC Address of AP MLD Management Frame link level Uplink MAC Address of MLD AP MAC Address of MLD Non-AP AP Affiliate BSSID Downlink MAC Address of MLD Non-AP AP MAC Address MLD AP Affiliate BSSID The rules for setting addressl, address2 and address3 in the AAD of the management frame and the rules for setting addressl, address2 and address3 in the MPDU header during transmission over the air interface are as follows: For addressl and address2, when the AAD is constructed, addressl and address2 are set to the addresses of the corresponding MLDs; and when transmitted over the air interface, the addressl and address2 in the MPDU header are replaced with the corresponding link addresses. For address3, when the management frame is a link-level management frame, A3 in the AAD is set to an Affiliated AP address corresponding to a destination link. When transmitted over the air interface, A3 in the MPDU header is the same as A3 in the AAD. For the MLD level management frame, A3 in the AAD is set to an MLD AP address. When transmitted over the air interface, A3 in the MPDU header is the same as A3 in the AAD. The following specifically describes the direct link addressing method provided in embodiments of this application with reference to FIGURE 7 to FIGURE 17. For example, FIGURE 7 is a schematic flowchart of a direct link addressing method according to an embodiment of the present application. An example where a first device is used as a TDLS initiator is used for description. The direct link addressing method is applicable to communication between the STA device and the non-AP MLD 2 shown in FIGURE 1 or between the non-AP MLD 1 and the non-AP MLD 2 shown in FIGURE 1. As shown in FIGURE 7, the direct link addressing method includes the following steps. S701: The first device determines the protected data. For example, the first device may include one or more STA stations, the first device connects to a third device, and the third device may include a plurality of APs. When the first device includes a STA, the first device may be the STA device shown in FIGURE 1. The STA device may be referred to as a legacy STA. For ease of understanding, the legacy STA is used as an example for description in the following embodiments of this application. When the first device includes a plurality of STAs, the first device may be the non-AP MLD 1 shown in FIGURE 1. The third device may be the AP MLD shown in FIGURE 1. Protected data may include a first address, a second address and a third address. For example, the protected data may be the AAD shown in FIGURE 5, the first address may be addressl in the AAD, the second address may be address2 in the AAD, and the third address may be address3 in the AAD. In some embodiments, when the first device includes a STA, the first address is an address of a second device, the second address is an address of the first device, the third address is an address of a first AP of the third device and the first device connects to the first AP of the third device. The second device connects to the third device, the second device may include a plurality of STAs, and the second device may be the non-AP MLD 2 shown in FIGURE 1. For example, FIGURE 8 shows an example where the first device is the legacy STA, the second device is the non-AP MLD 2, and the third device is the MLD AP. As shown in FIGURE 8, the MLD AP includes an AP 1, an AP 2, and an AP 3. The legacy STA connects to AP 1 of the MLD AP, and a STA 1 and a STA 2 of the MLD non-AP 2 are connected. They connect respectively to AP 1 and AP 2 of the MLD AP. As shown in Table 6, the first address is a non-AP MLD 2 address, for example, a non-AP MLD 2 MAC address; the second address is an address of the legacy STA, for example, a MAC address of the legacy STA; and the third address is an address of AP 1, for example, a BSSID of AP 1. Table 6 iviA / a / zuzo / u i uz fo Scenario Protected data First address Second address Third address (legacy STA, noAP MLD 2) MAC address of noAP MLD 2 MAC address of legacy STA BSSIDdelAP 1 iviA / a / zuzo / u i ut fo In some embodiments, when the first device includes a plurality of STAs, the first address is an address of the second device, the second address is an address of the first device, and the third address is an address of the third device. Table 7 Scenario Protected data First address Second address Third address (MLD noAP 1, MLD noAP2) MAC address of MLD noAP 2 MAC address of MLD noAP 1 MAC address of AP MLD For example, FIGURE 9 shows an example in which the first device is the non-AP MLD 1, the second device is the non-AP MLD 2, and the third device is the MLD AP. As shown in FIGURE 9, the MLD AP includes an AP 1, an AP 2 and an AP 3, a STA 1 and a STA 2 of the MLD non-AP 1 respectively connect to AP 1 and AP 3 of the MLD AP, and a STA 1 and a STA 2 of the MLD non-AP 2 are respectively connected to the AP 1 and AP 2 of the MLD AP. As shown in Table 7, the first address is an address of the non-AP MLD 2, for example, the MAC address of the non-AP MLD 2; the second address is an address of the MLD non-AP 1, for example, the MAC address of the MLD non-AP 1; and the third address is an address of the MLD AP, for example, the MAC address of the MLD AP. It should be noted that FIGURE 8 and FIGURE 9 are merely examples provided in this form of this application. A number of STAs included in the non-AP MLD 2 and a number of APs included in the MLD AP are not limited, and how the non-AP MLD 2 connects to the MLD AP and how the legacy STA connects to the MLD AP are not limited . S702: The first device sends a first unit of data. Correspondingly, the second device receives the first data unit from the first device. The first data unit may include a first header, the first header is determined based on the protected data, and the first data unit is transmitted over a direct link between the first device and the second device. For example, the first data unit may be the MPDU shown in FIGURE 6, and the first header may be the MPDU header shown in FIGURE 6. Referring to FIGURE 9, the first data unit can be transmitted over a link 1 between the first device and the second device, and does not need to be forwarded by the second device, thus reducing a transmission delay. Optionally, before or in a process in which the first device sends the first data unit in S702, the first data unit may be determined. Specifically, one or more of the following Ways 1 to Way 4 may be used. Way 1: The first device determines the first header of the first data unit. Optionally, the first header may include a fourth address, a fifth address, and a sixth address. For example, the first header may be the MPDU header shown in FIGURE 6. The fourth address may be addressl in the MPDU header, the fifth address may be address2 in the MPDU header, and the sixth address may be address3 in the MPDU header. In some embodiments, when the first device includes a STA, the fourth address is an address of the second device, the fifth address is an address of the first device, and the sixth address is an address of the first AP of the third device. For example, FIGURE 8 shows an example where the first device is the legacy STA, the second device is the non-AP MLD 2, and the third device is the MLD AP. As shown in FIGURE 8, the MLD AP includes an AP 1, an AP 2, and an AP3, the legacy STA connects to AP 1 of the MLD AP, and a STA 1 and a STA 2 of the MLD non-AP 2 connect respectively to AP 1 and AP 2 of the MLD AP. When the first device sends the first data unit to the second device, the address settings on the first data unit are shown in Table 8. The fourth address is an address of the non-AP MLD 2, for example, a MAC address of the Non-AP MLD 2. The fifth address is a legacy STA address, for example, a legacy STA MAC address. The sixth address is an address of AP 1, for example, a BSSID of AP 1. The fourth address, the fifth address and the sixth address in the first header may be respectively the same as the first address, the second address and the third address in the protected data. Table 8 iviA / a / zuzo / u i ut fo Scenario First header Fourth address Fifth address Sixth address (legacy STA, noAP MLD 2) MAC address of noAP2 MLD Legacy STA MAC address BSSID of AP 1 In some embodiments, when the first device includes a plurality of STAs, the fourth address is an address of a STA that corresponds to a first direct link and is located in the plurality of STAs of the second device, the fifth address is an address of a STA corresponding to the first direct link and located in the plurality of STAs of the first device, the sixth address is an address of an AP corresponding to the first direct link and located in the plurality of APs of the third device, and The first direct link is a direct link between the first device and the second device. For example, FIGURE 9 and FIGURE 10 show an example in which the first device is the MLD non-AP 1, the second device is the MLD non-AP 2, and the third device is the AP MLD. As shown in FIGURE 9, a link 1-1 and a link 3 are configured between the first device and the third device, and a link 1-2 and a link 2 are configured between the second device and the third device. As shown in FIGURE 10, a STA 1 of the non-AP MLD 1 connects to a STA 1 of the non-AP MLD 2, and corresponds to a direct link 1. When the first device sends the first data unit to the second device, The address configurations in the first data unit are shown in Table 9. The fourth address is an address of the STA 1 of the non-AP MLD 2, for example, a MAC address of the affiliated STA 1 of the non-AP MLD 2. The fifth address is an address of the STA 1 of the non-AP MLD 1, for example, a MAC address of the affiliated STA 1 of the non-AP MLD 1. The sixth address is an address of an AP 1 corresponding to link 1, for example, a BSSID of the affiliated AP 1 of the MLD AP or a MAC address of the affiliated AP 1 of the MLD AP. It should be noted that, when there is a plurality of direct links between the first device and the second device, the first direct link may be a direct link for transmitting the first data unit on the direct links between the first device and the second device. Table 9 iviA / a / zuzo / u i ut fo Scenario First header Fourth address Fifth address Sixth address (noAP MLD 1, noAP MLD 2) MAC address of STA 1 non-AP2 MLD affiliate MAC address of STA 1 non-AP MLD affiliate 1 BSSID of AP 1 MLD AP affiliate Way 2: The first device determines a first element of the first data unit. Specifically, the first data unit may include a TDLS frame, and the TDLS frame includes the first element. The first element may indicate an identifier (ID) of a target link or an address of an AP that corresponds to the target link and is located in the plurality of APs of the third device. For example, the first element can be set to a BSSID corresponding to the target link. Optionally, the TDLS frame may be a TDLS channel switching request frame or a TDLS channel switching response frame. The third device is assumed to include AP 1, AP 2, and AP 3, and AP 2 corresponds to the target link. In this case, the address of the AP corresponding to the target link and located in the plurality of APs of the third device is an address of the AP 2 of the third device, that is, a BSSID of AP 2 affiliated with the MLD AP. Optionally, the target link is a second direct link to which the TDLS frame is applied, and the second direct link is a direct link between the first device and the second device. It is assumed that there is a direct link 1 and a direct link 2 between the first device and the second device, the TDLS frame is a TDLS channel switching request frame or a TDLS channel switching response frame, and a target link corresponding to the TDLS channel switching request / response frame is direct link 2, direct link 2 can be switched from a current channel to a specified channel based on a first element corresponding to the switching request / response frame TDLS channel. In a multilink TDLS scenario, the first element indicates the target link, and the TDLS channel switching request / response frame can be transmitted over any direct link, rather than necessarily being transmitted over the target link it is going to. to switch the TDLS channel switching request / response frame, thereby improving transmission flexibility. Optionally, the first element can be the Link Identifier element shown in FIGURE 4 or a newly defined element. In some embodiments, a first field in the first element may indicate the identifier of the target link or the address of the AP that corresponds to the target link and is located on the plurality of APs of the third device. For example, the first field may be a BSSID field of the link identifier element. Way 3: The first device determines a second element from the first data unit. Specifically, the first data unit may include a TDLS frame, and the TDLS frame may include a trigger scheduling element and the second element. An offset field in the activation scheduling element is an offset with respect to a first timing synchronization function threshold of a third direct link, the second element indicates an identifier of the third direct link or an address of a corresponding AP to the third direct link and which is located in the plurality of APs of the third device, and the third direct link is a direct link between the first iviA / a / zuzo / u i ut device and the second device. It is assumed that there is a direct link 1 and a direct link 2 between the first device and the second device, the third device includes an AP 1, an AP 2 and an AP 3, the direct link 1 corresponds to AP 1, the direct link 2 corresponds to AP 2 and the offset field in the activation scheduling element is an offset with respect to a first timing synchronization function threshold of the direct link 2. In this case, the second element indicates an identifier of the direct link 2 or an AP 2 address of the third device, for example, an AP 2 BSSID affiliated with the AP MLD. Different affiliated APs of the MLD AP can have independent timing synchronization functions (TSF). In this way, the offset field in the activation scheduling element can be determined to be relative to a TSF of a specific direct link by using an identifier or an address indicated by the second element. Optionally, the TDLS frame may be a TDLS peer power saving management request frame or a TDLS peer power saving management response frame. In this way, after a TDLS initiator and a TDLS responder exchange a TDLS peer power saving management request frame and a TDLS peer power saving management response frame, the TDLS initiator and the TDLS responder They may periodically wake up and receive / send data based on a wake-up scheduling element carried in the TDLS peer power saving management request frame and / or the TDLS peer power saving management response frame, thus reducing energy consumption. Furthermore, the third direct link is indicated with respect to the offset field, so that in the multilink TDLS scenario, the PSM request / response frame of TDLS peers can be transmitted over any direct link, and one end can correctly parse the activation scheduling element, thereby improving transmission flexibility. Optionally, the second element can be the Link Identifier element shown in FIGURE 4 or a newly defined element. In some embodiments, a first field in the second element may indicate the identifier of the third direct link or the address of the AP that corresponds to the third direct link and is located in the plurality of APs of the third device. For example, the first field may be a BSSID field of the link identifier element. Optionally, the activation schedule element may reuse an existing activation schedule element, or may be a newly defined element. For example, with reference to FIGURE 11, the Wakeup Schedule element iviA / a / zuzo / u i ut (Wakeup Schedule element) may include one or more of the following fields: an element ID field, a length field , an Offset field, an Interval field, an Awake window Slots field, a Maximum Awake Window Duration field, and a idle count (Idle Count). The offset field may indicate an offset of a first active window with respect to a TSF 0. The TSF may be a counter, and a value stored in the counter represents a time value. The interval field can indicate a time interval between two adjacent active windows. The active window slot field indicates the duration of an active window. The Maximum Active Window Duration field indicates the maximum duration of an active window. The idle count field indicates a number of active idle windows that are allowed to pass before a TDLS peer end clears the periodic wakeup schedule. Active idle window means that no unicast frame is received from the TDLS peer end in the active window. For example, if the first device does not receive a unicast frame from the second device in a process in which the first device goes through the number of active windows indicated by the idle count field, the second device may remove the scheduling element from activation. It should be noted that Way 2 and Way 3 can be used independently or in combination. When used in combination, the first element and the second element may be the same element, for example, the first element, such that the first element may indicate the identifier of the target link or the address of the AP that corresponds to the target link and which is located in the plurality of APs of the third device, and may indicate the identifier of the third direct link or the address of the AP that corresponds to the third direct link and which is located in the plurality of APs of the third device. In other words, the target link and the third direct link are the same direct link. For different TDLS frames, the following describes a way of configuring the above link identifier element or a newly defined element with reference to Table 10. In other words, when TDLS frames are different frames, the link identifier element, the newly defined, the BSSID field in the link identifier element or a first field of the newly defined element may correspond to different configured content. For ease of description, the link identifier element, the newly defined element, the first element, and the second element are referred to collectively as the first element below. iviA / a / zuzo / u i ut fo In some scenarios, when the first device includes a STA, and the TDLS frame is a TDLS discovery request frame, the first element indicates an identifier of a broadcast link or an address of an AP that corresponds to the broadcast link and that is located in the plurality of APs of the third device. The broadcast link is a link to send the TDLS discovery request frame. For example, the first element can be set to a BSSID corresponding to the broadcast link. When the first device includes a STA, and the TDLS frame is a TDLS discovery response frame, the first element indicates an identifier of a transmission link or an address of an AP that corresponds to the transmission link and is located on the plurality of APs of the third device. The transmission link is an iviA / a / zuzo / u i ut fó link to send the TDLS discovery request frame. Table 10 TDLS Frame Transmission Mode Frame Type Note First Element Legacy STA and Non-AP2 MLD Non-AP MLD 1 and Non-AP MLD 2 TDLS Discovery Request Frame Via AP Data Frame MLD Level Set to the BSSID corresponding to the transmission link Set to a BSSID corresponding to a reference link Direct TDLS discovery response frame Management frame Allow unsolicited sending MLD level Set to a BSSID corresponding to the broadcast link to send the TDLS discovery request frame Set to a BSSID corresponding to a common link to transmit the TDLS discovery response frame (TDLS discovery response frame can be transmitted over any common link) TDLS configuration request frame Via AP Data frame MLD level Set to a BSSID of a link on which the legacy STA is located Set to a BSSID corresponding to a reference link, and a BSSID in the TDLS configuration request / response / confirm frame remains unchanged TDLS configuration response frame A viaAP Data frame MLD level Set to a BSSID of a link on which the legacy STA is located Configuration confirmation frame ViaAP Data frame MLD level Set to a BSSID of a link on which the legacy STA is located TDLS finds inherited STA TDLS override frame Both allowed Data frame MLD level; and if a direct link is unreachable, forwarding is performed by an AP Set to a BSSID of a link on which the legacy STA is located Set to a MAC address of the AP MLD Channel Switching Request Frame TDLS Direct Data Frame Link Level Set to a BSSID of a link on which the legacy STA is located Set to the BSSID corresponding to the target link Channel Switching Response Frame TDLS Direct Data Frame Link Level Set to a BSSID of a link on which the legacy STA is located where the legacy STA is located Set to the BSSID corresponding to the target link TDLS peer power saving management request frame Both allowed Data frame MLD level Set to a BSSID of a link where the legacy STA is located Set to a BSSID of the third direct link corresponding to the activation scheduling element TDLS Direct Peer Power Saving Management Response Frame Data Frame MLD Level Set to a BSSID of a link on which the legacy STA is located Set to a BSSID of the third direct link corresponding to the activation scheduling element TDLS peer traffic indication frame Via AP Data frame MLD level Set to a BSSID of a link on which the legacy STA is located Set to the address of the third device, for example, an AP MAC address MLD Peer traffic response frame TDLS Direct Data frame MLD level Set to a BSSID of a link on which the legacy STA is located Set to the address of the third device, for example, an address MAC of AP MLD In other words, the configured content of the first element corresponding to the iviA / a / zuzo / u i ut fó TDLS frame which is a TDLS discovery response frame is the same as the configured content of the first element corresponding to the TDLS frame which is a TDLS discovery request frame. For example, the first element may be set to the BSSID corresponding to the transmission link to send the TDLS discovery request frame. When the first device includes a STA, and the TDLS frame is a TDLS configuration request frame, the first element indicates an identifier of a link between the first device and the third device, or an address of an AP that corresponds to the first device. and which is located in the plurality of APs of the third device. The broadcast link is a link to send the TDLS discovery request frame. For example, the first element can be set to the BSSID corresponding to the link on which the legacy STA is located. When the first device includes a STA, and the TDLS frame is a TDLS configuration response frame, a TDLS configuration confirmation frame, a TDLS abort frame, a TDLS channel switching request frame, a TDLS channel switching, a TDLS peer power saving management request frame, a TDLS peer power saving management response frame, a TDLS peer traffic indication frame, or a TDLS peer power saving management response frame. TDLS pairs, for a specific implementation of the first element, see the previous implementation of the first element when the first device includes a STA and the TDLS frame is a TDLS configuration request frame. No details are described again herein. In some other scenarios, when the first device includes a plurality of STAs, and the TDLS frame is a TDLS discovery request frame, the first element indicates the identifier of the reference link or an address of an AP that corresponds to the reference link and which is located in the plurality of APs of the third device. Optionally, the reference link may be a link indicated by the BSSID field in the link identifier element. For example, the first element can be set to the BSSID corresponding to the referral link. When the first device includes a plurality of STAs, and the TDLS frame is a TDLS discovery response frame, the first element indicates an identifier of the common link for transmitting the TDLS discovery response frame, or an address of an AP that corresponds to the common link to transmit the TDLS discovery response frame and which is located on the plurality of APs of the third device. The common link is a common link of a link between the first device and the third device and a link between the second device and the third device, and an AP of the third device associated with an STA of the first device corresponding to the common link is the same as an AP of the third device associated with a STA of the second device corresponding to the common link. Optionally, when the first device includes a plurality of STAs, the TDLS discovery response frame may be transmitted over any common link. When the first device includes a plurality of STAs, and the TDLS frame is a TDLS configuration request frame, a TDLS configuration response frame, or a TDLS configuration confirmation frame, the first element indicates the reference link identifier, or the address of the AP that corresponds to the reference link and that is located in the plurality of APs of the third device. For example, the first element can be set to the BSSID corresponding to the referral link. When the first device includes a plurality of STAs, and the TDLS frame is a TDLS override frame, the first element indicates an address of the third device, and may indicate the override of all direct links between the first device and the second device. For example, the first item can be set to the MAC address of AP MLD. Alternatively, the first element indicates an address of an AP that corresponds to the direct link between the first device and the second device and that is located in the plurality of APs of the third device, for example, a BSSID corresponding to a direct link. For example, when the first element is set to an address of an affiliated AP corresponding to a direct link between the first device and the second device, it indicates that the direct link is broken, that is, data cannot be subsequently received or sent. through the direct link. When the first device includes a plurality of STAs, and the TDLS frame is a TDLS channel switching request frame or a TDLS channel switching response frame, for a specific implementation of the first element, refer to Way 2 above. No details are described again herein. For example, the first element can be set to the BSSID corresponding to the target link. When the first device includes a plurality of STAs, and the TDLS frame is a TDLS peer power saving management request frame or a TDLS peer power saving management response frame, for a specific implementation of the first element , refer to Way 3 above. No details are described again herein. For example, the first element may be set to the BSSID of the third direct link corresponding to the activation scheduling element. When the first device includes a plurality of STAs, and the TDLS frame is a TDLS peer traffic indication frame or a TDLS peer traffic response frame, the first element indicates the address of the third device. For example, the first iviA / a / zuzo / u i ut fo element can be set to the MAC address of AP MLD. The following describes the reference link, broadcast link and common link in detail. Reference Link: When the frame body of the MPDU carries the multilink element, a link indicated by the BSSID field in the link identifier element is known as a reference link. For example, for the specific format of the MPDU, reference is made to FIGURE 6. For the specific format of the multilink element, reference is made to FIGURE 3 or FIGURE 12. For a specific format of the link identifier element, reference is made to FIGURE 4. Specifically, for multilink TDLS configuration, when the first device includes a plurality of STAs, it may be necessary to transport a multilink element in the following TDLS action frames: a TDLS configuration request / response frame or a TDLS configuration request / response frame. TDLS discovery. After a TDLS initiator and a TDLS responder successfully exchange a TDLS discovery request / response frame, a non-AP MLD knows whether a peer endpoint is an MLD. When both the TDLS initiator and the TDLS responder are MLD, a multilink element may be carried in a subsequent TDLS configuration request / response frame. FIGURE 12 is a schematic diagram of a frame structure of another multilink element according to an embodiment of this application. As shown in FIGURE 12, a type subfield is set to a number corresponding to TDLS. A Transparent / non-transparent transmission bit indicates an addressing mode used by the non-AP MLD. When the address mode is transparent, it indicates that a non-AP MLD link address is the same as a non-AP MLD address. When the address mode is not transparent, it indicates that different links corresponding to the non-AP MLD use different link addresses, and the non-AP MLD address is different from the link addresses of the non-AP MLD. In this case, a corresponding link ID and an address used by an affiliated STA, i.e. a link address, must be indicated at the beginning of each profile per STA. An MLD MAC address field is always set to the MLD AP MAC address. For a specific format of the frame body, reference is made to FIGURE 13. The frame body may include information about one reference link (such as an element ID #1 and an element ID #2) and information about another link (multilink element). For example, with reference to FIGURE 3 or FIGURE 12, information about the other link may be carried in a profile by STA in the multilink element. Transmission Link: Indicates a link on which a frame is sent. The corresponding link is known as a transmission link. It is assumed that an iviA / a / zuzo / ui ut TDLS frame is sent over link 1, link 1 is known as a transmission link. For a TDLS frame (for example, a TDLS discovery response) encapsulated in a management frame and transmitted directly, a transmission link is a reference link. Specifically, when the management frame is sent, the transmission link is generally required to be consistent with the reference link. For example, if an initiator sends a multilink association request frame over link 1, a responder also needs to return a multilink association response frame over link 1. For a TDLS frame encapsulated in a data frame, a transmission link may be different from a reference link. Specifically, when the data frame is sent, the transmission link can be any link, in other words, the data frame can be sent over any link. Therefore, the transmission link may be the same or different from the reference link. For example, a way to send the data frame may include: One possibility is that the data frame is sent according to a management frame sending requirement, to be specific, the data frame is sent back to through a link that is sent. Furthermore, the transmission link is consistent with the reference link. The other possibility is that the data frame is sent according to a data frame sending requirement, to be specific, the data frame is transmitted over any link. For example, a TDLS configuration request frame is sent over link 1, and a TDLS configuration response frame is sent over link 2. In this case, the transmission link does not need to be consistent with the referral link. Common Link: A direct link corresponding to two STAs (STA refers to a legacy STA or an affiliated STA of a non-AP MLD) associated with the same affiliated AP can be called a common link. For a scenario (legacy STA, MLD), a link associated with the legacy STA is a common link. For a scenario (non-AP MLD 1, non-AP MLD 2), a plurality of common links may exist. For example, assume that AP MLD corresponds to a link 1, link 2, and link 3, link 1 and link 2 are configured between non-AP MLD 1 and AP MLD, and link 1 and link 3 are configured between the non-AP MLD 2 and the MLD AP. Both a STA 1 of non-AP MLD 1 and a STA 1 of non-AP MLD 2 are associated with an AP 1 of the MLD AP, and correspond to link 1. A STA 2 of non-AP MLD 1 is associated with an AP 2 of the AP MLD and corresponds to link 2. A STA 3 of the MLD non-AP 2 is associated with an AP 3 of the MLD AP, and corresponds to link 3. A direct link 1 and a direct link 2 are established, the STA 1 of the MLD non-AP 1 and STA 1 of MLD non-AP 2 correspond to direct link 1, and STA 2 of MLD non-AP 1 and iviA / a / zuzo / u i ut fo STA 3 of MLD non-AP 2 correspond to direct link 2. In this case, direct link 1 can be referred to as a common link. Way 4: The first device determines a third element of the first data unit. Optionally, the first data unit may include the third element, and the third element may indicate configuring at least a fourth direct link on a first link. The first link is a common link of the link between the first device and the third device and the link between the second device and the third device, and the first link may include the at least a fourth direct link. In other words, the first link may be a common link between the first device and the third device and between the second device and the third device, and an AP of the third device associated with a STA of the first device corresponding to the first link is the same than an AP of the third device associated with a STA of the second device corresponding to the first link. In this way, the first device and the second device can establish a direct link on the common link, to increase a data transmission rate. In some embodiments, the third element may include a number of direct link fields and a direct link identifier field. The number of direct links field can indicate a number of fourth requested direct links to be configured. In this way, the number of fourth direct links to be established is indicated, so that the fourth direct link can be established on some or all of the links of the first link, thus improving the flexibility of establishing a direct link. Specifically, the direct link identifier field may include an address of at least one AP that separately corresponds to the at least one fourth direct link and is located in the plurality of APs of the third device, or an identifier of the at least one fourth direct link. In other words, the direct link identifier field may include a BSSID of the at least one AP that separately corresponds to the at least a fourth direct link and is located in the plurality of APs of the third device, or a link ID of at least a fourth direct link. In this way, links can be indicated in which direct links are configured. It should be noted that, in embodiments of this application, the MAC address of the AP, the BSSID of the AP and the address of the AP may express the same meaning when a difference between the MAC address of the AP, the BSSID of the AP and the address is not emphasized. of the AP. Alternatively, optionally, the forward link identifier field may include an address of a first STA of the first device and an address of a second STA iviA / a / zuzo / u i ut of the second device. In other words, the forward link identifier field may include addresses of affiliated STAs at two ends of the forward link, for example, a MAC address of the first STA or a MAC address of the second STA. Alternatively, optionally, the direct link identifier field may include the address of the at least one AP that separately corresponds to the at least one fourth direct link and is located in the plurality of APs of the third device or the identifier of the at least a fourth direct link, the address of the first STA of the first device and the address of the second STA of the second device. The third element above in Way 4 is described by using a scenario where a direct link is established on the common link. In a possible design solution, a direct link can be established on a non-common link between the first device and the second device. When the direct link is established on the non-common link, an implementation of the third element is similar to a specific implementation of the third element corresponding to a scenario in which a direct link is established on the common link. For example, the third element may indicate configuring at least a fifth direct link on a second link. The second link is a link other than the link between the first device and the third device and the link between the second device and the third device, and the second link may include the at least a fifth direct link. In other words, the second link may be a non-common link between the first device and the third device and between the second device and the third device, and an AP of the third device associated with a STA of the first device corresponding to the second link is different of an AP of the third device associated with a STA of the second device corresponding to the second link. In this way, the first device and the second device can establish a direct link on the non-common link, to increase a data transmission rate. In some embodiments, the third element may include a number of direct link fields and a direct link identifier field. The number of direct links field can indicate a number of fifth direct links requested to be configured. In this way, the number of fifth direct links to be established is indicated, so that the fifth direct link can be established on some or all of the links of the second link, thereby improving the flexibility of establishing a direct link. Specifically, the direct link identifier field may include an address of at least one AP that separately corresponds to the at least one fifth direct link and is located in the plurality of APs of the third device, or an identifier of the at least one fifth direct link. For example, one end of the fifth direct link corresponds to a STA ΐνΐΛ / 3 / ZUZO / U I U / fo of the first device, and the other end of the fifth direct link corresponds to a STA of the second device. The forward link identifier field may include an address of an AP that corresponds to the STA of the first device and is located in the plurality of APs of the third device, or an address of an AP that corresponds to the STA of the second device and which is located in the plurality of APs of the third device. In other words, the direct link identifier field may include a BSSID of an affiliated AP corresponding to either end of the fifth direct link or an identifier of the second link corresponding to the affiliated AP. Alternatively, an indirect link can be represented by using an address of an affiliated AP corresponding to an initiator that establishes the direct link or an identifier of the second link corresponding to the affiliated AP. For example, when the first device initiates the direct link configuration, the direct link identifier field may include the address of the AP that corresponds to the STA of the first device and is located in the plurality of APs of the third device, or the identifier of the second link corresponding to the affiliated AP. In some embodiments, the third element may be a TDLS link information element (TDLS link information element). As shown in FIGURE 14, the TDLS link information element may include one or more of the following fields: an element ID field, a length field, a Number of Direct links field and a Direct link Identifier field. It should be noted that a format of the third element is not limited in this embodiment of this application, and Figure 14 is merely an example of this application. It should be noted that Way 1 to Way 4 above can be used in combination with the direct link addressing method shown in FIGURE 7, or Way 1 to Way 4 above can be used independently or in combination between Yeah. This is not limited in this application. In some embodiments, a seventh address is attached to a TPK. Optionally, the seventh address includes an address of an AP that corresponds to the direct link between the first device and the second device and that is located in the plurality of APs of the third device or addresses of all APs of the third device, and the address of the third device. In other words, an address of an affiliated AP (for example, a BSSID of the affiliated AP) corresponding to the direct link and the address of the third device can be linked to the TPK, or the addresses of all affiliated APs (for example, BSSID of all affiliated APs) of the third device and the address of the third device can be linked to the TPK. Optionally, when the first device includes a plurality of STAs, the first iviA / a / zuzo / u i ut device and the second device may negotiate to establish a direct link on some or all of the links, to bind an address of a corresponding affiliated AP to the established direct link and the address of the third device to the TPK, or bind the addresses of all affiliated APs of the third device and the address of the third device to the TPK. In this way, the security of communication between the first device and the second device through the direct link can be improved. In some embodiments, the direct link addressing method provided in this embodiment of this application may further include a TPK bypass process shown in the following step 1 and step 2. It should be noted that step 1 and step 2 are They can be used independently, or they can be used in combination with the method, Way 1, Way 2, Way 3 and / or Way 4 shown in FIGURE 7. Step 1: The first device negotiates with the second device to determine an authentication and key management (AKM) set selector. For example, as shown in Table 11, the AKM suite selector can include one or more of the following: an organizationally unique identifier (OLII), a suite type, authentication, key management, key derivation, and an authentication number. For the specific corresponding content of each article, please refer to Table 11. No details are described herein. Table 11 iviA / a / zuzo / u i ut fo OUI Set Type Authentication Key Management Key Derivation Authentication Number 00-0F-AC 23 Multi-Link TDLS (ML-MLD-TDLS) MLD Multi-Link TPK Handshake (MLD Peer-to-Peer MLTPK) Defined in 12.7. 1.6.2 (Defined in 12.7.1.6.2) Not applicable (N / A) Step 2: The first device negotiates with the second device to derive the TDLS TPK pair key. Optionally, the TPK can be determined by using the following formula (1) and formula (2): TPK-Key-lnput = Hash(min (SNonce, ANonce) || max (SNonce, ANonce)) (1), where in Formula (1) above, Hash represents a hash algorithm, SNonce (requester nonce) represents a random number of the requester, ANonce (authenticator nonce) represents a random number of the authenticator, || represents concatenation or inclusion, a mathematical symbol min represents taking a minimum value and a mathematical symbol max represents taking a maximum value; and TPK = KDF-Hash-Length(TPK-Key-lnput, TDLS MLD PMK, min (MACJ, MAC_R) || max (MACJ, MAC_R) || AP MLD MAC Address || Affiliated AP Addressl || .... Affiliated AP Addressn) (2), where in Formula (2) above, TPK represents the TDLS pair key, KDF-Hash-Length represents a key derivation function, TDLS MLD PMK represents a pairwise TDLS MLD master key master key, PMK), || represents concatenation or inclusion, a mathematical symbol min represents taking a minimum value, a mathematical symbol max represents taking a maximum value, the AP MLD MAC Address represents the address of the third device (AP MLD), and the Affiliated AP Address 1 represents an address of an affiliated AP (a third device AP) corresponding to the direct link between the first device and the second device. When the first device is an initiator, MACJ represents a MAC address of the first device and MAC_R represents a MAC address of the second device. It is noted that the above step 1 and step 2 can also be applied to pairwise master key (PTK) derivation, and the seventh address can be linked to the PTK. No details are described again herein. In some embodiments, the first device and the second device may complete the TPK bypass handshake negotiation by exchanging a TDLS configuration request / response / confirm frame (for details, see step a to step c below). To be specific, the above step 1 and step 2 can be used in combination with the following step a to step c to complete the negotiation of the TPK bypass exchange protocol. An example is used where the first device is used as a TDLS initiator. Step a: The first device sends a TDLS configuration request frame to the second device. Correspondingly, the second device receives the TDLS configuration request frame from the first device. Step b: The second device sends a TDLS configuration response frame to the first device. Correspondingly, the first device receives the TDLS configuration response frame from the second device. Optionally, the second device may send the TDLS configuration iviA / a / zuzo / u i ut response frame to the first device based on a link identifier element and / or a TDLS link information element. For example, the TDLS configuration response frame may include accepting a TDLS configuration request or not accepting a TDLS configuration request. For example, a status code (Status Code) in the TDLS configuration response frame indicates accept or not accept. Step c: If the TDLS configuration response frame indicates Accept, the first device sends a TDLS configuration confirmation frame to the second device to complete the TPK bypass handshake negotiation. According to the direct link addressing method described in FIGURE 7, when the first device includes a STA, the protected data is constructed by using the address of the first device, the address of the second device, and the address of the first AP connected to the first device. When the first device includes a plurality of STAs, the protected data is constructed by using the address of the first device, the address of the second device, and the address of the third device. Therefore, the first device can transmit the first unit of data through the direct link between the first device and the second device, thereby increasing a data transmission rate. Furthermore, when the first device includes a plurality of STAs, the protected data is constructed by using the addresses of the devices, and a change of the direct link does not affect the protected data. Therefore, when data is transmitted over a plurality of direct links, encryption does not need to be performed again, which further increases the data transmission speed. For example, FIGURE 15 is a schematic flowchart of another direct link addressing method according to an embodiment of the present application. An example where a second device is used as a TDLS initiator is used for description. The direct link addressing method is applicable to communication between the STA device and the non-AP MLD 2 shown in FIGURE 1 or between the non-AP MLD 1 and the non-AP MLD 2 shown in FIGURE 1. S1501: The second device determines the protected data. The protected data includes a first address, a second address and a third address. In some embodiments, when the first device includes a STA, the first address is an address of a second device, the second address is an address of the second device, the third address is an address of a first AP of a third device, and the first device connects to the first AP of the third device. Referring to the FIGURES, when the first device includes a STA and the second iviA / a / zuzo / ui ut device is used as a TDLS initiator, the first address, the second address and the third address of the protected data are shown in Table 12 A difference from Table 6 in S701 is that the configured content of the first address and the configured content of the second address are exchanged, and a responder is the first device, so that the first address is an address of a STA. legacy, for example, a legacy STA MAC address; and the initiators the second device, so that the second address is a non-AP MLD 2 address, for example, a non-AP MLD 2 MAC address. The third address is the same as the third address in Table 6, and the third address is an address of an AP 1, for example, a BSSID of AP 1. Table 12 iviA / a / zuzo / u i ut Scenario Protected data First address Second address Third address (legacy STA, noAP2 MLD) legacy STA MAC address noAP2 MLD MAC address BSSID of AP 1 In some embodiments, when the first device includes a plurality of STAs, the first address is an address of the first device, the second address is an address of the second device, and the third address is an address of the third device. Referring to FIGURE 9, when the first device includes a plurality of STAs, and the second device is used as the TDLS initiator, the first address, the second address and the third address of the protected data are shown in Table 13. Due Since the initiator and a responder change, a difference between Table 13 and Table 7 in S701 is that the configured content of the first address and the configured content of the second address are exchanged. For details, see Table 13. No details are described herein. Table 13 Scenario Protected data First address Second address Third address (MLDnoAP 1, MLD no AP2) MAC address of MLD noAP 1 MAC address of MLD noAP2 MAC address of AP MLD S1502: The second device sends a first unit of data. The first data unit includes a first header, the first header is determined based on the protected data, and the first data unit is transmitted over a direct link between the first device and the second device. For example, the first data unit may be the MPDU shown in FIGURE 6, and the first header may be the MPDU header shown in FIGURE 6. Optionally, before or in a process in which the second device sends the first data unit in S1502, the first data unit may be determined. Specifically, one or more of the following Way 5 to Way 8 may be used. Way 5: The second device determines the first header of the first data unit. Optionally, the first header may include a fourth address, a fifth address, and a sixth address. For example, the first header may be the MPDU header shown in FIGURE 6. The fourth address may be addressl in the MPDU header, the fifth address may be address2 in the MPDU header, and the sixth address may be address3 in the MPDU header. In some embodiments, when the first device includes a STA, the fourth address is an address of the first device, the fifth address is an address of the second device, and the sixth address is an address of the first AP of the third device. Referring to FIGURE 8, when the first device includes a STA, and the second device is used as the TDLS initiator, the fourth address, the fifth address and the sixth address of the MPDU header are shown in Table 14. Due to that the initiator and the responder change, a difference between Table 14 and Table 8 in Way 1 above is that the configured content of the fourth address and the configured content of the fifth address are exchanged. For details, see Table 14. No details are described herein. iviA / a / zuzo / u i ut Table 14 Scenario First header Fourth address Fifth address Sixth address (legacy STA, noAP MLD 2) MAC address of legacy STA MAC address of MLD noAP 2 BSSID of AP 1 In some embodiments, when the first device includes a plurality of STAs, the fourth address is an address of a STA that corresponds to a first direct link and is located in the plurality of STAs of the first device, the fifth address is an address of a STA corresponding to the first direct link and located in a plurality of STAs of the second device, and the sixth address is an address of an AP corresponding to the first direct link and located in a plurality of APs of the third device. The first direct link is a direct link between the first device and the second device. Referring to FIGURE 9 and FIGURE 10, when the first device includes a plurality of STAs, and the second device is used as the TDLS initiator, the fourth address, the fifth address and the sixth address of the MPDU header are shown in Table 15. Because the initiator and the responder change, a difference between Table 15 and Table 9 in Way 1 above is that the configured content of the fourth address and the configured content of the fifth address are exchanged. For details, see Table 15. No details are described herein. It should be noted that, when there is a plurality of direct links between the first device and the second device, the first direct link may be a direct link for transmitting the first data unit on the direct links between the first device and the second device. Table 15 iviA / a / zuzo / u i ut fo Scenario First header Fourth address Fifth address Sixth address (MLD noAP 1, MLD noAP2) MAC address of STA 1 affiliate of MLD no AP 1 MAC address of STA 1 affiliate of MLD no AP2 BSSID of AP 1 affiliate of AP MLD Way 6: The second device determines a first element of the first data unit. In some embodiments, the first data unit may include a TDLS frame, and the TDLS frame includes the first element. The first element indicates an identifier of a target link or an address of an AP that corresponds to the target link and is located in the plurality of APs of the third device. For example, the first element can be set to a BSSID corresponding to the target link. Optionally, the target link is a second direct link to which the TDLS frame is applied, and the second direct link is a direct link between the first device and the second device. For specific implementations of Way 6, the TDLS frame and the first element, see Way 2 above. No details are described again herein. Way 7: The second device determines a second element of the first data unit. In some embodiments, the first data unit may include a TDLS frame, and the TDLS frame may include a trigger scheduling element and the second element. An offset field in the activation scheduling element is an offset with respect to a first timing synchronization function threshold of a third direct link, the second element may indicate an identifier of the third direct link or an address of an AP that corresponds to the third direct link and which are located in the plurality of APs of the third device, and the third direct link is a direct link between the first device and the second device. For a specific implementation, reference is made to the corresponding implementation in Way 3 above. No details are described again herein. It should be noted that, similar to Way 2 and Way 3, Way 6 and Way 7 can be used independently or in combination, and no details are described again herein. Table 16 TDLS Frame Transmission Mode Frame Type Note First Element Legacy STA and Non-AP2 MLD MLDnoAP 1 and Non-AP MLD 1 TDLS Discovery Request Frame Via AP Data Frame MLD Level Set to a BSSID corresponding to a reference link Set to a BSSID corresponding to a reference link Direct TDLS discovery response frame Management frame Allow unsolicited sending MLD level Set to a BSSID corresponding to a broadcast link to send the TDLS discovery request frame Set to a BSSID corresponding to a common link to transmit the TDLS discovery response frame (TDLS discovery response frame can be transmitted over any common link) TDLS configuration request frame Via AP Data frame MLD level Set to a BSSID of a link on which the legacy STA is located is set to a BSSID corresponding to a reference link, and a BSSID in the TDLS configuration request / response / confirm frame remains unchanged TDLS configuration response frame ViaAP Data Frame MLD Level Set to a BSSID of a link on which the legacy STA is located TDLS Configuration Confirmation Frame ViaAP Data Frame MLD Level Set to a BSSID of a link on which the legacy STA is located Inherited STA Both Frame MLD Level Frame; Set to Set to an address Allowed TDLS override of data and if a direct link is unreachable, forwarding is performed by an AP a BSSID of a link on which the legacy STA MAC of MLD AP is located or a BSSID of a direct link Switching request frame channel TDLS Direct Data frame Link level Set to a BSSID of a link on which the legacy STA is located Set to the BSSID corresponding to the target link Channel switch response frame TDLS Direct Data frame Link level Set to a BSSID of a link on which the legacy STA is located Set to the BSSID corresponding to the target link TDLS peer power saving management request frame Both allowed Data frame MLD level Set to a BSSID of a link on which the legacy STA is located finds the legacy STA Set to a BSSID of the third direct link corresponding to the activation scheduling element Peer Power Saving Management Response Frame TDLS Direct Data Frame MLD Level Set to a BSSID of a link on which the legacy STA is located Legacy STA Set to the BSSID of the third direct link corresponding to the activation scheduling element TDLS Peer Traffic Indication Frame Via AP Data Frame MLD Level Set to a BSSID of a link on which the legacy STA is located Set to the address of the third device, for example, an AP MAC address MLD Peer traffic response frame TDLS Direct Data frame MLD level Set to a BSSID of a link on which the legacy STA is located Set to the address of the third device device, for example, an AP MLD MAC address For different TDLS frames, the following describes a way of configuring the above link identifier element or a newly defined element with reference to Table 16 above. In other words, when the TDLS frames are different frames, the link identifier element, the newly defined element, the BSSID field in the link identifier element, or a first field of the newly defined element may correspond to different configured content. For ease of description, the link identifier element, the newly defined element, the first element, and the second element are referred to collectively as the first element below. A main difference between a way to configure the first item when the second device is used as the TDLS initiator and a way to configure the first item when the first device is used as the TDLS initiator is in a scenario where the first device includes a STA and the TDLS frame is a TDLS discovery request frame. For example, when the first device includes a STA, and the TDLS frame is a TDLS discovery request frame, the first element indicates an identifier of a reference link, or an address of an AP that corresponds to the reference link and that is located in the plurality of APs of the third device. The reference link may be a link indicated by the BSSID field in the link identifier element. For example, the first element can be set to the BSSID corresponding to the referral link. In another scenario shown in Table 16, for a specific implementation of the first element, reference is made to the corresponding first element implementation in Table 10 when the first device is used as a TDLS initiator. No details are described again herein. For specific implementations of the reference link, broadcast link and common link, reference is made to the corresponding implementations in Way 3 above. No details are described again herein. Way 8: The second device determines a third element of the first data unit. Optionally, the first data unit may include the third element, the third element may indicate configuring at least a fourth direct link on a first link, the first link is a common link of a link between the first device and the third device and a link between the second device and the third device, and the first link includes the at least a fourth direct link. For a specific implementation, reference is made to the corresponding implementation in Way 4 above. No details are described again herein. In a possible design solution, a direct link can be established between the first device and the second device on a non-common link. When the direct link is set to the non-common link, an implementation of the third element is similar to a specific implementation of the third element corresponding to a scenario in which a direct link is established on the common link. . For example, the third element may indicate configuring at least a fifth direct link on a second link. The second link is a link other than the link between the first device and the third device and the link between the second device and the third device, and the second link may include the at least a fifth direct link. In this way, the first device and the second device can establish a direct link on the non-common link, to increase a data transmission rate. For a specific implementation, reference is made to the corresponding implementation in Way 4 above. No details are described again herein. It should be noted that Way 5 through Way 8 above can be used in combination with the direct link addressing method shown in FIGURE 15, or Way 5 through Way 8 above can be used independently or in combination with each other. Yeah. This is not limited in this application. In some embodiments, a seventh address is linked to a TDLS TPK pair key. Optionally, the seventh address may include an address of an AP that corresponds to the direct link between the first device and the second device and that is located in the plurality of APs of the third device or addresses of all APs of the third device, and the address of the third device. For a specific implementation, reference is made to the implementation in which the first device binds the seventh address to the TPK. No details are described again herein. In a possible design solution, the direct link addressing method provided in this embodiment of this application may further include a TPK bypass process shown in the following step 3 and step 4. It should be noted that step 3 and Step 4 can be used independently, or can be used in combination with the method, Way 5, Way 6, Way 7 and / or Way 8 shown in FIGURE 15. Step 3: The first device negotiates with the second device to determine an AKM set selector. For specific implementation, please refer to step 1 above, and details are not described again herein. Step 4: The first device negotiates with the second device to derive the TDLS TPK pair key. For specific implementation, please refer to step 2 above, and details are not described again herein. It is noted that the above step 3 and step 4 can also be applied to the derivation of a pairwise master key (Pairwise Master Key, PTK), and the seventh address can be linked to the PTK. No details are described again herein. In some embodiments, the first device and the second device may complete the TPK bypass handshake negotiation by exchanging a TDLS configuration request / response / confirmation frame (for details, see next step d to step f). To be specific, the above step 3 and step 4 can be used in combination with the following step d to step f to complete the TPK bypass handshake negotiation. An example is used where the second device is used as a TDLS initiator. Step d to step f are similar to step a to step c above, and step d to step f correspond respectively to step a to step c above. A main difference is that the first device in step a to step c above is replaced with the second device, and the second device is replaced with the first device. No details are described again herein. According to the direct link addressing method described in FIGURE 15, when the first device includes a STA, the protected data is constructed by using the address of the first device, the address of the second device, and the address of the first AP connected to the first device. When the first device includes a plurality of STAs, the protected data is constructed by using the address of the first device, the address of the second device, and the address of the third device. Therefore, the first device can transmit the first unit of data through the direct link between the first device and the second device, without forwarding by the third device, thereby increasing a data transmission rate. Furthermore, when the first device includes a plurality of STAs, the protected data is constructed by using the addresses of the devices, and a change of the direct link does not affect the protected data. Therefore, when data is transmitted over a plurality of direct links, encryption does not need to be performed again, which further increases the data transmission speed. For example, FIGURE 16 is a schematic flowchart of another direct link addressing method according to an embodiment of the present application. An example where a first device is used as a TDLS initiator is used for description. The direct link addressing method is applicable to communication between the STA device and the non-AP MLD 2 shown in FIGURE 1 or between the non-AP MLD 1 and the non-AP MLD 2 shown in FIGURE 1. S1601: The first device determines a first data unit. The first data unit includes a first header, and the first header includes a fourth address, a fifth address, and a sixth address. In some embodiments, the first data unit may include a frame body. For example, the frame body may be a TDLS frame or data. For example, the first data unit may be the MPDU shown in FIGURE 6, the first header may be the MPDU header shown in FIGURE 6, and the TDLS frame iviA / a / zuzo / u i ut or the data is carried in the frame body field. In some embodiments, when the first device includes a STA, the fourth address is an address of a second device, the fifth address is an address of the first device, the sixth address is an address of a first AP of a third device, and the first device connects to the first AP of the third device. With reference to the FIGURES, the firstAP is AP 1 in the FIGURES. When the first device includes a STA and the first device is used as a TDLS initiator, the fourth address, fifth address, and sixth address of the MPDU header are shown in Table 17. The fourth address is a non-AP MLD address 2, for example, a MAC address of the non-AP MLD 2. The fifth address is an address of a legacy STA, for example, a MAC address of the legacy STA. The sixth address is an address of AP 1, for example, a BSSID of AP 1. iviA / a / zuzo / u i ut Table 17 Scenario First header Fourth address Fifth address Sixth address (legacy STA, MLD noAP 2) MAC address of MLD noAP2 MAC address of legacy STA BSSID of AP 1 In some embodiments, when the first device includes a plurality of STAs, the fourth address is an address of the second device, the fifth address is an address of the first device, and the sixth address is an address of an AP that corresponds to a sixth direct link. and which is located in a plurality of APs of the third device, where the sixth direct link is a link for transmitting the first unit of data between the first device and the second device. The first unit of data is transmitted over a direct link between the first device and the second device. For example, FIGURE 9 and FIGURE 10 show an example in which the first device is the MLD non-AP 1, the second device is the MLD non-AP 2, and the third device is the AP MLD. When the first device includes a plurality of STAs, and the first device is used as the TDLS initiator, the fourth address, the fifth address and the sixth address of the MPDU header are shown in Table 18. It is assumed that the first device data is transmitted over a direct link 1, the fourth address is an address of a STA 1 of the non-AP MLD 2, for example, a MAC address of the non-AP MLD 2; the fifth address is an address of a STA 1 of the non-AP MLD 1, for example, a MAC address of the non-AP MLD 1; and the sixth address is an address of an AP 1 corresponding to direct link 1, for example, a BSSID of AP1 affiliated with the MLD of the AP. Table 18 Scenario First header Fourth address Fifth address Sixth address (legacy STA, noAP MLD 2) MAC address of noAP MLD 2 MAC address of noAP MLD 1 BSSID of AP 1 iviA / a / zuzo / u i ut Specifically, the ways of configuring the sixth address corresponding to Table 17 and Table 18 may be the same in both a case where the first device includes a STA and a case where the first device includes a plurality of STAs , to avoid frequent modification of the configured content of the sixth address, thereby reducing a transmission delay. Optionally, the TDLS frame may be a TDLS discovery response frame. Table 17 and Table 18 may be ways of configuring addresses of a first header of a management frame. Because the TDLS discovery response frame is encapsulated in a common management frame and does not need to be encrypted, the corresponding AAD construct may not be determined. S1602: The first device sends the first unit of data. Correspondingly, the second device receives the first data unit from the first device. According to the direct link addressing method described in FIGURE 16, when the first device includes a STA, the first header is constructed by using the address of the first device, the address of the second device, and the address of the first AP connected to the first device. When the first device includes a plurality of STAs, the first header when constructed by using the address of the first device, the address of the second device and the address of the AP that corresponds to the sixth direct link and is located in the plurality of APs of the third device, where the sixth direct link is a link for transmitting the first data unit between the first device and the second device. Therefore, the first device can transmit the first unit of data through the direct link between the first device and the second device, without forwarding by the third device, thereby increasing a data transmission rate. Furthermore, a way of configuring the sixth address may be the same in both a case where the first device includes a STA and a case where the first device includes a plurality of STAs, to avoid frequent modification of the configured content. of the sixth address, thus further reducing a transmission delay. For example, FIGURE 17 is a schematic flowchart of another direct link addressing method according to an embodiment of the present application. An example where a second device is used as a TDLS initiator is used for description. The direct link addressing method is applicable to communication between the STA device and the non-AP MLD 2 shown in FIGURE 1 or between the non-AP MLD 1 and the non-AP MLD 2 shown in FIGURE 1. S1701: The second device determines a first data unit. The first data unit includes a first header, and the first header includes a fourth address, a fifth address, and a sixth address. In some embodiments, the first data unit may include a frame body. For example, the frame body may be a TDLS frame or data. For example, the first data unit may be the MPDU shown in FIGURE 6, the first header may be the MPDU header shown in FIGURE 6, and the TDLS frame or data is carried in a frame body field. In some embodiments, when a first device includes a STA, the fourth address is an address of the first device, the fifth address is an address of the second device, the sixth address is an address of a first AP of a third device and the first device connects to the first AP of the third device. Referring to FIGURE 8, when the first device includes a STA, and the second device is used as the TDLS initiator, the fourth address, the fifth address and the sixth address of the MPDU header are shown in Table 19. Due to that the initiator and a responder exchange, a difference between Table 19 and Table 17 in S1601 is that the configured content of the fourth address and the configured content of the fifth address are exchanged. For details, see Table 19. No details are described herein. Table 19 iviA / a / zuzo / ui ut Scenario First header Fourth address Fifth address Sixth address (legacy STA, noAP2 MLD) Legacy STA MAC address noAP2 MLD MAC address BSSID of an AP 1 In some embodiments, when the first device includes a plurality of STAs, the fourth address is an address of the first device, the fifth address is an address of the second device, and the sixth address is an address of an AP that corresponds to a sixth direct link. and which is located in a plurality of APs of a third device, where the sixth direct link is a link for transmitting the first data unit between the first device and the second device. The first unit of data is transmitted over a direct link between the first device and the second device. Referring to FIGURE 9 and FIGURE 10, when the first device includes a plurality of STAs, and the second device is used as the TDLS initiator, the fourth address, the fifth address and the sixth address of the MPDU header are shown in Table 20. Because the initiator and a responder change, a difference between Table 20 and Table 18 in S1601 is that the configured content of the fourth address and the configured content of the fifth address are exchanged. For details, see Table 20. No details are described herein. iviA / a / zuzo / u i ut fo Table 20 Scenario First header Fourth address Fifth address Sixth address (MLD noAP 1, MLD no AP2) MAC address of STA 1 affiliate of MLD no AP 1 MAC address of STA 1 affiliate of MLD no AP2 BSSID of AP1 affiliate of AP MLD Optionally, the TDLS frame may be a TDLS discovery response frame. S1702: The second device sends the first unit of data. Correspondingly, the first device receives the first data unit from the second device. It should be noted that for a technical effect of the method shown in FIGURE 17, reference is made to a technical effect of the method shown in FIGURE 16. No details are described again herein. It should be noted that an address configuration rule of the first data unit (for example, an MPDU) and the protected data construction (for example, an AAD) provided in this embodiment of this application is applicable to a frame of a diffusion. The following describes several special application scenarios to which embodiments of this application are applicable. It should be understood that the application scenarios of the modalities of this application are not limited to the following application scenarios. Scenario 1 It is assumed that the AP MLD corresponds to three links: a link 1, a link 2 and a link 3. Two links, link 1 and link 2, are established between the non-AP MLD 1 and the MLD AP, and link 1 and link 3 are established between the non-AP MLD 2 and the MLD AP. In this case, non-AP MLD 1 and non-AP MLD 2 can configure multilink TDLS. Link 1 is known as a common link, and the other link is known as a non-common link. A link identifier corresponding to link 1 may be indicated by a link ID or a BSSID of an AP associated with either end of the link. For data transmission on the non-common link, two ends of the non-common link can negotiate, through the common link, on which channel data is transmitted. For example, when the non-common link is switched to a channel on which one end is located for transmission, a peer end is equivalent to off-channel (off-channel) transmission, and the peer end needs to notify the AP that the end pair enters a doze state, and then switches to a channel on which the other end is located for direct transmission. In the above scenario, there is at least a common link need to establish a direct link between non-AP MLDs. Otherwise, a TDLS discovery response frame is not allowed to be responded to or TDLS configuration is started. When a plurality of common links exist between non-AP MLDs, the TDLS discovery response frame can be responded over any common link. However, when a link corresponding to the BSSID field in the link identifier element is also a common link, the TDLS discovery response frame may be responded preferentially over the common link. In addition, non-AP MLDs at both ends can use different addressing modes, such as transparent broadcast mode and non-transparent broadcast mode. Scenario 2 The AP MLD is assumed to correspond to three links: a link 1, a link 2 and a link 3. Two links, link 1 and link 2, are established between the non-AP MLD 1 and the AP MLD, and the STA inherited is associated with link 2. If the non-AP MLD, as initiator, sends a TDLS discovery request frame, and a BSSID in a link identifier element carried in the TDLS discovery request frame is set to a BSSID corresponding to link 1, after receiving the TDLS discovery request frame, when the inherited STA finds that the BSSID in the link identifier element is inconsistent with a BSSID in which the inherited STA is located, the inherited STA does not return a TDLS discovery response frame on link 2, resulting in a discovery failure. This situation occurs because the non-AP MLD does not know whether an endpoint peers a legacy STA or a non-AP MLD, and does not know which AP the peer endpoint is associated with. To avoid this situation, the non-AP MLD may forward a TDLS discovery request frame, and a BSSID in a link identifier element carried in the TDLS discovery request frame is set to a BSSID corresponding to link 2. In this way , after receiving the TDLS discovery request frame, when the legacy STA finds that the BSSID in the link identifier element is consistent with the BSSID in which the legacy STA is located, the legacy STA returns a response frame TDLS discovery on link 2, so that the discovery is successful. Scenario 3 iviA / a / zuzo / u i ut The AP MLD is assumed to correspond to three links: a link 1, a link 2 and a link 3. Two links, link 1 and link 2, are established between the non-AP MLD 1 and the AP MLD, and the legacy STA is associated with link 2. If the legacy STA, as the initiator, sends a TDLS discovery request frame on link 2, after receiving the TDLS discovery request frame, the non-AP MLD can return a TDLS discovery response frame over only one link (i.e. link 2) indicated by a BSSID in a link identifier element. When both the TDLS initiator and the TDLS responder are MLD, the TDLS discovery request frame and the TDLS discovery response frame each carry a multilink element. This way, both ends know that a peer end is also an MLD device through a TDLS discovery process. Additionally, through the TDLS discovery process, the TDLS initiator and TDLS responder can know which links are common links. The direct link addressing method provided in embodiments of this application is described above in detail with reference to FIGURE 7 to FIGURE 17. The following describes in detail a direct link addressing apparatus provided in embodiments of this application with reference to FIGURE 18 and FIGURE 19. FIGURE 18 is a schematic diagram of a structure of a direct link addressing apparatus that can be configured to implement the direct link addressing method provided in embodiments of this application. A direct link addressing apparatus 1800 may be a first device or a second device, or may be a chip applied to a first device or a second device or other component that has a corresponding function. As shown in FIGURE 18, the direct link addressing apparatus 1800 may include a processor 1801 and a transceiver 1803. The direct link addressing apparatus 1800 may further include a memory 1802. The processor 1801 is coupled to the memory 1802. and transceiver 1803. For example, processor 1801 may be connected to memory 1802 and transceiver 1803 via a communication bus. The 1801 processor can alternatively be used independently. The following describes each component of the direct link addressing apparatus 1800 in detail with reference to FIGURE 18. The processor 1801 is a control center of the direct link addressing apparatus 1800; and may be a processor, or may be a collective term for a plurality of processing elements. For example, processor 1801 is one or more central processing units (CPU), or may be an application-specific integrated circuit (ASIC), or is configured as one or more integrated circuits. to implement modalities of this application, for example, one or more microprocessors (digital signal processor, DSP) or one or more field programmable gate arrays (FPGA). The processor 1801 may execute various functions of the direct link addressing apparatus 1800 by running or executing a software program stored in the memory 1802 and calling data stored in the memory 1802. During the specific implementation, in one embodiment, the processor 1801 may include one or more CPUs, such as a CPU 0 and a CPU 1 shown in FIGURE 18. During the specific implementation, in one embodiment, the direct link addressing apparatus 1800 may alternatively include a plurality of processors, for example, the processor 1801 and a processor 1804 shown in FIGURE 18. Each of the processors may be a single core processor (single CPU) or it can be a multi-core processor (multiple CPU). The processor herein may be one or more communication devices, circuits and / or processing cores configured to process data (e.g., computer program instructions). The memory 1802 may be a read-only memory (ROM) or other type of static storage communication device that can store static information and instructions, a random access memory (RAM) or other type of dynamic storage communication device that can store information and instructions, an electrically erasable programmable read-only memory (EEPROM), a compact disc read-only memory , CD-ROM) or other compact disc storage, an optical disc storage (including a compact disc, a laser disc, an optical disc, a digital versatile disc, a Blu-ray disc, or the like), a media magnetic disk storage or other magnetic storage communication device, or any other medium that can be used to carry or store expected program code in a form of an instruction or a data structure and that can be accessed by a computer . However, the memory 1802 is not limited thereto. Memory 1802 can be integrated with processor 1801; or it may exist independently, and is coupled to the processor 1801 through an input / output port (not shown in FIGURE 18) of the direct link addressing apparatus 1800. This is not specifically limited in this embodiment of this application. Memory 1802 is configured to store a software program to execute the solutions of this request, and processor 1801 controls the execution. For the above specific implementation, reference is made to the following method modalities. No details are described again herein. The transceiver 1803 is configured to communicate with another direct link iviA / a / zuzo / ui ut addressing device. For example, when the direct link addressing apparatus 1800 is the first device, the transceiver 1803 can be configured to communicate with the second device and a third device. For another example, when the direct link addressing apparatus 1800 is the second device, the transceiver 1803 can be configured to communicate with the first device and the third device. Additionally, transceiver 1803 may include a receiver and a transmitter (not shown separately in FIGURE 18). The receiver is configured to implement a receive function, and the transmitter is configured to implement a send function. Transceiver 1803 can be integrated with processor 1801; or it may exist independently, and is coupled to the processor 1801 through the input / output port (not shown in FIGURE 18) of the direct link addressing apparatus 1800. This is not specifically limited in this embodiment of this application. It should be noted that a structure of the direct link addressing apparatus 1800 shown in FIGURE 18 does not constitute a limitation on the direct link addressing apparatus. An actual direct link addressing apparatus may include more or fewer components than those shown in the figure, or combine some components, or have different component arrangements. The actions of the first device in the previous steps S701 and S702 and S1601 and S1602 can be performed by the processor 1801 in the direct link addressing apparatus 1800 shown in FIGURE 18 by invoking the application program code stored in the memory 1802 to indicate a remote terminal device to perform. The actions of the second device in the previous steps S1501 and S1502 and S1701 and S1702 can be performed by the processor 1801 in the direct link addressing apparatus 1800 shown in FIGURE 18 by invoking the application program code stored in the memory 1802 to indicate the remote terminal device to be carried out. This is not limited in this modality. FIGURE 19 is a schematic diagram of a structure of another direct link addressing apparatus according to an embodiment of this application. For ease of description, FIGURE 19 shows only the major components of the direct link addressing apparatus. A direct link addressing apparatus 1900 includes a transceiver module 1901. Optionally, the direct link addressing apparatus 1900 may further include a processing module 1902. The direct link addressing apparatus 1900 may be the first device or the second device in the above method modalities. The transceiver module 1901 may also be referred to as a transceiver unit, and is configured to implement a transceiver function performed by the first iviA / a / zuzo / ui ut device or the second device in any of the above method embodiments. It should be noted that the transceiver module 1901 may include a receive module and a send module (not shown in FIGURE 19). The receiving module is configured to implement a receiving function performed by the first device or the second device in any of the above method embodiments. The dispatch module is configured to implement a dispatch function performed by the first device or the second device in any of the above method embodiments. A specific implementation of the transceiver module 1901 is not specifically limited in the present application. The processing module 1902 may also be referred to as a processing unit and may be configured to implement a processing function performed by the first device or the second device in any of the above method embodiments. The processing module 1902 may be a processor. In this embodiment, the direct link addressing apparatus 1900 is presented in a way of dividing each functional module in an integrated manner. The module herein may be a specific ASIC, a circuit, a processor running one or more software or firmware programs, a memory, an integrated logic circuit and / or other component capable of providing the above functions. In a simple embodiment, one skilled in the art may discover that the direct link addressing apparatus 1900 can be found in a form of the direct link addressing apparatus 1800 shown in FIGURE 18. For example, the processor 1801 in the direct link addressing apparatus 1800 shown in FIGURE 18 may invoke computer executable instructions stored in the memory 1802, so that the direct link addressing apparatus 1800 performs the link addressing method. directly in the above method modalities. Specifically, a function / implementation process of the transceiver module 1901 and the processing module 1902 in FIGURE 19 can be implemented by the processor 1801 in the direct link addressing apparatus 1800 shown in FIGURE 18 by invoking the stored computer executable instructions in memory 1802. Alternatively, a function / implementation process of the processing module 1902 in FIGURE 19 may be implemented by the processor 1801 in the direct link addressing apparatus 1800 shown in FIGURE 18 by invoking the stored computer executable instructions in the memory 1802, and a function / implementation process of the transceiver module 1901 in FIGURE 19 can be implemented by the transceiver 1803 in the direct link addressing apparatus 1800 shown in FIGURE 18. iviA / a / zuzo / u i ut Because the direct link addressing apparatus 1900 provided in this embodiment can execute the above direct link addressing method, for the technical purposes that can be achieved by the direct link addressing apparatus 1900, reference is made to the embodiments of previous methods. No details are described again herein. In a possible design solution, the direct link addressing apparatus 1900 shown in FIGURE 19 is applicable to the communication system shown in FIGURE 1, and performs a function of the first device in the direct link addressing method shown in the FIGURE 7. The direct link addressing apparatus 1900 includes one or more STA stations. The direct link addressing apparatus 1900 connects to a third device, and the third device includes a plurality of access points APs. The second device connects to the third device, and the second device includes a plurality of STAs. The processing module 1902 is configured to determine the protected data. The protected data includes a first address, a second address and a third address. When the direct link addressing apparatus 1900 includes a STA, the first address is an address of the second device, the second address is an address of the direct link addressing apparatus 1900, the third address is an address of a first AP of the third device and the direct link addressing apparatus 1900 connects to the first AP of the third device. When the direct link addressing apparatus 1900 includes a plurality of STAs, the first address is an address of the second device, the second address is an address of the direct link addressing apparatus 1900, and the third address is an address of the third device. The transceiver module 1901 is configured to send a first unit of data. The first data unit includes a first header, the first header is determined based on the protected data, and the first data unit is transmitted over a direct link between the direct link addressing apparatus 1900 and the second device. Optionally, the direct link addressing apparatus 1900 may further include a storage module (not shown in FIGURE 19), and the storage module stores programs or instructions. When the processing module 1902 executes the programs or instructions, the direct link addressing apparatus 1900 can perform the function of the first device in the direct link addressing method shown in FIGURE 7. It should be noted that the direct link addressing apparatus 1900 may be the first device, or it may be a chip (system) or other component or assembly that may be provided in the first device. This is not limited in this application. Furthermore, for a technical effect of the direct link addressing apparatus 1900, reference is made to a technical effect of the direct link addressing method shown in FIGURE 7. No details are described again herein. In another possible design solution, the direct link addressing apparatus 1900 shown in FIGURE 19 is applicable to the communication system shown in FIGURE 1, and performs a function of the second device in the direct link addressing method shown in FIGURE 7. The direct link addressing apparatus 1900 includes a plurality of STA stations. The forward link addressing apparatus 1900 connects to a third device, and the third device includes a plurality of access points APs. The first device connects to the third device, and the first device includes one or more STAs. The transceiver module 1901 is configured to receive a first unit of data. The first data unit includes a first header, the first header is determined based on protected data, and the first data unit is transmitted over a direct link between the first device and the direct link addressing apparatus 1900. Protected data includes a first address, a second address and a third address. When the first device includes a STA, the first address is an address of the direct link addressing apparatus 1900, the second address is an address of the first device, the third address is an address of a first AP of the third device and the first device connects to the first AP of the third device. When the first device includes a plurality of STAs, the first address is an address of the direct link addressing apparatus 1900, the second address is an address of the first device, and the third address is an address of the third device. Optionally, the direct link addressing apparatus 1900 may further include the processing module 1902 and a storage module (not shown in FIGURE 19), and the storage module stores programs or instructions. When the processing module 1902 executes the programs or instructions, the direct link addressing apparatus 1900 can perform the function of the second device in the direct link addressing method shown in FIGURE 7. It should be noted that the direct link addressing apparatus 1900 may be the second device, or it may be a chip (system) or other component or assembly that may be provided in the second device. This is not limited in this application. Furthermore, for a technical effect of the direct link addressing apparatus 1900, reference is made to a technical effect of the direct link addressing method shown in FIGURE 7. No details are described again herein. iviA / a / zuzo / u i ut fo In yet another possible design solution, the direct link addressing apparatus 1900 shown in FIGURE 19 is applicable to the communication system shown in FIGURE 1, and performs a function of the second device in the direct link addressing method. shown in FIGURE 15. The direct link addressing apparatus 1900 includes a plurality of STA stations, the direct link addressing apparatus 1900 connects to a third device, the third device includes a plurality of access points APs, the first device connects to the third device and the first device includes one or more STAs. The processing module 1902 is configured to determine the protected data. The protected data includes a first address, a second address and a third address. When the first device includes a STA, the first address is an address of the first device, the second address is an address of the direct link addressing apparatus 1900, the third address is an address of a first AP of the third device and the first device connects to the first AP of the third device. When the first device includes a plurality of STAs, the first address is an address of the first device, the second address is an address of the direct link addressing apparatus 1900, and the third address is an address of the third device. The transceiver module 1901 is configured to send a first unit of data. The first data unit includes a first header, the first header is determined based on the protected data, and the first data unit is transmitted over a direct link between the first device and the direct link addressing apparatus 1900. Optionally, the direct link addressing apparatus 1900 may further include a storage module (not shown in FIGURE 19), and the storage module stores programs or instructions. When the processing module 1902 executes the programs or instructions, the direct link addressing apparatus 1900 may perform a function of the second device in the direct link addressing method shown in FIGURE 15. It should be noted that the direct link addressing apparatus 1900 may be the second device, or it may be a chip (system) or other component or assembly that may be provided in the second device. This is not limited in this application. Furthermore, for a technical effect of the direct link addressing apparatus 1900, reference is made to a technical effect of the direct link addressing method shown in FIGURE 15. No details are described again herein. In yet another possible design solution, the direct link addressing apparatus 1900 shown in FIGURE 19 is applicable to the communication system shown in FIGURE 1, and performs a function of the first device in the iviA / addressing method. a / zuzo / u i ut direct link shown in FIGURE 15. The direct link addressing apparatus 1900 includes one or more STA stations. The direct link addressing apparatus 1900 is connected to a third device, the third device includes a plurality of access points APs, the second device connects to the third device, and the second device includes a plurality of STAs. The transceiver module 1901 is configured to receive a first unit of data. The first data unit includes a first header, the first header is determined based on the protected data, and the first data unit is transmitted over a direct link between the direct link addressing apparatus 1900 and the second device. The protected data includes a first address, a second address and a third address. When the direct link addressing apparatus 1900 includes a STA, the first address is an address of the direct link addressing apparatus 1900, the second address is an address of the second device, and the third address is an address of a first AP of the third device, the direct link addressing apparatus 1900 connects to the first AP of the third device and the direct link addressing apparatus 1900 includes a STA. When the direct link addressing apparatus 1900 includes a plurality of STAs, the first address is an address of the direct link addressing apparatus 1900, the second address is an address of the second device, and the third address is an address of the third device. Optionally, the direct link addressing apparatus 1900 may further include a processing module 1902 and a storage module (not shown in FIGURE 19), and the storage module stores programs or instructions. When the processing module 1902 executes the programs or instructions, the direct link addressing apparatus 1900 may perform a function of the first device in the direct link addressing method shown in FIGURE 15. It should be noted that the direct link addressing apparatus 1900 may be the first device, or it may be a chip (system) or other component or assembly that may be provided in the first device. This is not limited in this application. Furthermore, for a technical effect of the direct link addressing apparatus 1900, reference is made to a technical effect of the direct link addressing method shown in FIGURE 15. No details are described again herein. In yet another possible design solution, the direct link addressing apparatus 1900 shown in FIGURE 19 is applicable to the communication system shown in FIGURE 1, and performs a function of the first device in the direct link addressing method. shown in FIGURE 16. The direct link addressing apparatus 1900 includes one or more STA stations. The direct link addressing apparatus 1900 iviA / a / zuzo / u i ut connects to a third device, the third device includes a plurality of access points APs, the second device connects to the third device, and the second device includes a plurality of STA. The processing module 1902 is configured to determine the first data unit. The first data unit includes a first header and a tunneled forward link configuration TDLS frame, and the first header includes a fourth address, a fifth address, and a sixth address. When the direct link addressing apparatus 1900 includes a STA, the fourth address is an address of the second device, the fifth address is an address of the direct link addressing apparatus 1900, the sixth address is an address of the first AP of the third device and the direct link addressing apparatus 1900 connects to the first AP of the third device. When the direct link addressing apparatus 1900 includes a plurality of STAs, the fourth address is an address of the second device, the fifth address is an address of the direct link addressing apparatus 1900, the sixth address is an address of an AP that corresponds to a sixth direct link and is located in the plurality of APs of the third device, and the sixth direct link is a link for transmitting the TDLS frame between the direct link addressing apparatus 1900 and the second device. The transceiver module 1901 is configured to send a first unit of data. The first data unit is transmitted over a direct link between the direct link addressing apparatus 1900 and the second device. Optionally, the TDLS frame may be a TDLS discovery response frame. Optionally, the direct link addressing apparatus 1900 may further include a storage module (not shown in FIGURE 19), and the storage module stores programs or instructions. When the processing module 1902 executes the programs or instructions, the direct link addressing apparatus 1900 may perform a function of the first device in the direct link addressing method shown in FIGURE 16. It should be noted that the direct link addressing apparatus 1900 may be the first device, or it may be a chip (system) or other component or assembly that may be provided in the first device. This is not limited in this application. Furthermore, for a technical effect of the direct link addressing apparatus 1900, reference is made to a technical effect of the direct link addressing method shown in FIGURE 16. No details are described again herein. In yet another possible design solution, the direct link addressing apparatus 1900 shown in FIGURE 19 is applicable to the communication system shown in the iviA / a / zuzo / u i ut fo FIGURE 1, and perform a function of the second device in the direct link addressing method shown in FIGURE 16. The direct link addressing apparatus 1900 includes a plurality of STA stations. The forward link addressing apparatus 1900 connects to a third device, and the third device includes a plurality of access points APs. The first device connects to the third device, and the first device includes one or more STAs. The transceiver module 1901 is configured to receive a first unit of data. The first data unit includes a first header and a tunneled forward link configuration TDLS frame, and the first header includes a fourth address, a fifth address, and a sixth address. When the first device includes a STA, the fourth address is an address of the direct link addressing apparatus 1900, the fifth address is an address of the first device, the sixth address is an address of a first AP of the third device and the first device connects to the first AP of the third device. When the first device includes a plurality of STAs, the fourth address is an address of the direct link addressing apparatus 1900, the fifth address is an address of the first device, the sixth address is an address of an AP corresponding to a sixth link direct and located in the plurality of APs of the third device, and the sixth direct link is a link for transmitting the TDLS frame between the first device and the direct link addressing apparatus 1900. The first data unit is transmitted through a direct link between the first device and the direct link addressing apparatus 1900. Optionally, the TDLS frame may be a TDLS discovery response frame. Optionally, the direct link addressing apparatus 1900 may further include the processing module 1902 and a storage module (not shown in FIGURE 19), and the storage module stores programs or instructions. When the processing module 1902 executes the programs or instructions, the direct link addressing apparatus 1900 can perform the function of the second device in the direct link addressing method shown in FIGURE 16. It should be noted that the direct link addressing apparatus 1900 may be the second device, or it may be a chip (system) or other component or assembly that may be provided in the second device. This is not limited in this application. Furthermore, for a technical effect of the direct link addressing apparatus 1900, reference is made to a technical effect of the direct link addressing method shown in FIGURE 16. No details are described again herein. iviA / a / zuzo / u i ut fo In yet another possible design solution, the direct link addressing apparatus 1900 shown in FIGURE 19 is applicable to the communication system shown in FIGURE 1, and performs a function of the second device in the direct link addressing method. shown in FIGURE 17. The direct link addressing apparatus 1900 includes a plurality of STA stations. The forward link addressing apparatus 1900 connects to a third device, and the third device includes a plurality of access points APs. The first device connects to the third device, and the first device includes one or more STAs. The processing module 1902 is configured to determine a first data unit. The first data unit includes a first header and a tunneled forward link configuration TDLS frame, and the first header includes a fourth address, a fifth address, and a sixth address. The transceiver module 1901 is configured to send the first unit of data. When the first device includes a STA, the fourth address is an address of the first device, the fifth address is an address of the direct link addressing apparatus 1900, the sixth address is an address of a first AP of the third device and the first device connects to the first AP of the third device. When the first device includes a plurality of STAs, the fourth address is an address of the first device, the fifth address is an address of the direct link addressing apparatus 1900, and the sixth address is an address of an AP corresponding to a sixth link direct and which is located in the plurality of APs of the third device. The sixth direct link is a link for transmitting the TDLS frame between the first device and the direct link addressing apparatus 1900. The first data unit is transmitted over a direct link between the first device and the direct link addressing apparatus 1900. direct 1900. Optionally, the TDLS frame may be a TDLS discovery response frame. Optionally, the direct link addressing apparatus 1900 may further include the processing module 1902 and a storage module (not shown in FIGURE 19), and the storage module stores programs or instructions. When the processing module 1902 executes the programs or instructions, the direct link addressing apparatus 1900 can perform the function of the second device in the direct link addressing method shown in FIGURE 17. It should be noted that the direct link addressing apparatus 1900 may be the second device, or it may be a chip (system) or other component or assembly that may be provided in the second device. This is not limited in this application. Furthermore, for a technical effect of the direct link addressing apparatus 1900, iviA / a / zuzo / u i ut reference is made to a technical effect of the direct link addressing method shown in FIGURE 17. No details are described again. at the moment. In yet another possible design solution, the direct link addressing apparatus 1900 shown in FIGURE 19 is applicable to the communication system shown in FIGURE 1, and performs a function of the first device in the direct link addressing method. shown in FIGURE 17. The direct link addressing apparatus 1900 includes one or more STA stations. The forward link addressing apparatus 1900 connects to a third device, and the third device includes a plurality of access points APs. The second device connects to the third device, and the second device includes a plurality of STAs. The transceiver module 1901 is configured to receive a first unit of data. The first data unit includes a first header and a tunneled forward link configuration TDLS frame, and the first header includes a fourth address, a fifth address, and a sixth address. When the direct link addressing apparatus 1900 includes a STA, the fourth address is an address of the direct link addressing apparatus 1900, the fifth address is an address of the second device, the sixth address is an address of a first AP of the third device and the direct link addressing apparatus 1900 connects to the first AP of the third device. When the direct link addressing apparatus 1900 includes a plurality of STAs, the fourth address is an address of the direct link addressing apparatus 1900, the fifth address is an address of the second device, and the sixth address is an address of an AP that corresponds to a sixth direct link and is located in the plurality of APs of the third device. The sixth direct link is a link for transmitting the TDLS frame between the direct link addressing apparatus 1900 and the second device. The first data unit is transmitted over a direct link between the direct link addressing apparatus 1900 and the second device. Optionally, the TDLS frame may be a TDLS discovery response frame. Optionally, the direct link addressing apparatus 1900 may further include the processing module 1902 and a storage module (not shown in FIGURE 19), and the storage module stores programs or instructions. When the processing module 1902 executes the programs or instructions, the direct link addressing apparatus 1900 can perform the function of the first device in the direct link addressing method shown in FIGURE 17. It should be noted that the direct link addressing apparatus 1900 may be the first device, or may be a chip (system) or other component or assembly that may be provided in the first device. This is not limited in this application. Furthermore, for a technical effect of the direct link addressing apparatus 1900, reference is made to a technical effect of the direct link addressing method shown in FIGURE 17. No details are described again herein. One embodiment of this application provides a communication system. The communication system includes a first device and a second device. The communication system may also include a third device. The first device is configured to perform actions of the first device in the above method embodiments. For a specific method and execution process, reference is made to the above method modalities. No details are described again herein. The second device is configured to perform actions of the second device in the above method embodiments. For a specific method and execution process, reference is made to the above method modalities. No details are described again herein. The third device is configured to perform actions of the third device in the above method embodiments. For a specific method and execution process, reference is made to the above method modalities. No details are described again herein. One embodiment of this application provides a chip system. The system chip includes a processor and an input / output port. The processor is configured to implement a processing function in the direct link addressing method provided in embodiments of this application. The input / output port is configured to implement a transceiver function in the direct link addressing method provided in embodiments of this application. In one possible design, the chip system also includes memory. The memory is configured to store program instructions and data to implement a function in the direct link addressing method provided in embodiments of this application. The chip system may include a chip, or may include a chip and another discrete component. One embodiment of this application provides a computer readable storage medium. Computer-readable storage medium includes computer programs or instructions. When computer programs or instructions are executed on a computer, the computer is activated to perform the direct link addressing method provided in the embodiments of this application. One embodiment of this application provides a computer program product. iviA / a / zuzo / ui ut The computer program product includes computer programs or instructions. When computer programs or instructions are executed on a computer, the computer is activated to perform the direct link addressing method provided in the embodiments of this application. It should be understood that the processor in the embodiments of the present application may be a central processing unit (CPU), or it may be another general purpose processor, a digital signal processor (DSP). , an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic device, hardware components discreet or similar. The general purpose processor may be a microprocessor or the processor may be any conventional processor or the like. It is further to be understood that the memory in the embodiments of this application may be volatile memory or non-volatile memory, or may include volatile memory and non-volatile memory. Non-volatile memory can be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an read-only electrically erasable programmable (electrically EPROM, EEPROM) or flash memory. Volatile memory can be random access memory (RAM), used as an external cache memory. By way of example rather than a limiting description, random access memory (RAM) can be used in many forms, for example, a static random access memory (SRAM), a dynamic random access memory (DRAM), a synchronous DRAM (SDRAM), a double data rate synchronous dynamic random access memory (DDR SDRAM), a enhanced SDRAM, ESDRAM, a synchlink dynamic random access memory (synchlink DRAM, SLDRAM), and a direct rambus random access memory (DR RAM). All or some of the above embodiments can be implemented using software, hardware (e.g., circuitry), firmware, or any combination thereof. When software is used to implement modalities, the above modalities may be implemented in whole or in part in a form of a computer program product. The computer program product includes one or more computer instructions or computer programs. When program instructions or computer programs are loaded and executed on a computer, iviA / a / zuzo / u i ut procedures or functions in accordance with modalities of this application are generated in whole or in part. The computer may be a general purpose computer, a special purpose computer, a network of computers, or other programmable devices. Computer instructions may be stored on a computer-readable storage medium or may be transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, computer instructions may be transmitted from one website, computer, server, or data center to another website, computer, server, or data center in a wired manner (e.g., infrared light, radio, or microwave). The computer-readable storage medium may be any usable medium accessible by a computer, or a data storage device, such as a server or a data center, that integrates one or more usable media. The usable medium may be a magnetic medium (for example, a floppy disk, a hard disk or a magnetic tape), an optical medium (for example, a DVD) or a semiconductor medium. The semiconductor medium may be a solid state unit. It should be understood that the term and / or in this specification describes only one association relationship between associated objects and indicates that there may be three relationships. For example, A and / or B can indicate the following three cases: Only A exists, both A and B exist, and only B exists. A and B can be singular or plural. Additionally, the / character in this specification generally indicates an or relationship between associated objects, or may indicate an and / or relationship. A specific meaning depends on the context. In this application, at least one means one or more, and a plurality of means two or more. At least one of the following elements (pieces) or a similar expression thereof refers to any combination of these elements, including any combination of singular elements (pieces) or plural elements (pieces). For example, at least one of a, b or c can indicate: a, b, c, a-b, a-c, b-c or a-b-c, where a, b and c can be singular or plural. It should be understood that the sequence numbers of the above processes do not mean execution sequences in various embodiments of this application. The execution sequences of the processes should be determined based on the functions and internal logic of the processes, and should not be construed as any limitations on the processes of implementing the modalities of this application. A person skilled in the art may be aware that, in combination with the examples described in embodiments disclosed in this specification, the algorithm units and steps may be implemented by electronic hardware or a combination of computer software and electronic hardware. Whether the functions are performed by hardware or software depends on particular applications and design constraints of the iviA / a / zuzo / u i ut technical solutions. A person skilled in the art may use different methods to implement the described functions for each particular application, but it is not necessary to consider the implementation beyond the scope of this application. A person skilled in the art can clearly understand that, for the purpose of a convenient and brief description, for a detailed operating process of the above system, apparatus and unit, reference is made to a corresponding process in the above embodiments of the method, and no details are described again herein. In the various embodiments provided in this application, it should be understood that the disclosed system, apparatus and method may be implemented in other ways. For example, the embodiment of the apparatus described is merely an example. For example, division into units is simply a division of logical functions and may be another division in a real implementation. For example, a plurality of units or components may be combined or integrated into another system, or some features may be ignored or not realized. Furthermore, the mutual couplings or direct couplings or communication connections shown or discussed can be implemented through some interfaces. Indirect couplings or communication connections between devices or units can be implemented electronically, mechanically or otherwise. Units described as separate parts may or may not be physically separate, and parts shown as units may or may not be physical units, may be located in one location, or may be distributed across a plurality of network drives. Some or all units can be selected based on actual requirements to achieve the objectives of the modality solutions. Furthermore, the functional units embodying this application may be integrated into a processing unit, or each of the units may exist physically separately, or two or more units may be integrated into one unit. When functions are implemented in the form of a functional unit of software and sold or used as a stand-alone product, the functions may be stored on a computer-readable storage medium. Based on this understanding, the technical solutions of this application essentially, or the conventional technology contributing part, or some of the technical solutions, can be implemented in the form of a computer software product. The computer software product is stored on a storage medium and includes various instructions to instruct a computer device (which may be a personal computer, a server, a network device) to perform all or some of the steps of the methods described in the modalities of this application. The above storage media includes any media that can store program code, such as a USB flash memory drive, removable hard drive, iviA / a / zuzo / ui or Read-Only Memory (ROM). , a Random Access Memory (RAM), a magnetic disk, or an optical disk. The above descriptions are simply specific implementations of this application, however they are not intended to limit the protection scope of this application. Any variation or replacement readily envisioned by a person skilled in the art within the technical scope disclosed in this application must fall within the protective scope of this application. Therefore, the scope of protection of this application must be subject to the scope of protection of the claims.

Claims

1. A direct link configuration method, applied to a first device, wherein the first device comprises one or more STA stations, the first device connects to a third device, the third device comprises a plurality of access points (APs), a second device connects to the third device, the second device comprises a plurality of STAs, and the method characterized in that it comprises: determining at least two tunneled Direct Link Configuration Request TDLS discovery request frames, wherein the TDLS discovery request frame comprises an identifier field indicating an AP on the third device, and different TDLS discovery request frames one by one correspond to different APs on the third device; and sending the at least two TDLS discovery request frames.

2. The method according to claim 1, characterized in that the identifier field is a Basic Service Set Identifier (BSSID), and the BSSID is carried in a Link Identifier Element field of the TDLS Discovery Request Frame.

3. The method according to claim 1 or 2, characterized in that the TDLS discovery request frame comprises a multilink element field, the method element field comprises a type subfield, and the type subfield indicates a tunneled direct link configuration.

4. The method according to any of claims 1 to 3, characterized in that the TDLS discovery request frame comprises the multilink element field comprising an MLD MAC address field, and the MLD MAC address field indicates a MAC address of the third device.

5. The method according to any of claims 1 to 4, characterized in that the first device receives a TDLS discovery response frame from a tunneled direct link configuration response fed back by an STA that is associated with the AP of the third device and that is in the STA plurality of the second device.

6. The method in accordance with any of claims 1 to 5, characterized in that the method further comprises: linking the MAC address of the third device to a TDLS TPK pair key.

7. A direct link addressing method, applied to a second device, characterized in that the second device comprises a plurality of STA stations, the second device connects to a third device, the third device comprises a plurality of AP access points, a first device connects to the third device, the first device comprises one or more STAs, and the method comprises: receiving at least two tunneled Direct Link Configuration Request TDLS discovery request frames, wherein the TDLS discovery request frame comprises an identifier field indicating an AP on the third device, and different TDLS discovery request frames one by one correspond to different APs on the third device;and send, through a STA that is associated with the AP of the third device and that is in the plurality of STAs of the second device, a TDLS discovery response frame of tunneled direct link configuration discovery response.; 8. The method according to claim 7, characterized in that the identifier field is a Basic Service Set Identifier (BSSID), and the BSSID is carried in a Link Identifier Element field of the TDLS Discovery Request Frame.

9. The method according to claim 7 or 8, characterized in that the TDLS discovery request frame comprises a multilink element field, the method element field comprises a type subfield, and the type subfield indicates a tunneled direct link configuration.

10. The method according to any of claims 7 to 9, characterized in that the TDLS discovery request frame comprises the multilink element field comprising an MLD MAC address field, and the MLD MAC address field indicates a MAC address of the third device.

11. The method in accordance with any of claims 7 to 10, characterized in that the method further comprises: linking the MAC address of the third device to a TDLS TPK pair key.

12. A first device, characterized in that the first device comprises one or more STA stations, the first device is connected to a third device, the third device comprises a plurality of access points (APs), a second device is connected to the third device, the second device comprises a plurality of STAs, and the first device comprises: a processing unit, configured to determine at least two tunneled Direct Link Configuration Request TDLS discovery request frames, wherein the TDLS discovery request frame comprises an identifier field indicating an AP on the third device, and different TDLS discovery request frames one by one correspond to different APs on the third device; and a transceiver unit, configured to send the at least two TDLS discovery request frames.

13. The first device according to claim 12, characterized in that the identifier field is a Basic Service Set Identifier (BSSID), and the BSSID is carried in a Link Identifier Element field of the Discovery Request Frame (TDLS).

14. The first device according to claim 12 or 13, characterized in that the TDLS discovery request frame comprises a multilink element field, the method element field comprises a type subfield, and the type subfield indicates a tunneled direct link configuration.

15. The first device according to any of claims 12 to 14, characterized in that the TDLS discovery request frame comprises the multilink element field comprising an MLD MAC address field, and the MLD MAC address field indicates a MAC address of the third device.

16. The first device according to any of claims 12 to 15, characterized in that the transceiver unit is further configured to receive a TDLS discovery response frame from a tunneled direct link configuration response fed back by an STA that is associated with the AP of the third device and is in the plurality of STAs of the second device.

17. The first device according to any one of claims 12 to 16, characterized in that the MAC address of the third device is linked to a TDLSTPK key pair.

18. A second device, characterized in that the second device comprises a plurality of STA stations, the second device connects to a third device, the third device comprises a plurality of AP access points, a first device connects to the third device, the first device comprises one or more STAs, and the second device comprises: a transceiver unit, configured to receive at least two tunneled Direct Link Configuration Request TDLS discovery request frames, wherein the TDLS discovery request frame comprises an identifier field indicating an AP on the third device, and different TDLS discovery request frames one by one correspond to different APs on the third device,where an STA that is associated with the AP of the third device and that is in the plurality of SSTAs of the second device sends a TDLS discovery response frame of tunneled direct link configuration.

19. The second device according to claim 18, characterized in that the identifier field is a Basic Service Set Identifier (BSSID), and the BSSID iviA / a / zuzo / ui ut is carried in a Link Identifier Element field of the TDLS Discovery Request Frame.

20. The second device according to claim 18 or 19, characterized in that the TDLS discovery request frame comprises a multilink element field, the method element field comprises a type subfield, and the type subfield indicates a tunneled direct link configuration.

21. The second device according to any of claims 18 to 20, characterized in that the TDLS discovery request frame comprises the multilink element field comprising an MLD MAC address field, and the MLD MAC address field indicates a MAC address of the third device.

22. The second device according to any one of claims 18 to 21, characterized in that the MAC address of the third device is linked to a TDLS TPK pair key.

23. A direct link addressing apparatus, characterized in that the direct link addressing apparatus comprises units or modules configured to perform the method in accordance with any of claims 1 to 11.

24. A direct link addressing apparatus, characterized in that the direct link addressing apparatus comprises a processor, and the processor is coupled to a memory; the memory is configured to store a computer program; and the processor is configured to execute the computer program stored in the memory, such that the direct link addressing apparatus performs the method in accordance with any one of claims 1 to 11.

25. A computer-readable storage medium, characterized in that the computer-readable storage medium comprises computer programs or instructions; and when the computer programs or instructions are executed on a computer, the computer is activated to perform the method in accordance with any one of claims 1 to 11.

26. A computer program product, characterized in that the computer program product comprises computer programs or instructions; and when the computer programs or instructions are executed on a computer, the computer is activated to perform the method in accordance with any one of claims 1 to 11.

27. A chip, characterized in that the chip comprises a processor and an input / output port, when computer programs or instructions are executed, the chip is activated to perform the method in accordance with any of claims 1 to 11.

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