CN116762466A

CN116762466A - Apparatus and method for multilink transmission

Info

Publication number: CN116762466A
Application number: CN202280009918.5A
Authority: CN
Inventors: 斯蒂芬·麦肯; 麦克·蒙特穆罗
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2021-01-20
Filing date: 2022-01-20
Publication date: 2023-09-15
Also published as: WO2022157239A1; EP4278705A1

Abstract

The present disclosure relates to multilink transmission in wireless communications. To this end, the present disclosure proposes a wireless device for transmitting a multi-link ML configuration, wherein the wireless device corresponds to one or more accessory APs, the wireless device configured to: the wireless device obtains an ML configuration, wherein the ML configuration indicates whether one or more accessory APs are operating a legacy BSS; and the wireless device transmitting the ML configuration within a subfield of the ML element.

Description

Apparatus and method for multilink transmission

Technical Field

The present disclosure relates generally to wireless communications, and more particularly to multilink transmission.

Background

The wireless communication system to which the embodiments of the present disclosure are applicable may be a wireless local area network (wireless local area network, WLAN) system or a cellular network system. The method of transmitting the group addressing traffic (group addressed service) for broadcast and multicast frames may be implemented by a communication device in a wireless communication system or by a chip or processor in the communication device. The communication device may be a wireless communication device that supports parallel transmissions over a variety of links. For example, it is referred to as a multi-link device or a multi-band device. The multi-link device has higher transmission efficiency and higher throughput than a device supporting only single link transmission.

The ultra high throughput (Extremely High Throughput, EHT) Task Group (TG) recently initiated standardized activity in the IEEE 802.11WLAN project and this TG was called 802.11be. One of the new basic features is the creation of Multi-Link devices (MLD). This is described as a WLAN entity with multiple radio links to another MLD or another MLD entity.

Although the latest draft of p802.11be describes some basic requirements of MLD operation, it does not cover how to transmit group-addressed frames.

Disclosure of Invention

In view of the above limitations, embodiments of the present disclosure are directed to introducing a solution for multilink transmission. In particular, it is an object to prevent unnecessary duplication of group-addressed frames.

This object is achieved by the embodiments provided in the appended independent claims. Advantageous embodiments of the embodiments are further defined in the dependent claims.

A first aspect of the present disclosure provides a wireless device for transmitting a multi-link ML (multi-link) configuration, wherein the wireless device corresponds to one or more accessory APs, the wireless device configured to: the wireless device obtains an ML configuration, wherein the ML configuration indicates whether one or more accessory APs are operating a legacy BSS; and the wireless device transmitting the ML configuration within a subfield of the ML element.

The new functionality provided by the present disclosure within a wireless device (e.g., AP MLD) prevents the duplication of unnecessary group addressing frames. The operation of this function depends on whether traffic is routed from the backhaul LAN connection to the legacy STA attached to the AP MLD.

Embodiments of the present disclosure propose a wireless device for multilink transmission, which may operate accordingly as described in the first aspect and its implementation forms.

In an implementation form of the first aspect, the ML configuration further indicates whether the legacy BSS of the one or more accessory APs is in the same ESS as the BSS of the wireless device or in a different ESS than the ESS of the BSS of the wireless device.

In an implementation form of the first aspect, the first value of the subfield indicates that one or more accessory APs are operating a legacy BSS in the same ESS as the wireless device; the second value of the subfield indicates that one or more accessory APs are operating a legacy BSS in an ESS different from the ESS of the wireless device; and/or a third value of the subfield indicates that one or more accessory APs are not operating a legacy BSS.

In an implementation form of the first aspect, the wireless device is further configured to refrain from transmitting the group addressing frame when one or more accessory APs are operating a legacy BSS in the same ESS as the wireless device.

In an implementation form of the first aspect, the wireless device is further configured to transmit a group key based on the value of the subfield.

The new functionality provided by the present disclosure in a non-AP MLD, upon receiving configuration information from the AP MLD, determines which keys (e.g., GTK, IGTK) are negotiated based on the configuration of the AP MLD and the affiliated AP.

The wireless device of the present disclosure provides a way to save radio resources and can prevent unnecessary transmission and reception of duplicate group addressing frames in both AP MLD and non-AP MLD.

A second aspect of the present disclosure provides a wireless device for receiving a multi-link ML configuration, wherein the wireless device corresponds to one or more dependent STAs, the wireless device configured to: the wireless device receives an ML configuration, wherein the ML configuration indicates whether one or more accessory APs are operating a legacy BSS, wherein the ML configuration is carried on subfields of an ML element; and the wireless device performing an interaction with another wireless device based on the ML configuration.

In an implementation form of the second aspect, the ML configuration further indicates whether the legacy BSS of the one or more accessory APs is in the same ESS as the BSS of the wireless device or in a different ESS than the ESS of the BSS of the wireless device.

In an implementation form of the second aspect, the first value of the subfield indicates that one or more accessory APs are operating a legacy BSS in the same ESS as the wireless device; the second value of the subfield indicates that one or more accessory APs are operating a legacy BSS in an ESS different from the ESS of the wireless device; and/or a third value of the subfield indicates that one or more accessory APs are not operating a legacy BSS.

A third aspect of the present disclosure provides a method of transmitting a multilink ML configuration performed by a wireless device, wherein the wireless device corresponds to one or more accessory APs, the method comprising: the wireless device obtains an ML configuration, wherein the ML configuration indicates whether one or more accessory APs are operating a legacy BSS; and the wireless device transmitting the ML configuration within a subfield of the ML element.

An implementation form of the method of the third aspect may correspond to an implementation form of the wireless device of the first aspect as described above. The method of the third aspect and its implementation forms achieve the same advantages and effects as described for the wireless device of the first aspect and its implementation forms.

A fourth aspect of the present disclosure provides a method performed by a wireless device for receiving a multi-link ML configuration, wherein the wireless device corresponds to one or more dependent STAs, the method comprising: the wireless device receives an ML configuration, wherein the ML configuration indicates whether one or more accessory APs are operating a legacy BSS, wherein the ML configuration is carried on subfields of an ML element; and the wireless device performing interactions with other wireless devices based on the ML configuration.

An implementation form of the method of the fourth aspect may correspond to an implementation form of the wireless device of the second aspect as described above. The method of the fourth aspect and its implementation forms achieve the same advantages and effects as described for the wireless device of the second aspect and its implementation forms.

A fifth aspect of the present disclosure provides a computer program product comprising program code for performing the method according to any implementation form of the third and third aspects, or any implementation form of the fourth and fourth aspects, when implemented on a processor.

A sixth aspect of the present disclosure provides a computer readable storage medium storing a computer program which, when run on a computer, is capable of performing the method according to any implementation form of the third and third aspects or any implementation form of the fourth and fourth aspects.

A seventh aspect of the present disclosure provides a chip system comprising a processor configured to invoke a computer program from a memory and to run the computer program to cause a communication device on which the chip system is installed to perform the method according to any of the implementation forms of the third aspect and the third aspect or any of the implementation forms of the fourth aspect and the fourth aspect as described above.

It should be noted that all devices, elements, units and means described in this disclosure may be implemented in software or hardware elements or any kind of combination thereof. All steps performed by the various entities described in this disclosure, as well as functions described as performed by the various entities, are intended to mean that the various entities are adapted or configured to perform the respective steps and functions. Even though in the following description of specific embodiments, specific functions or steps to be performed by external entities are not reflected in the description of specific detailed elements of the entity performing the specific steps or functions, it should be clear to a skilled person that these methods and functions may be implemented in respective software or hardware elements or any kind of combination thereof.

Drawings

The above aspects and embodiments of the present disclosure will be described in the following description of specific embodiments with reference to the drawings, in which

Fig. 1a shows a multi-link device (MLD) architecture.

Fig. 1b shows an example of establishing a 3-link connection between an AP MLD and a non-AP MLD.

Fig. 2 illustrates a simple authentication protocol for establishing a secure connection between a non-AP STA and an AP.

Fig. 3 shows another example of an MLD configuration.

Fig. 4 shows scenario 1 of MLD behavior.

Fig. 5 shows a group addressing frame transmitted by the AP MLD.

Fig. 6 shows scenario 2 of MLD behavior.

Fig. 7 shows a group addressing frame transmitted by the AP MLD.

Fig. 8 shows another way of transmitting a group addressing frame.

Fig. 9 shows scenario 3 of MLD behavior.

Fig. 10 shows a group addressing frame transmitted by the AP MLD.

Fig. 11 illustrates a method of multilink transmission.

Fig. 12a shows the format of the new group addressing configuration subfield in the ML element frame.

Fig. 12b shows subdivision (break down) of the GA configuration field in the ML element.

Fig. 13 illustrates a wireless device 500 according to an embodiment of the present disclosure.

Fig. 14 shows a schematic structural diagram of a multi-link device according to an embodiment of the present disclosure.

Detailed Description

Exemplary embodiments of a method, apparatus and program product for ML transmission in a communication system are described with reference to the accompanying drawings. While this description provides detailed examples of possible implementations, it should be noted that these details are intended to illustrate and in no way limit the scope of the disclosure.

In addition, an embodiment/example may refer to other embodiments/examples. For example, any description including, but not limited to, terms, elements, processes, explanations, and/or technical advantages mentioned in one embodiment/example apply to other embodiments/examples.

Fig. 1a shows a multi-link device (MLD) architecture. The AP MLD includes one or more accessory APs. The STA MLD includes one or more dependent STAs.

In a WLAN, it is typical that an Access Point (AP) MLD connects to a non-AP MLD (or WLAN terminal) using 2 radio links in the 2.4GHz and 5GHz WLAN frequency bands. The individual radio links are called links. The radio functional entities within the AP MLD are called affiliated APs. And the AP MLD and the non-AP MLD form a BSS having an SSID (e.g., SSIDx).

It is also intended that each accessory AP may also serve legacy non-AP STAs. For example, an AP MLD with a 2.4GHz radio link may also serve as a legacy AP serving legacy 802.11ax non-AP STAs. In this case, the functional entity implementing the 2.4GHz radio link is an accessory AP within the AP MLD. The functional entity that implements the 5GHz (or 6GHz or other frequency) radio link is also an accessory AP within the AP MLD.

The operation of MLD is different from the operation in two logical STAs in the same physical entity, e.g., two non-AP STAs in the same handset (handset). Within the MLD, traffic is coordinated between the two links and a security association is maintained between them. This provides some benefits over the virtual STA concept.

For ease of description, in this disclosure, a multilink device, i.e., an AP (e.g., a new type of AP as defined in 802.11 be), may be referred to as a multilink AP, a multilink AP device, or an AP multilink device (AP MLD). The multi-link device belonging to the non-AP STA may be referred to as a multi-link STA, a multi-link STA device, or an STA multi-link device (STA MLD). For ease of description, the "multi-link device includes a member STA" will also be described in the embodiments of the present disclosure as "multi-link device includes STA" simply.

For example, the multi-link device herein may be a single antenna device or a multi-antenna device. For example, a device having more than two antennas may be used. In the embodiment of the disclosure, the number of antennas included in the multi-link device is not limited. In embodiments of the present disclosure, a multi-link device may allow network traffic for the same network to be transmitted on different links, and may even allow the same data packet to be transmitted on different links. Alternatively, network traffic for the same network cannot be transmitted on different links, but network traffic for different networks may be transmitted on different links.

In this example, the AP MLD has three affiliated APs. AP 1 operates in the 2.4GHz band, AP 2 operates in the 5GHz band, and AP 3 operates in the 6GHz band. The non-AP STA 1 attached to the non-AP MLD transmits an association request frame to the AP 1 attached to the AP MLD, i.e., sets a transmitter Address (Transmitter Address, TA) of the association request frame to the MAC Address of the non-AP STA 1 and sets a Receiver Address (RA) of the association request frame to the MAC Address of the AP 1. The association request frame includes complete information of the non-AP STA 1, the non-AP STA 2, and the non-AP STA 3 to request three links to be established (one link between the AP 1 and the non-AP STA 1, one link between the AP 2 and the non-AP STA 2, and one link between the AP 3 and the non-AP STA 3) and ML elements indicating MLD MAC addresses of the non-AP MLD. AP 1 attached to the AP MLD transmits an association response frame (Association Response frame) to the non-AP STA 1 attached to the non-AP MLD, i.e., sets the TA of the association response frame to the MAC address of AP 1 and sets the RA of the association response frame to the MAC address of the non-AP STA 1 to indicate that the multilink establishment was successful.

Fig. 2 illustrates a simple authentication protocol for establishing a secure connection between a non-AP STA and an AP. The process shown in fig. 2 is referred to as a 4-way handshake. It is used to establish a secure connection between a non-AP STA and an AP.

In this process, the AP and non-AP STAs exchange 4 messages to derive keying material and establish a security association. For infrastructure connection, a first message is transmitted from the AP to the non-AP STA and contains a random number generated by the AP, referred to as an authentication random number (Authenticator Nonce, ANonce). The non-AP STA receives and validates the first message, generates a random number, referred to as a request random number (SNonce), calculates a message integrity code (Message Integrity Code, MIC) based on the content of the second message, and transmits the second message to the AP. The AP receives and verifies the second message; and finishing the derivation of the encryption key and transmitting a third message to the non-AP STA. The non-AP STA receives and validates the third message and transmits a fourth message to the AP to confirm that the 4-way handshake has completed successfully. These messages are used to exchange security information. The purpose of the 4-way handshake is to create security keys (e.g., group temporary key (Group Temporal Key, GTK) and integrity group temporary key (Integrity Group Temporal Key, IGTK), among other keys not shown) between the AP (authenticator) and the non-AP STA (supplicant). These keys are then used to encrypt data between the AP and the STA. GTK, IGTK are carried within Key Data Elements (KDEs), and IEEE 802.11 defines various types of KDEs for various keys, with GTK, IGTK being two keys.

During 802.11 association (i.e., by exchange of association requests and association requests/responses), the contents of the 4-way handshake message and the algorithm used to derive the keying material are negotiated between the AP and the non-AP STAs prior to the 4-way handshake. Since no status code is used in the 4-way handshake, both the AP and the non-AP STAs need to know how the subfields are encoded before the 4-way handshake begins so that they do not erroneously decode every message of the sequence.

Another process known as group key handshake is also used in security association. The group key handshake is a simplified two message exchange for updating the group key (e.g., GTK, IGTK) when the original group key needs to be refreshed. The group key handshake is initiated by the AP to each associated STA and occurs only after a successful 4-way handshake.

Fig. 3 shows another example of an MLD configuration. In this example, a single piece of hardware is used for deployment. The AP MLD supports 2 radios, MLD configurations, and/or legacy STA connections operating in the 2.4GHz band and the 5GHz band. In addition, the AP MLD may support operation of multiple BSSs on the same radio (using the same physical hardware, under different packet protocols), e.g., a home network (BSS 1: AP MLD and non-AP MLD) and a guest legacy network (BSS 2:2.4GHz AP and one link of legacy STA 1) on the same radio.

Although fig. 3 shows only a single ESS, the ESS is configured such that BSSs advertised by AP MLD, 2.4GHz accessory AP, and 5GHz accessory AP (advertisement), respectively, all use the same SSID (e.g., SSIDx) to advertise the same ESS.

Both accessory APs transmit identifiers for the MLD BSS and the legacy BSS. If the accessory AP and AP MLD support multiple BSSs, this may be done using a multi-link element and possibly using a modified multi-BSS element. Each accessory AP uses a unique MAC address that is different from the MLD MAC address.

Legacy STAs are associated with a 2.4GHz AP (accessory AP) or with a 5GHz AP (another accessory AP). The non-AP MLD is associated with an AP MLD on a separate BSS.

For wired gaws (Gateway) on LANs (Local Area Network, local area networks), each affiliated AP is logically shown as a separate portal (each bridging traffic to the LAN independently), so they can be a single physical LAN port. The BSSIDs for the 2.4GHz accessory AP, the 5GHz accessory AP, and the AP MLD all need to be different. Otherwise, legacy STAs may encounter problems.

MLD association

The non-AP MLD is assigned a single MAC address and is associated with an AP MLD having its non-AP MLD MAC address. The dependent STAs of the non-AP MLD are associated with respective dependent APs of the AP MLD.

This is similar to the way today's multiband clients operate-one MAC address for different bands. Once associated, this allows non-AP STAs to switch between 2.4GHz AP and 5GHz AP without losing IP connectivity. For non-AP MLDs, this configuration has the further advantage of allowing the non-AP MLD to switch between AP MLD, 2.4GHz AP and 5GHz AP.

MLD BSSID

Since the AP MLD BSSID ("bssid_mld" in fig. 3) is used in MAC frame addressing, the AP MLD bridges traffic from the non-AP MLD to/from the LAN.

non-AP MLD association

The non-AP MLD is associated with an AP MLD in the MLD BSS. The non-AP MLD and the AP MLD establish a security association (security association, SA) comprising GTK and IGTK.

With respect to fig. 3, depending on the configuration of the AP MLD, the GTK and IGTK are associated with bssid_mld or with each of bssid_24 and bssid_5. Thus, depending on the configuration of the AP MLD, the non-AP MLD may also need to transmit GTKs and IGTKs for the MLD or for the 2.4GHz auxiliary link and 5GHz auxiliary link.

GTK and IGTK may also be referred to as (GTK, IGTK) _{BSSID_MLD} ，(GTK，IGTK) _{BSSID_24} And (GTK, IGTK) _{BSSID_5} 。

Group addressing traffic

AP MLD use (GTK, IGTK) _{BSSID_MLD} Traffic is encrypted and MLD BSS traffic may be sent over any link (or replicated over all links). Accessory AP uses key pair [ or (GTK, IGTK) _{BSSID_24} Or (GTK, IGTK) _{BSSID_5} ]Traffic is encrypted. Each dependent STA filters group addressing data traffic of BSSs not directed to the dependent STA and receives the group addressing management traffic.

When the MLD architecture allows affiliated APs to operate their own BSSs with the MLD BSS, it is possible to replicate the group addressing traffic. With respect to the MLD architecture in fig. 5 (scenario 2), a group-addressed frame may be replicated on two radio links (attached links) and then replicated again at the MLD link layer, resulting in multiple copies of the same group-addressed frame.

However, this is a waste of resources for both the power and processing of the radio medium as well as the transmitter and receiver.

When the AP MLD and accessory AP operate the BSS in the same ESS, the broadcast/multicast data traffic will double (AP MLD broadcast and accessory AP broadcast). Legacy STAs associated with the accessory AP will receive group-addressed traffic from the accessory AP.

However, the non-AP MLD will receive repeated group addressing traffic from the AP MLD and each accessory AP. Since the non-AP MLD needs to listen to all group-addressed frames (e.g., spectrum management frames) for management purposes, it will receive and parse all of these frames, even repeated frames.

The present disclosure provides new functionality within the AP MLD to prevent the duplication of unnecessary group addressing frames. The operation of this function depends on the configuration of the AP MLD and/or whether traffic is routed from the backhaul LAN connection to the legacy STAs attached to the AP MLD. The configuration information is advertised to the non-AP MLD.

New functionality is added in the non-AP MLD to determine from which BSS to derive a security key (e.g., GTK, IGTK) to properly decrypt the group-addressed frame based on the configuration of the AP MLD. This configuration information is received from the AP MLD.

For group addressing traffic, there are at least three topological scenarios for MLD behavior. These are considered below.

Fig. 4 shows scenario 1 of MLD behavior. In scenario 1, the accessory AP does not operate the BSS. In this scenario, only MLDs without a legacy BSS are running.

Accessory AP generates beacon frames and probe response frames containing broadcast traffic and AP MLD BSSID protected using AP MLD key pair (GTK, IGTK).

Add a new field to the Multilink (ML) element that can signal (as a possible configuration option) that the BSS of the AP MLD and the BSS of the accessory AP (legacy BSS) are not part of the same BSS. This new field is described below.

Accessory AP broadcasts a beacon frame to its BSS (which needs to be clarified what the beacon contains), but does not accept the association. The reply has an association request with a status code of REFUSED or the like.

The BSSID of all group-addressed frames is the AP MLD BSSID.

Fig. 5 shows a group addressing frame transmitted by the AP MLD. The affiliated APs (AP 1 and AP 2) on each link transmit their own beacon frames (shown in red and green) and a copy of the group addressed frames from LAN1 forwarded from the AP MLD. In this scenario, the group addressing frame needs to be repeated in order to prevent one of the radio links between the AP MLD and the non-AP MLD from breaking.

Fig. 6 shows scenario 2 of MLD behavior. In scenario 2, the accessory AP is running a BSS that is part of the same ESS as the AP MLD. In this scenario as shown, there are an MLD BSS and two legacy BSSs.

Only one BSS is an MLD BSS. However, the MLD BSS is part of the same ESS as the affiliated AP BSS.

There is a field in the multilink element to indicate that the accessory AP BSS is in the same ESS.

The group addressing traffic of the AP MLD is transmitted on the link corresponding to the AP MLD BSSID.

Group addressing traffic for other BSSs is transmitted by the associated accessory AP using the BSSID corresponding to the BSS.

Fig. 7 shows a group addressing frame transmitted by the AP MLD. The affiliated APs (AP 1 and AP 2) on each link transmit their own beacon frames and a copy of the group addressed frames from LAN1 forwarded from the AP MLD. In addition, AP1 and AP2 also receive their own copies of the group addressed frames from LAN1 because they are configured to serve legacy STAs. Legacy STAs cannot receive traffic from the AP MLD because the legacy frames are addressed differently than the AP MLD BSS.

Thus, repeated group addressing frames appear on each secondary link.

Fig. 8 shows another way of group addressing frame transmission. The affiliated APs (AP 1 and AP 2) on each link transmit their own beacon frames. However, GA frames within the AP MLD are suppressed. This removes repeated GA frames on each secondary link.

Fig. 9 shows scenario 3 of MLD behavior. In scenario 3, the accessory AP is running a BSS that is not part of the same ESS as the AP MLD.

Accessory APs address frames for their respective BSS transmission groups. The AP MLD does not transmit a group addressing data frame on the BSS.

The field in the multilink element informs that the BSS of the affiliated AP is not a member of the same ESS as the AP MLD.

While such a scenario may not be common in practice, it is important to recognize that different AP MLD configurations may change the manner in which group addressed frames are processed.

Fig. 10 shows a group addressing frame transmitted by the AP MLD. The affiliated APs (AP 1 and AP 2) on each link transmit their own beacon frames, as well as copies of the group addressed frames from LAN1 forwarded from the AP MLD. In addition, AP1 and AP2 also receive their own copies of the group addressed frames originating from LAN2 and LAN3, respectively, because they are configured to serve legacy STAs. Thus, all group addressing frames are transmitted because they originate from different LANs and the AP MLD again requires redundancy of its group addressing frames on the accessory link.

Therefore, repeated GA frames should not be prevented in the AP MLD.

Fig. 11 illustrates a method of multilink transmission. The method comprises the following steps of S101: the ML configuration is transmitted. Wherein the ML configuration indicates whether one or more accessory APs are operating a legacy BSS. The ML configuration is carried on subfields of the ML element.

Furthermore, the method may further comprise: interaction with another wireless device is performed based on the ML configuration. For example, the method may further include S102: a 4-way handshake or a group key handshake is performed based on the ML configuration.

The above steps may be performed by the MLD. Interaction may be between two MLDs (e.g., an AP MLD and a non-AP MLD).

In addition, the ML configuration also indicates whether the legacy BSS of the one or more affiliated APs is in the same ESS as the BSS of the wireless device or in a different ESS than the ESS of the BSS of the wireless device.

The ML configuration is used to determine whether to transmit one or more group-addressed frames. Therefore, the ML configuration may also be referred to as a Group Address (GA) configuration. Further, detailed uses of ML configurations are described in other relevant portions of the present disclosure. Such as an announcement of a group addressing configuration, a blocking of group addressing frame transmissions, a GA configured based 4-way handshake, or a GA configured based GTK, IGTK security association.

Fig. 12a shows the format of the new group addressing configuration subfield in the ML element frame. The length of the subfields may be one or more octets, or several bits (2 or 3 bits). The values of the subfields are as follows:

a first value (e.g., 0) indicates: one or more accessory APs do not operate a legacy BSS.

A second value (e.g., 1) indicates: one or more accessory APs operate a legacy BSS in the same ESS as the AP MLD.

A third value (e.g., 2) indicates: one or more accessory APs operate a legacy BSS in a different ESS than the ESS of the AP MLD.

The value of the subfield may also be used to indicate whether one or more accessory APs are operating a legacy BSS in the same ESS as the non-AP MLD. Accordingly, those skilled in the art will recognize a similar definition in light of the above description.

The backward compatible way to advertise the GA configuration subfield is to transmit it as ML element of the MLD BSS. As shown in fig. 12b, this subfield is added to the existing IEEE 802.11be ML element.

Fig. 12b shows subdivision of the GA configuration field in the ML element. The ML element includes at least one of the following fields: element ID (Element ID), length (Length), element ID extension (Element ID Extension), multi-Link Control (Multi-Link Control), common information (Common Info), link Info.

The element ID and element ID extension fields are defined to indicate that the frame is a multi-link (ML) element. The length field indicates the length of the ML element.

The multi-link control subfield includes at least one of a Type (Type) subfield, an MLD MAC address presence (MLD MAC Address Present) subfield, and a Reserved (Reserved) subfield. When the value of the type subfield is equal to 1, the link information field includes an optional subelement (Optional Subelement). The MLD MAC address present subfield indicates whether the MLD MAC address is present in another portion of the ML element. The reserved subfield is reserved for future use and is not defined.

The general information field defines information of all ML elements.

Each optional sub-element includes at least one sub-element ID (Subelement ID) sub-field, and a Length (Length) sub-field and Data (Data). When the subelement ID subfield is equal to 1, the data subfield contains the GA configuration value.

Announcement of group addressing configuration

The AP MLD advertises (or transmits, or broadcasts) a new subfield (group addressing configuration) within the multi-link (ML) element that indicates information about the configuration of the AP MLD, the LAN, and any legacy STAs (e.g., the configuration as shown in fig. 3/5/8). If necessary, the non-AP MLD receives the configuration of the AP MLD before the 4-way handshake starts, so that the non-AP MLD can during the 4-way handshake and the subsequent group key handshakeSets of authentication keys (e.g. GTK, IGTK) _{BSSID_MLD} Or (GTK, IGTK) _{BSSID_24} And (GTK, IGTK) _{BSSID_5} ))。

In message 3 of fig. 2, different subfield formats are used for transmission (GTK, IGTK) _{BSSID_MLD} Or (GTK, IGTK) _{BSSID_24} (GTK, IGTK) _{BSSID_5} . Information about the subfield format is not transmitted within the message 3 itself.

Since there are now two choices for the subfield format in the message 3 that may be received, the non-AP MLD needs to know the group addressing configuration before the 4-way handshake starts so that it can determine how to decode the subfields correctly.

The ML element with this subfield will be transmitted by the AP MLD in the following way: beacon frame, probe response frame. Alternatively, this subfield may be advertised in the beacon and probe response frames as a new subfield within the existing MBSSID (multiple BSSID) element, as an additional optional subfield at the end of the element.

The AP MLD receives the GA configuration subfield in a (re) association request from the non-AP MLD. The AP MLD may set a status code based on the received correct GA configuration subfield value to indicate success or rejection.

If the GA configuration subfield value received in the (re) association request is valid, the AP MLD may respond with the status code SUCCESS. If the value of the GA configuration subfield value received in the (re) association request is invalid, the AP MLD may respond with a REFUSED_CAPABLITIES_MISSATCH status code or another valid status code. Alternatively, a new status code may be used in the (re) association exchange, e.g. group_ ADDRESSED _ml_configuration_incompe.

If the subfield is set to 0 or 2, then AP MLD use (GTK, IGTK) _{BSSID_MLD} The group addressing traffic for transmission is encapsulated.

If the subfield is set to 1, the AP MLD does not transmit group addressing traffic, but instead relies on the affiliated AP to encapsulate the group addressing traffic using the link-specific key for transmission, (e.g., (GTK, IGTK) _{BSSID_24} ，(GTK，IGTK) _{BSSID_5} ))。

Preventing group addressing frame transmission

When the configuration of the AP MLD is that of the usage scenario 2, the group addressing frame from the LAN is not forwarded to any affiliated AP through the AP MLD. The configuration of the AP MLD may be set by a user installing the AP MLD or by a user maintaining the AP MLD through an external management system. Automatic reconfiguration may also occur inside the AP MLD, as it monitors the number of LAN connections and the number of legacy STAs connected.

The non-AP MLD receives the group addressing configuration subfield in a beacon and/or probe response frame.

The non-AP MLD transmits a (re) association request frame to the AP MLD having an ML element including a group addressing configuration subfield set to a value received in a beacon or probe response frame received from the AP MLD. The non-AP MLD may receive the ML element with the group addressing configuration subfield in a (re) association response frame transmitted by the AP MLD.

GA configuration-based 4-way handshake

During the 4-way handshake when the GA configuration subfield value is 0 or 2:

AP MLD is transmitted in message 3 of the 4-way handshake (GTK, IGTK) _{BSSID_MLD} 。

Encapsulation of GA frames for transmission is handled by the AP MLD.

The non-AP MLD verifies that it only receives one set of MLD keys. Each time a receiving STA needs a key to decapsulate the GA frame.

non-AP MLD usage (GTK, IGTK) _{BSSID_MLD} The group addressing traffic received from the AP-MLD is decapsulated.

During the 4-way handshake when the GA configuration subfield value is 1:

in a 4-way handshake, the AP MLD coordinates with the accessory AP to transmit a link-specific group key (e.g., GTK, IGTK) _{BSSID_24} ，(GTK，IGTK) _{BSSID_5} ))。

AP MLD does not transmit nor encapsulate GA frames.

To avoid duplication of data frames on the wireless medium, encapsulation of GA frames is handled by each accessory AP.

The non-AP MLD verifies that it received the set of link-specific keys. Each time a receiving STA needs an appropriate key to decapsulate the GA frame.

non-AP MLD receives group-addressed traffic transmitted by the affiliated AP and uses a link-specific key (e.g., GTK, IGTK) _{BSSID_24} ，(GTK，IGTK) _{BSSID_5} ) The group addressing traffic is decapsulated.

GTK and IGTK security association based on GA configuration

The non-AP MLD is associated to an AP MLD on the MLD BSS.

non-AP MLD and AP MLD establish SA comprising according to configuration (GTK, IGTK) _{BSSID_24} And (GTK, IGTK) _{BSSID_5} Or associated with AP MLD (GTK, IGTK) _{BSSID_MLD} 。

The non-AP MLD uses bssid_mld as a destination address (destination address, DA) and BSSID to establish a network and communication over the LAN.

The group key handshake is used to update the GTK, IGTK keys to refresh the keys. The non-AP MLD needs to know the value of the received GA configuration frame to be able to correctly decode the subfields containing GTK, IGTK in the group key handshake received from the AP MLD.

The new functionality provided by the present disclosure within the AP MLD prevents the duplication of unnecessary group addressing frames. The operation of this function depends on whether traffic is routed from the backhaul LAN connection to the legacy STA attached to the AP MLD.

The new functionality provided by the present disclosure in a non-AP MLD, upon receiving configuration information from the AP MLD, determines which keys (e.g., GTK, IGTK) are negotiated based on the configuration of the AP MLD.

The method and apparatus of the present disclosure provide a way to save radio resources and can prevent the unnecessary transmission and reception of duplicate group addressing frames in both AP MLD and non-AP MLD.

Fig. 13 illustrates a wireless device 500 according to an embodiment of the present disclosure. The wireless device 500 may include processing circuitry 501 configured to perform, implement, or initiate various operations of the wireless device 500 described herein. The processing circuitry may include hardware and software. The hardware may include analog circuitry or digital circuitry, or both analog and digital circuitry. The digital circuitry may include components such as an application-specific integrated circuit (ASIC), field-programmable array (FPGA), digital signal processor (digital signal processor, DSP), or multi-purpose processor. The wireless device 500 may also include memory circuitry that stores one or more instructions executable by the processor or processing circuitry, particularly under the control of software. For example, the memory circuit may include a non-transitory storage medium storing executable software code that, when executed by a processor or processing circuit, causes various operations of the wireless device 500 to be performed. In one embodiment, a processing circuit includes one or more processors and a non-transitory memory coupled to the one or more processors. The non-transitory memory may carry executable program code that, when executed by one or more processors, causes the wireless device 500 to perform, implement, or initiate the operations or methods described herein. The wireless device 500 may also include an interface circuit 502 for communicating with another wireless device (e.g., wireless device 400).

Fig. 14 shows a schematic structural diagram of a multi-link device according to an embodiment of the present disclosure. As shown in fig. 14, the multi-link device may include at least one processor 1401, at least one communication interface 1402, at least one memory 1403, and/or at least one bus 1404.

The present disclosure has been described in connection with various examples that are set forth as examples and implementations. However, other variations can be understood and effected by those skilled in the art and practicing the claimed disclosure, from a study of the drawings, the disclosure and the independent claims. In the claims and in the description, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. A single element or other unit may fulfill the functions of several entities or items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

Furthermore, any method according to embodiments of the present disclosure may be implemented in a computer program having code means, which when run by processing means causes the processing means to perform the steps of the method. The computer program is embodied in a computer readable medium of a computer program product. A computer readable medium may include essentially any Memory, such as ROM (Read-Only Memory), PROM (Programmable Read-Only Memory), EPROM (Erasable PROM), flash Memory, EEPROM (Electrically Erasable PROM ), or hard disk drive.

Furthermore, the skilled person will appreciate that embodiments of the wireless device 500 comprise the necessary communication capabilities in the form of e.g. functions, means, units, elements etc. for performing the solution. Examples of other such devices, units, elements, and functions are: processors, memories, buffers, control logic, encoders, decoders, rate matchers, rate reduction matchers, mapping units, multipliers, decision units, selection units, switches, interleavers, de-interleavers, modulators, demodulators, inputs, outputs, antennas, amplifiers, receiver units, transmitter units, DSPs, trellis-coded modulation (TCM) encoders, TCM decoders, power supply units, feeders, communication interfaces, communication protocols, etc., which are suitably arranged together to execute the solution.

In particular, the processor of wireless device 500 may each include one or more instances of, for example, a central processing unit (Central Processing Unit, CPU), processing unit, processing circuit, processor, application Specific Integrated Circuit (ASIC), microprocessor, or other processing logic that may interpret and execute instructions. The expression "processor" may thus denote a processing circuit comprising a plurality of processing circuits, e.g. any, some or all of the processing circuits described above. The processing circuitry may also perform data processing functions for inputting, outputting, and processing data, including data buffering and device control functions, such as call processing control, user interface control, and the like.

There is provided a communication device (e.g. a base station or access point capable of performing the above method) comprising at least one of: a bus, a processor, a storage medium, a bus interface, a network adapter, a user interface, and an antenna (or transceiver, transmitter, and/or receiver), wherein the bus is configured to connect the processor, the storage medium, the bus interface, and the user interface; the processor is configured to perform the above method; the storage medium is configured to store an operating system and data to be transmitted or received; the bus interface is connected to the network adapter; the network adapter is configured to implement a signal processing function of a physical layer in the wireless communication network; the user interface is configured to connect to a user input device; and the antenna is configured to transmit and receive signals.

Another aspect of the present disclosure provides a computer readable storage medium storing instructions which, when run on a computer, perform the above method.

Another aspect of the present disclosure provides a computer program product comprising instructions, wherein the computer performs the above method when the computer program product is run on a computer.

Another aspect of the present disclosure provides a computer program, wherein the computer performs the above method when the computer program runs on a computer.

The foregoing embodiments may be implemented in whole or in part using software, hardware, firmware, or any combination thereof. When the embodiments are implemented in software, the embodiments may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the programs or functions in accordance with embodiments of the present disclosure will be wholly or partially generated. The computer may be a general purpose computer, a special purpose computer, a computer network, or other programmable apparatus. The computer instructions may be stored in a computer-readable storage medium or transmitted from the computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions may be transmitted from a website, computer, server, or data center to another website, computer, server, or data center by a wired (e.g., coaxial cable, fiber optic, or digital subscription line (digital subscriber line, DSL)) or wireless (e.g., infrared, radio, or microwave) means. Computer readable storage media can be any available media that can be accessed by a computer or can be a data storage device, such as a server or data center, that integrates one or more available media.

Claims

1. A wireless device for transmitting a multi-link ML configuration, wherein the wireless device corresponds to one or more accessory APs, the wireless device configured to:

the wireless device obtaining the ML configuration, wherein the ML configuration indicates whether the one or more accessory APs are operating a legacy BSS; and

the wireless device transmits the ML configuration within a subfield of an ML element.

2. The wireless device of claim 1, wherein,

the ML configuration also indicates whether the legacy BSS of the one or more accessory APs is in the same ESS as the BSS of the wireless device or in a different ESS than the ESS of the BSS of the wireless device.

3. The wireless device of claim 1 or 2, wherein,

the first value of the subfield indicates that the one or more accessory APs are operating a legacy BSS in the same ESS as the wireless device;

the second value of the subfield indicates that the one or more accessory APs are operating a legacy BSS in an ESS different from the ESS of the wireless device; and is also provided with

The third value of the subfield indicates that the one or more accessory APs are not operating a legacy BSS.

4. The wireless device of any of claims 1-3, wherein the wireless device is further configured to:

The transmission of the group addressing frame is suppressed when one or more accessory APs are operating a legacy BSS in the same ESS as the wireless device.

5. The wireless device of any of claims 1-4, wherein the wireless device is further configured to:

transmitting a group key according to the value of the subfield.

6. A wireless device for receiving a multi-link ML configuration, wherein the wireless device corresponds to one or more dependent STAs, the wireless device configured to:

the wireless device receives the ML configuration, wherein the ML configuration indicates whether one or more accessory APs are operating a legacy BSS, wherein the ML configuration is carried on subfields of ML elements; and

the wireless device performs interactions with other wireless devices based on the ML configuration.

7. The wireless device of claim 6, wherein,

8. The wireless device of claim 6 or 7, wherein,

9. The wireless device of any of claims 6-8, wherein the wireless device is further configured to:

a group key is received based on the value of the subfield.

10. A method performed by a wireless device for transmitting a multilink ML configuration, wherein the wireless device corresponds to one or more accessory APs, the method comprising:

the wireless device obtains the ML configuration, wherein the ML configuration indicates whether one or more accessory APs are operating a legacy BSS; and

11. The method of claim 10, wherein,

12. The method according to claim 10 or 11, wherein,

The third value of the subfield indicates that the one or more accessory APs are not operating the legacy BSS.

13. The method of any of claims 10-12, further comprising:

14. The method of any of claims 10-13, further comprising:

transmitting a group key according to the value of the subfield.

15. A method performed by a wireless device that corresponds to one or more dependent STAs of receiving a multi-link ML configuration, the method comprising:

16. The method of claim 15, wherein,

17. The method according to claim 15 or 16, wherein,

18. The method of any of claims 15-17, further comprising:

a group key is received based on the value of the subfield.

19. A computer readable storage medium, wherein the computer readable storage medium stores a computer program which, when run on a computer, causes the computer to perform the method according to any one of claims 10 to 18.

20. A chip system comprising a processor configured to call a computer program from a memory and to run the computer program to cause a communication device on which the chip system is installed to perform the method according to any one of claims 10 to 18.