Method and apparatus for transmitting or receiving a protected control frame in a wireless LAN system

Abstract

A method and apparatus for transmitting or receiving a protected control frame in a wireless LAN system are disclosed. The method according to an embodiment of the present disclosure can include the steps of generating, by a first station (STA), a block acknowledgement (ACK) request frame based on an encryption protocol, and transmitting, by the first STA, the block ACK request frame to a second STA. In this case, the block ACK request frame includes encrypted information based on the encryption protocol, and the encrypted information can be based on a block ACK request control field or a block ACK request information field within a frame body of the block ACK request frame.

Description

Technical Field

[0001] This disclosure relates to a method and apparatus for transmitting or receiving protected control frames in a wireless local area network (WLAN) system. Background Technology

[0002] New technologies have been introduced for Wireless LANs (WLANs) to improve transmission rates, increase bandwidth, enhance reliability, reduce errors, and decrease latency. Within WLAN technology, the IEEE 802.11 series of standards can be referred to as Wi-Fi. For example, recent technologies introduced into WLAN include the Ultra High Throughput (VHT) enhancement of the 802.11 ac standard and the High Efficiency (HE) enhancement of the IEEE 802.11 ax standard.

[0003] To provide a more advanced wireless communication environment, improved techniques for Extremely High Throughput (EHT) are being discussed. For example, techniques for MIMO and multiple access point (AP) coordination that support increased bandwidth, efficient use of multiple frequency bands, and increased spatial flow are being investigated. Specifically, various techniques are being explored to support low latency or real-time traffic. Furthermore, new technologies to support Ultra-High Reliability (UHR), including improvements or extensions to EHT techniques, are being discussed. Summary of the Invention

[0004] Technical issues

[0005] The technical problem of this disclosure is to provide a method and apparatus for sending or receiving protected control frames in a WLAN system.

[0006] The technical problem of this disclosure is to provide a method and apparatus for supporting confidentiality and integrity in a WLAN system based on a counter mode protocol (CCMP) / Galois / counter mode protocol (GCMP) with cryptographic block chaining message authentication codes for block acknowledgment (ACK) request frames.

[0007] The technical objectives to be achieved by this disclosure are not limited to those described above, and other technical objectives not described herein will be clearly understood by those skilled in the art through the following description.

[0008] Technical solution

[0009] A method according to one aspect of this disclosure may include: a first station (STA) generating a block acknowledgment (ACK) request frame based on an encryption protocol; and the first STA sending the block ACK request frame to a second STA. Here, the block ACK request frame includes encrypted information based on the encryption protocol, and the encrypted information may be based on a block ACK request control field or a block ACK request information field within the frame body of the block ACK request frame.

[0010] The method according to an additional aspect of this disclosure may include: a second station (STA) receiving a block acknowledgment (ACK) request frame based on an encryption protocol from a first STA; and the second STA performing decryption and integrity verification on the block ACK request frame. Here, the block ACK request frame includes encrypted information based on the encryption protocol, and the encrypted information may be based on a block ACK request control field or a block ACK request information field within the frame body of the block ACK request frame.

[0011] Technical effect

[0012] According to this disclosure, based on the disclosure of a method for sending or receiving protected control frames in a WLAN system, a method and apparatus may be provided for supporting confidentiality and integrity in a WLAN system based on a counter mode protocol (CCMP) / Galois / counter mode protocol (GCMP) with cryptographic block chaining message authentication codes for block acknowledgment (ACK) request frames.

[0013] The effects achievable by this disclosure are not limited to those described above, and those skilled in the art can clearly understand other effects not described herein through the following description. Attached Figure Description

[0014] The accompanying drawings, which are included as part of the detailed description of this disclosure, provide embodiments of the disclosure and, together with the detailed description, describe the technical features of the disclosure.

[0015] Figure 1 A configuration block diagram of a wireless communication device according to an embodiment of the present disclosure is illustrated.

[0016] Figure 2 This is a diagram illustrating an exemplary structure of a WLAN system to which this disclosure can be applied.

[0017] Figure 3 This is a diagram used to illustrate the link establishment process that can be applied to this disclosure.

[0018] Figure 4 This is a diagram used to illustrate the backoff processing that can be applied to this disclosure.

[0019] Figure 5 This is a diagram illustrating the CSMA / CA-based frame transmission operation that can be applied to this disclosure.

[0020] Figure 6 This is a diagram illustrating an example of a frame structure that can be used in a WLAN system to which this disclosure may be applied.

[0021] Figure 7This is a diagram illustrating an example of a PPDU as defined in the IEEE 802.11 standard of this disclosure.

[0022] Figure 8 This is a diagram illustrating the four-way handshake process to which this disclosure can be applied.

[0023] Figure 9 This is a diagram illustrating an example of an extended CCMP MPDU that can be applied to this disclosure.

[0024] Figure 10 This indicates that the CCMP encapsulation block diagram disclosed herein can be applied.

[0025] Figure 11 An example of a regular AAD format.

[0026] Figure 12 This indicates that the CCMP decapsulation block diagram disclosed herein can be applied.

[0027] Figure 13 This is a diagram illustrating an example of an extended GCMP MPDU that can be applied to this disclosure.

[0028] Figure 14 This indicates that the GCMP encapsulation block diagram disclosed herein can be applied.

[0029] Figure 15 This indicates that the GCMP decapsulation block diagram disclosed herein can be applied.

[0030] Figure 16 This indicates an exemplary format for the block ACK request frame that can be applied according to this disclosure.

[0031] Figure 17 This is a diagram used to describe the operation of the first STA according to this disclosure.

[0032] Figure 18 This is a diagram used to describe the operation of the second STA according to this disclosure.

[0033] Figure 19 This represents an example of the MPDU format of the cryptographic protocol for block ACK request frames according to this disclosure.

[0034] Figure 20 This represents another example of the MPDU format of the encryption protocol for block ACK request frames according to this disclosure.

[0035] Figure 21 This represents another example of the MPDU format of the encryption protocol for block ACK request frames according to this disclosure.

[0036] Figure 22 This represents another example of the MPDU format of the encryption protocol for block ACK request frames according to this disclosure.

[0037] Figure 23 This represents another example of the MPDU format of the encryption protocol for block ACK request frames according to this disclosure.

[0038] Figure 24 This represents another example of the MPDU format of the encryption protocol for block ACK request frames according to this disclosure.

[0039] Figure 25 An example of a transmission STA operation supporting protection for a block ACK request frame, according to this disclosure, is illustrated.

[0040] Figure 26 The operation of a receiving STA supporting protection against block ACK request frames is illustrated according to this disclosure. Detailed Implementation

[0041] In the following, embodiments according to this disclosure will be described in detail with reference to the accompanying drawings. The detailed description disclosed with reference to the drawings is intended to describe exemplary embodiments of this disclosure and not to represent the only embodiments in which this disclosure can be implemented. The following detailed description includes specific details to provide a complete understanding of this disclosure. However, those skilled in the art will recognize that this disclosure can be implemented without these specific details.

[0042] In some cases, known structures and devices may be omitted, or they may be shown in block diagram form based on the core functions of each structure and device in order to prevent ambiguity in the concepts of this disclosure.

[0043] In this disclosure, when an element is referred to as “connected,” “combined,” or “linked” to another element, it can include both indirect and direct connections between the two elements. Furthermore, in this disclosure, the terms “comprising” or “having” specify the presence of the mentioned features, steps, operations, components, and / or elements, but do not exclude the presence or addition of one or more other features, stages, operations, components, elements, and / or groups thereof.

[0044] In this disclosure, terms such as "first" and "second" are used only to distinguish one element from another and are not used to limit the elements. Unless otherwise stated, they do not limit the order or importance of the elements. Therefore, within the scope of this disclosure, a first element in one embodiment may be referred to as a second element in another embodiment, and similarly, a second element in one embodiment may be referred to as a first element in another embodiment.

[0045] The terminology used in this disclosure is for the purpose of describing particular embodiments and not for limiting the claims. As used in the description of embodiments and the appended claims, the singular form is intended to include the plural form unless the context clearly indicates otherwise. The term “and / or” as used in this disclosure may refer to one of the associated enumerations, or is intended to refer to and include any and all possible combinations of two or more of them. Furthermore, unless otherwise stated, the “ / ” between words in this disclosure has the same meaning as “and / or”.

[0046] The examples disclosed herein can be applied to various wireless communication systems. For example, the examples disclosed herein can be applied to wireless LAN systems. For example, the examples disclosed herein can be applied to wireless LANs based on the IEEE 802.11a / g / n / ac / ax standards. Furthermore, the examples disclosed herein can be applied to wireless LANs based on the newly proposed IEEE 802.11be (or EHT) standard. The examples disclosed herein can be applied to wireless LANs based on the IEEE 802.11be version 2 standard, corresponding to the additional enhancements of the IEEE 802.11be version 1 standard. Additionally, the examples disclosed herein can be applied to wireless LANs based on next-generation standards after IEEE 802.11be. Furthermore, the examples disclosed herein can be applied to cellular wireless communication systems. For example, it can be applied to cellular wireless communication systems based on 3GPP standards using Long Term Evolution (LTE) technology and 5G New Radio (NR) technology.

[0047] The technical features that can be applied to examples of this disclosure will be described below.

[0048] Figure 1 A block diagram illustrating a wireless communication device according to an embodiment of the present disclosure is shown.

[0049] Figure 1 The first device 100 and the second device 200 illustrated herein can be replaced by various terms such as terminal, wireless device, wireless transceiver unit (WTRU), user equipment (UE), mobile station (MS), user terminal (UT), mobile subscriber station (MSS), mobile subscriber unit (MSU), subscriber station (SS), advanced mobile station (AMS), wireless terminal (WT), or simply user. Furthermore, the first device 100 and the second device 200 include access point (AP), base station (BS), fixed station, node B, base transceiver system (BTS), and network. It can be replaced by various terms such as artificial intelligence (AI) system, roadside unit (RSU), repeater, router, relay, and gateway.

[0050] Figure 1The devices 100 and 200 illustrated herein may be referred to as stations (STAs). For example, Figure 1 The devices 100 and 200 illustrated herein may be referred to by various terms such as transmitting device, receiving device, transmitting STA, and receiving STA. For example, STA 110 and 200 may perform an access point (AP) role or a non-AP role. That is, in this disclosure, STA 110 and 200 may perform AP and / or non-AP functions. When STA 110 and 200 perform AP functions, they may simply be referred to as APs, and when STA 110 and 200 perform non-AP functions, they may simply be referred to as STAs. Alternatively, in this disclosure, AP may also be referred to as AP STA.

[0051] Reference Figure 1 The first device 100 and the second device 200 can transmit and receive radio signals via various wireless LAN technologies (e.g., IEEE 802.11 series). The first device 100 and the second device 200 may include interfaces for the Media Access Control (MAC) layer and Physical Layer (PHY) conforming to the IEEE 802.11 standard.

[0052] In addition to wireless LAN technology, the first device 100 and the second device 200 can also support various communication standards (e.g., 3GPP LTE series, 5G NR series standards, etc.). Furthermore, the devices disclosed herein can be implemented in various devices such as mobile phones, vehicles, personal computers, augmented reality (AR) devices, and virtual reality (VR) devices. Additionally, the STA of this specification can support various communication services such as voice calls, video calls, data communication, autonomous driving, machine-type communication (MTC), machine-to-machine (M2M), device-to-device (D2D), and IoT (Internet of Things).

[0053] The first device 100 may include one or more processors 102 and one or more memories 104, and may additionally include one or more transceivers 106 and / or one or more antennas 108. The processors 102 may control the memories 104 and / or the transceivers 106, and may be configured to implement the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts included in this disclosure. For example, the processor 102 may transmit a wireless signal including the first information / signal via the transceivers 106 after generating first information / signal by processing information in the memories 104. Additionally, the processor 102 may receive a wireless signal including second information / signal via the transceivers 106, and then store information obtained through signal processing of the second information / signal in the memories 104. The memories 104 may be connected to the processor 102 and may store various information related to the operation of the processor 102. For example, the memories 104 may store software code including instructions for performing all or part of the processing controlled by the processor 102 or for performing the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts included in this disclosure. Here, processor 102 and memory 104 may be part of a communication modem / circuit / chip designed to implement wireless LAN technology (e.g., IEEE 802.11 series). Transceiver 106 may be connected to processor 102 and may transmit and / or receive wireless signals via one or more antennas 108. Transceiver 106 may include a transmitter and / or a receiver. Transceiver 106 may be used with an RF (radio frequency) unit. In this disclosure, wireless device may refer to a communication modem / circuit / chip.

[0054] The second device 200 may include one or more processors 202 and one or more memories 204, and may additionally include one or more transceivers 206 and / or one or more antennas 208. The processors 202 may control the memories 204 and / or the transceivers 206, and may be configured to implement the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts included in this disclosure. For example, the processors 202 may generate third information / signals by processing information in the memories 204, and then transmit a wireless signal including the third information / signals via the transceivers 206. Additionally, the processors 202 may receive wireless signals including fourth information / signals via the transceivers 206, and then store information obtained through signal processing of the fourth information / signals in the memories 204. The memories 204 may be connected to the processors 202 and may store various information related to the operation of the processors 202. For example, the memories 204 may store software code including instructions for performing all or part of the processing controlled by the processors 202 or for performing the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts included in this disclosure. Here, processor 202 and memory 204 may be part of a communication modem / circuit / chip designed to implement wireless LAN technology (e.g., IEEE 802.11 series). Transceiver 206 may be connected to processor 202 and may transmit and / or receive wireless signals via one or more antennas 208. Transceiver 206 may include a transmitter and / or a receiver. Transceiver 206 may be used with an RF unit. In this disclosure, apparatus may refer to a communication modem / circuit / chip.

[0055] The hardware elements of devices 100 and 200 will be described in more detail below. Not limited thereto, one or more protocol layers may be implemented by one or more processors 102 and 202. For example, one or more processors 102 and 202 may implement one or more layers (e.g., functional layers such as PHY and MAC). One or more processors 102 and 202 may generate one or more PDUs (Protocol Data Units) and / or one or more SDUs (Service Data Units) according to the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts disclosed in this disclosure. One or more processors 102 and 202 may generate messages, control information, data, or information according to the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts disclosed in this disclosure. One or more processors 102 and 202 may generate signals (e.g., baseband signals) including PDUs, SDUs, messages, control information, data, or information according to the functions, processes, suggestions, and / or methods disclosed in this disclosure to provide them to one or more transceivers 106 and 206. One or more processors 102, 202 may receive signals (e.g., baseband signals) from one or more transceivers 106, 206 and obtain PDUs, SDUs, messages, control information, data or information, in accordance with the description, functions, processes, suggestions, methods and / or operation flowcharts included in this disclosure.

[0056] One or more processors 102, 202 may be referred to as controllers, microcontrollers, microprocessors, or microcomputers. One or more processors 102, 202 may be implemented by hardware, firmware, software, or a combination thereof. For example, one or more ASICs (Application-Specific Integrated Circuits), one or more DSPs (Digital Signal Processors), one or more DSPDs (Digital Signal Processing Devices), one or more PLDs (Programmable Logic Devices), or one or more FPGAs (Field-Programmable Gate Arrays) may be included in one or more processors 102, 202. The descriptions, functions, processes, suggestions, methods, and / or operation flowcharts included in this disclosure may be implemented using firmware or software, and the firmware or software may be implemented to include modules, processes, functions, etc. Firmware or software configured to execute the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts included in this disclosure may be included in one or more processors 102, 202, or may be stored in one or more memories 104, 204 and driven by one or more processors 102, 202. The descriptions, functions, processes, suggestions, methods and / or operation flowcharts included in this disclosure may be implemented using firmware or software in the form of code, instructions and / or instruction sets.

[0057] One or more memories 104, 204 may be connected to one or more processors 102, 202 and may store data, signals, messages, information, programs, code, instructions, and / or commands in various forms. One or more memories 104, 204 may be configured with ROM, RAM, EPROM, flash memory, hard disk drive, registers, cache memory, computer-readable storage media, and / or combinations thereof. One or more memories 104, 204 may be located internally and / or externally to one or more processors 102, 202. Furthermore, one or more memories 104, 204 may be connected to one or more processors 102, 202 via various technologies such as wired or wireless connections.

[0058] One or more transceivers 106, 206 can transmit user data, control information, wireless signals / channels, etc., mentioned in the methods and / or operation flowcharts of this disclosure to one or more other devices. One or more transceivers 106, 206 can receive user data, control information, wireless signals / channels, etc., mentioned in the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts included in this disclosure from one or more other devices. For example, one or more transceivers 106, 206 can be connected to one or more processors 102, 202 and can transmit and receive wireless signals. For example, one or more processors 102, 202 can control one or more transceivers 106, 206 to transmit user data, control information, or wireless signals to one or more other devices. Additionally, one or more processors 102, 202 can control one or more transceivers 106, 206 to receive user data, control information, or wireless signals from one or more other devices. Additionally, one or more transceivers 106, 206 may be connected to one or more antennas 108, 208, and one or more transceivers 106, 206 may be configured to transmit and receive user data, control information, wireless signals / channels, etc., mentioned in the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts included in this disclosure, via one or more antennas 108, 208. In this disclosure, one or more antennas may be multiple physical antennas or multiple logical antennas (e.g., antenna ports). One or more transceivers 106, 206 may convert received wireless signals / channels, etc., from RF band signals into baseband signals for processing using one or more processors 102, 202. One or more transceivers 106, 206 may convert user data, control information, wireless signals / channels, etc., processed using one or more processors 102, 202, from baseband signals into RF band signals. Therefore, one or more transceivers 106, 206 may include (analog) oscillators and / or filters.

[0059] For example, one of STAs 100 and 200 can perform the expected operation of an AP, and the other of STAs 100 and 200 can perform the expected operation of a non-AP STA. For example, Figure 1 Transceivers 106 and 206 can perform transmission and reception operations of signals (e.g., packet or physical layer protocol data units (PPDUs) conforming to IEEE 802.11a / b / g / n / ac / ax / be / bn). Additionally, in this disclosure, the various STAs can generate transmit / receive signals or perform data processing or calculations on the transmit / receive signals in advance by [the relevant entity / component]. Figure 1Processors 102 and 202 perform the following operations: For example, examples of generating transmit / receive signals or performing data processing or computations on transmit / receive signals in advance may include: 1) determining / acquiring / configuring / computing / decoding / encoding bit information of fields (signals (SIG), short training field (STF), long training field (LTF), data, etc.) included in the PPDU; 2) determining / configuring / acquiring time or frequency resources (e.g., subcarrier resources) for the fields (SIG, STF, LTF, data, etc.) included in the PPDU; 3) determining / configuring / acquiring specific sequences (e.g., pilot sequences, STF / LTF sequences, additional sequences applied to SIG) for the fields (SIG, STF, LTF, data, etc.) included in the PPDU action; 4) power control operations and / or power saving operations applied to the STA; 5) operations related to determining / acquiring / configuring / computing / decoding / encoding of the ACK signal. Additionally, in the example below, various information used by different STAs to determine / acquire / configure / calculate / decode / encode transmitted and received signals (e.g., information related to fields / subfields / control fields / parameters / power, etc.) can be stored. Figure 1 In memory 104 and 204.

[0060] In the following text, downlink (DL) can refer to a link used for communication from an AP STA to a non-AP STA, and DL PPDU / packets / signals can be sent and received via DL. In DL communication, the transmitter can be part of an AP STA, and the receiver can be part of a non-AP STA. Uplink (UL) can refer to a link used for communication from a non-AP STA to an AP STA, and UL PPDU / packets / signals can be sent and received via UL. In UL communication, the transmitter can be part of a non-AP STA, and the receiver can be part of an AP STA.

[0061] Figure 2 This is a diagram illustrating an exemplary structure of a wireless LAN system to which this disclosure can be applied.

[0062] A wireless LAN system can be structured by multiple components. These components interact to provide STA mobility support that is transparent to upper layers. The Basic Service Set (BSS) corresponds to the basic building blocks of a wireless LAN. Figure 2 An example is shown where there are two BSSs (BSS1 and BSS2), and two STAs included as members of each BSS (STA1 and STA2 are included in BSS1, and STA3 and STA4 are included in BSS2). Figure 2The ellipse representing the BSS can also be interpreted as representing the coverage area within the corresponding BSS where STAs maintain communication. This area can be called the Basic Service Area (BSA). When a STA moves outside the BSA, it cannot communicate directly with other STAs within the BSA.

[0063] If we do not consider Figure 2 The DS shown in the diagram represents the most basic BSS type in a wireless LAN: the Independent BSS (IBSS). For example, an IBSS can have a minimal form containing only two STAs. For instance, assuming other components are omitted, BSS1 containing only STA1 and STA2, or BSS2 containing only STA3 and STA4, can respectively correspond to representative examples of IBSS. This configuration is possible when STAs can communicate directly without an AP. Furthermore, in this type of wireless LAN, it is not pre-configured but can be configured as needed, and this can be called an ad-hoc network. Since an IBSS does not include an AP, there is no centralized management entity. That is, in an IBSS, STAs are managed in a distributed manner. In an IBSS, all STAs can consist of mobile STAs and are not allowed to access the Distributed System (DS), thus forming a self-contained network.

[0064] Membership of an STA in a BSS can be dynamically changed by opening or closing an STA, or by entering or leaving a BSS zone. To become a member of a BSS, an STA can join the BSS using a synchronization process. To access all services of the BSS infrastructure, an STA must be associated with the BSS. This association can be dynamically established and may include the use of Distributed System Services (DSS).

[0065] Direct STA-to-STA distance in a wireless LAN may be limited by PHY performance. In some cases, this distance limitation may be sufficient, but in others, longer distances between STAs may be required for communication. Distributed systems (DS) can be configured to support extended coverage.

[0066] DS refers to the structure of BSS interconnection. Specifically, such as... Figure 2As shown, a BSS can exist as an extension of a network composed of multiple BSSs. A DS is a logical concept and can be specified through the characteristics of the Distributed System Medium (DSM). At this point, the Wireless Medium (WM) and the DSM can be logically separated. Each logical medium is used for a different purpose and by different components. These media are not limited to being the same, nor are they limited to being different. In this way, the flexibility of a wireless LAN architecture (DS architecture or other network architectures) can be interpreted as multiple media being logically different. That is, a wireless LAN architecture can be implemented in various ways, and the corresponding wireless LAN architecture can be independently specified by the physical characteristics of each implementation.

[0067] The DS can support mobile devices by providing seamless integration of multiple BSSs and offering the logical services necessary for addressing to the destination. Additionally, the DS may include a component called a portal, which acts as a bridge between the wireless LAN and other networks, such as IEEE 802.X.

[0068] AP enables access to DS via WM for associated non-AP STAs, and refers to entities that also have STA functionality. Data movement between BSS and DS can be performed through AP. For example, Figure 2 STA2 and STA3, shown in the diagram, have the functionality of STAs and provide the ability for associated non-AP STAs (STA1 and STA4) to access the DS. Furthermore, since all APs essentially correspond to STAs, all APs are addressable entities. The address used by an AP for communication on the WM is not necessarily the same as the address used by the AP for communication on the DSM. A BSS consisting of APs and one or more STAs can be referred to as an infrastructure BSS.

[0069] Data sent from one of the STAs associated with the AP to the corresponding STA address of the AP can always be received on an uncontrolled port and can be processed by the IEEE 802.1X port access entity. Alternatively, when the controlled port is authenticated, the transmitted data (or frames) can be delivered to the DS.

[0070] In addition to the DS structure described above, Extended Service Sets (ESS) can also be configured to provide wide coverage.

[0071] An ESS (Service Set Identity) refers to a network of arbitrary size and complexity consisting of DS (Service Controller) and BSS (Service Set Service). An ESS can correspond to a set of BSSs connected to a DS. However, an ESS does not include the DS. An ESS network is characterized as an IBSS (Integrated Service Set Service) within the Logical Link Control (LLC) layer. STAs included in an ESS can communicate with each other, and a moving STA can transparently move from one BSS to another (within the same ESS) to the LLC. APs included in an ESS can have the same Service Set Identity (SSID). The SSID is distinguished from the BSSID, which serves as the identifier for the BSS.

[0072] Wireless LAN systems make no assumptions about the relative physical locations of BSSs, and all of the following forms are possible. BSSs can partially overlap, a form commonly used to provide continuous coverage. Additionally, BSSs may not be physically connected, and logically, there is no limit to the distance between BSSs. Furthermore, BSSs can be physically located in the same location, which can be used to provide redundancy. Additionally, one (or more) IBSS or ESS networks can physically exist in the same space as one (or more) ESS networks. This can correspond to the form of ESS networks when an ad hoc network operates in a location where an ESS network exists, when physically overlapping wireless networks are configured by different organizations, or when two or more different access and security policies are required in the same location, etc.

[0073] Figure 3 This is a diagram illustrating the link establishment process that can be applied to this disclosure.

[0074] In order for a STA to establish a link with the network and send / receive data, it first discovers the network, performs authentication, establishes an association, and performs authentication processing for security. The link establishment process can also be called session initiation processing or session establishment processing. Furthermore, the discovery, authentication, association, and security establishment processes of the link establishment process can be collectively referred to as association processing.

[0075] In step S310, the STA can perform a network discovery operation. The network discovery operation may include a scanning operation by the STA. That is, in order for the STA to access a network, it needs to find networks it can participate in. The STA should identify compatible networks before participating in a wireless network, and the process of identifying networks existing in a specific area is called scanning.

[0076] Scanning schemes include active scanning and passive scanning. Figure 3An exemplary network discovery operation including active scanning processing is illustrated. In active scanning, the STA performing the scan sends a probe request frame to discover which APs are present around it as the channel moves and awaits a response. The responder sends a probe response frame as a response to the probe request frame to the STA that sent the probe request frame. Here, the responder may be the STA that last sent a beacon frame in the BSS of the channel being scanned. In the BSS, the AP becomes the responder because it sends a beacon frame, and in the IBSS, the STAs in the IBSS rotate to send beacon frames, so the responder is not constant. For example, an STA that sends a probe request frame on channel 1 and receives a probe response frame on channel 1 may store the BSS-related information included in the received probe response frame and may move to the next channel (e.g., channel 2) and perform a scan in the same manner (i.e., sending and receiving probe requests / responses on channel 2).

[0077] Although not in Figure 3 As shown, scanning can be performed passively. In passive scanning, the STA performing the scan waits for beacon frames while moving through the channel. Beacon frames are one of the management frames defined in IEEE 802.11 and are sent periodically to notify of the existence of a wireless network and allow the STA performing the scan to find and participate in the wireless network. In the BSS, the AP periodically sends beacon frames, and in the IBSS, the STA within the IBSS rotates to send beacon frames. When the STA performing the scan receives a beacon frame, it stores the BSS information included in the beacon frame and records the beacon frame information for each channel while moving to another channel. The STA receiving the beacon frame can store the BSS-related information included in the received beacon frame, move to the next channel, and perform scanning in the next channel in the same manner. Comparing active and passive scanning, active scanning has the advantages of less latency and less power consumption.

[0078] After the STA discovers the network, an authentication process can be performed in step S320. To clearly distinguish it from the security establishment operation in step S340, which will be described later, this authentication process can be referred to as the first authentication process.

[0079] The authentication process includes the following steps: the STA sends an authentication request frame to the AP, and in response, the AP sends an authentication response frame to the STA. The authentication frame used for the authentication request / response corresponds to the management frame.

[0080] An authentication frame includes the authentication algorithm number, authentication transaction sequence number, status code, challenge text, robust security network (RSN), and finite circular group. These correspond to some examples of information that can be included in the authentication request / response frame and can be replaced with other information, or additional information may be included.

[0081] A STA can send an authentication request frame to an AP. The AP can determine whether to allow the corresponding STA's authentication based on the information included in the received authentication request frame. The AP can then provide the STA with the authentication processing result via an authentication response frame.

[0082] After the STA is successfully authenticated, the association process can be performed in step S330. The association process includes the following steps: the STA sends an association request frame to the AP, and in response, the AP sends an association response frame to the STA.

[0083] For example, an association request frame may include information related to various capabilities, beacon listening intervals, service set identifiers (SSIDs), supported rates, supported channels, RSNs, mobility domains, supported operation classes, traffic indication mapping broadcast requests (TIM broadcast requests), interoperability capabilities, etc. Similarly, an association response frame may include information related to various capabilities, status codes, association IDs (AIDs), supported rates, enhanced distributed channel access (EDCA) parameter sets, received channel power indicators (RCPIs), received signal-to-noise ratio indicators (RSNIs), mobility domains, timeout intervals (e.g., association recovery time), overlapping BSS scan parameters, TIM broadcast responses, quality of service (QoS) mappings, etc. These correspond to some examples of information that can be included in association request / response frames and may be replaced with other information, or additional information may be included.

[0084] After the STA successfully associates with the network, a security establishment process can be performed in step S340. The security establishment process in step S340 can be referred to as the authentication process via a Robust Secure Network Association (RSNA) request / response, the authentication process in step S320 is referred to as the first authentication process, and the security establishment process in step S340 can also be simply referred to as the authentication process.

[0085] The secure establishment process in step S340 may include, for example, the process of establishing a private key using a four-way handshake via Extensible Authentication Protocol (EAPOL) frames over the LAN. Alternatively, the secure establishment process may be performed according to a security scheme not defined in the IEEE 802.11 standard.

[0086] Figure 4 This is a diagram illustrating the fallback process that can be applied to this disclosure.

[0087] In wireless LAN systems, the basic access mechanism for Media Access Control (MAC) is Carrier Sensing Multiple Access with Collision Avoidance (CSMA / CA). Also known as the Distributed Coordination Function (DCF) of IEEE 802.11 MAC, CSMA / CA essentially employs a "listen-before-talk" access mechanism. Under this type of access mechanism, before commencing transmission, the AP and / or STA can perform explicit channel assessment (CCA) of the sensing radio channel or medium during a predetermined time interval (e.g., the DCF inter-frame interval (DIFS)). As a result of the sensing, if it is determined that the medium is idle, frame transmission begins via the corresponding medium. Conversely, if the medium is detected to be occupied or busy, the corresponding AP and / or STA does not begin its own transmission and can set a delay period for medium access (e.g., a random backoff period) and attempt frame transmission after waiting. By applying a random backoff period, collisions can be minimized because multiple STAs are expected to attempt frame transmission after waiting for different time periods.

[0088] In addition, the IEEE 802.11 MAC protocol provides a Hybrid Coordination Function (HCF). HCF is based on DCF and Point Coordination Function (PCF). PCF is a polling-based synchronous access method, meaning that all receiving APs and / or STAs periodically poll to receive data frames. Furthermore, HCF includes Enhanced Distributed Channel Access (EDCA) and HCF Control Channel Access (HCCA). EDCA is a contention-based access method that provides data frames to multiple users, while HCCA uses a non-contention-based channel access method that utilizes a polling mechanism. Additionally, HCF includes a media access mechanism for improving the QoS (Quality of Service) of wireless LANs and can transmit QoS data during contention periods (CP) and contention-free periods (CFP).

[0089] Reference Figure 4This section describes the operation based on a random backoff period. When an occupied / busy medium becomes idle, multiple STAs can attempt to transmit data (or frames). As a method to minimize collisions, each STA can individually select a random backoff count and attempt to transmit after waiting for the corresponding time slot. The random backoff count has a pseudo-random integer value and can be determined as one of the values ​​ranging from 0 to CW. Here, CW is the contention window parameter value. The CW parameter is assigned an initial value of CWmin, but can take a value twice as large as in the event of transmission failure (e.g., when no ACK is received for the transmitted frame). When the CW parameter value reaches CWmax, data transmission can be attempted while maintaining the CWmax value until successful data transmission, and when successful, the CWmin value is reset. The values ​​of CW, CWmin, and CWmax are preferably set to 2n-1 (n=0, 1, 2, ...).

[0090] When random backoff processing begins, the STA continuously monitors the medium during the backoff time slot countdown based on the determined backoff count value. When monitoring the medium for occupancy, it stops the countdown and waits, and restarts the remainder of the countdown when the medium becomes idle.

[0091] exist Figure 4 In the example, when the packet to be sent arrives at STA 3's MAC, STA 3 can send the frame immediately after confirming that the medium has been idle for up to DIFS. The remaining STAs monitor and wait for the medium to be occupied / busy. Meanwhile, the data to be sent can also occur in each of STA 1, STA 2, and STA 5, and when the medium is detected as idle, each STA waits for up to DIFS, and then performs a countdown for the backoff slot based on a random backoff count value chosen by each STA. Assume STA 2 chooses the minimum backoff count value, and STA 1 chooses the maximum backoff count value. That is, the example illustrates the case where STA 5's remaining backoff time is shorter than STA 1's remaining backoff time when STA 2 completes its backoff count and begins frame transmission. STA 1 and STA 5 temporarily stop the countdown and wait while STA 2 occupies the medium. When STA 2's occupancy ends and the medium becomes idle again, STA 1 and STA 5 wait for DIFS and restart the stopped backoff count. In other words, frame transmission can begin after a countdown for the remaining backoff slot based on the remaining backoff time. Since STA5 has a shorter remaining backoff time than STA1, STA5 begins frame transmission. Data to be transmitted can also occur in STA4 while STA2 is occupying the medium. From STA4's perspective, when the medium becomes idle, STA4 can wait for DIFS, then execute a countdown based on a random backoff count value selected by STA4, and begin transmitting frames. Figure 4The example illustrates a scenario where the remaining backoff time of STA5 accidentally conflicts with the random backoff count value of STA4. In this case, a collision may occur between STA4 and STA5. When a collision occurs, neither STA4 nor STA5 receives an ACK, so data transmission fails. In this situation, STA4 and STA5 can double the CW value, select a random backoff count value, and begin a countdown. While the medium is occupied due to the transmissions of STA4 and STA5, STA1 waits; when the medium becomes idle, STA1 waits for DIFS, and then begins frame transmission after the remaining backoff time has elapsed.

[0092] As in Figure 4 In the example, data frames are frames used to send data forwarded to higher layers and can be sent after a backoff performed after DIFS, starting from when the medium becomes idle. Additionally, management frames are frames used to exchange management information that has not been forwarded to higher layers and are sent after a backoff performed after an IFS such as DIFS or Point Coordination Function IFS (PIFS). Subtypes of management frames include beacons, association requests / responses, reassociation requests / responses, probe requests / responses, authentication requests / responses, etc. Control frames are frames used to control access to the medium. Subtypes of control frames include request to send (RTS), clear send (CTS), acknowledge (ACK), power-saving polling (PS-Poll), block ACK (BlockAck), block ACK request (BlockACKReq), empty data packet advertisement (NDP advertisement), and triggers, etc. If a control frame is not a response frame to the previous frame, it is sent after a backoff performed after DIFS; if it is a response frame to the previous frame, it is sent without a backoff performed after short IFS (SIFS). The type and subtype of a frame can be identified by the type field and subtype field in the Frame Control (FC) field.

[0093] The Quality of Service (QoS) ST can perform a backoff following the Arbitration IFS (AIFS) for the Access Class (AC) to which the frame belongs (i.e., AIFS where i is a value determined by the AC) before the frame can be transmitted. Here, the frame that can use AIFS can be a data frame, management frame, or control frame, rather than a response frame.

[0094] Figure 5 This is a diagram illustrating the CSMA / CA-based frame transmission operation that can be applied to this disclosure.

[0095] As mentioned above, in addition to physical carrier sensing of the medium directly sensed by the STA, the CSMA / CA mechanism also includes virtual carrier sensing. Virtual carrier sensing aims to compensate for problems such as hidden node issues that may occur during medium access. For virtual carrier sensing, the STA's MAC can use the Network Allocation Vector (NAV). The NAV is a value that indicates to other STAs the remaining time until the medium is available for current use or for STAs authorized to use the medium. Therefore, a value set to NAV corresponds to the period during which the STA sending the frame plans to use the medium, and during the corresponding period, STAs receiving the NAV value are prohibited from accessing the medium. For example, the NAV can be configured based on the value of the "Duration" field in the frame's MAC header.

[0096] exist Figure 5 In the example, it is assumed that STA1 intends to send data to STA2, and STA3 is in a position that can eavesdrop on some or all of the frames sent and received between STA1 and STA2.

[0097] To reduce the likelihood of transmission conflicts among multiple STAs in CSMA / CA-based frame transmission operations, a mechanism using RTS / CTS frames can be applied. Figure 5 In the example, when STA1 is transmitting, as a result of carrier sensing by STA3, it can be determined that the medium is in an idle state. That is, STA1 can correspond to a hidden node with respect to STA3. Alternatively, in Figure 5 In the example, it can be determined that while STA2 is transmitting, the carrier sensing result medium of STA3 is in an idle state. That is, STA2 can correspond to a hidden node with respect to STA3. By exchanging RTS / CTS frames before performing data transmission and reception between STA1 and STA2, STAs outside the transmission range of either STA1 or STA2, or STAs outside the carrier sensing range of transmissions from STA1 or STA3, can avoid attempting to occupy the channel during data transmission and reception between STA1 and STA2.

[0098] Specifically, STA1 can determine whether a channel is in use through carrier sensing. Regarding physical carrier sensing, STA1 can determine the channel occupancy / idle status based on the energy level or signal correlation detected in the channel. Alternatively, regarding virtual carrier sensing, STA1 can use a Network Allocation Vector (NAV) timer to determine the channel occupancy status.

[0099] When the channel is idle during DIFS, STA1 can send an RTS frame to STA2 after performing backoff. When STA2 receives the RTS frame, STA2 can send a CTS frame to STA1 after SIFS as a response to the RTS frame.

[0100] If STA3 cannot eavesdrop on CTS frames from STA2 but can eavesdrop on RTS frames from STA1, STA3 can use the duration information included in the RTS frame to set the NAV timer for the subsequent consecutive frame transmission period (e.g., SIFS+CTS frame+SIFS+data frame+SIFS+ACK frame). Alternatively, if STA3 can eavesdrop on CTS frames from STA2, STA3 can also use the duration information included in the CTS frame to set the NAV timer for the subsequent consecutive frame transmission period (e.g., SIFS+data frame+SIFS+ACK frame) even though STA3 cannot eavesdrop on RTS frames from STA1. That is, if STA3 can eavesdrop on one or more RTS frames or CTS frames from STA1 or STA2, STA3 can set the NAV accordingly. When STA3 receives a new frame before the NAV timer expires, STA3 can update the NAV timer using the duration information included in the new frame. STA3 does not attempt channel access until the NAV timer expires.

[0101] When STA1 receives a CTS frame from STA2, STA1 can send a data frame to STA2 after SIFS, starting from the time point when the CTS frame reception is complete. When STA2 successfully receives the data frame, STA2 can send an ACK frame to STA1 after SIFS as a response to the data frame. When the NAV timer expires, STA3 can determine whether the channel is in use through carrier sensing. If STA3 determines that the channel is not in use by other terminals during DIFS after the NAV timer expires, STA3 can attempt channel access after the contention window (CW) for random backoff has passed.

[0102] Figure 6 This is a diagram illustrating an example of a frame structure that can be used in a WLAN system to which this disclosure may be applied.

[0103] Using instructions or primitives (meaning a set of instructions or parameters) from the MAC layer, the PHY layer can prepare the MAC PDU (MPDU) to be transmitted. For example, when the PHY layer receives a command from the MAC layer requesting the start of transmission, it switches to transmit mode, configures the information (e.g., data) provided by the MAC layer in the form of a frame, and transmits it. Additionally, when the PHY layer detects a valid preamble in a received frame, it monitors the preamble header and sends a command to the MAC layer notifying the PHY layer of the start of reception.

[0104] In this way, information transmission / reception in a wireless LAN system is performed in the form of frames, and for this purpose, the PHY layer Protocol Data Unit (PPDU) format is defined.

[0105] A basic PPDU can include a Short Training Field (STF), a Long Training Field (LTF), a Signal (SIG) field, and a Data field. The most basic PPDU format (e.g., Figure 7 The non-HT (High Throughput) fields shown can consist solely of a Traditional-STF (L-STF), Traditional-LTF (L-LTF), Traditional-SIG (L-SIG) field, and a data field. Additionally, depending on the PPDU format type (e.g., HT mixed format PPDU, HT green format PPDU, VHT (Very High Throughput) PPDU, etc.), additional (or different types) RL-SIG, U-SIG, non-traditional SIG fields, non-traditional STF, non-traditional LTF (i.e., xx-SIG, xx-STF, xx-LTF (e.g., xx is HT, VHT, HE, EHT, etc.)) can be included between the L-SIG field and the data field.

[0106] STF is a signal used for signal detection, automatic gain control (AGC), diversity selection, precise time synchronization, etc., while LTF is a signal used for channel estimation and frequency error estimation. STF and LTF can be referred to as signals used for synchronization and channel estimation in the OFDM physical layer.

[0107] The SIG field can include various information related to PPDU transmission and reception. For example, the L-SIG field consists of 24 bits and can include a 4-bit rate field, a 1-bit reserved bit, a 12-bit length field, a 1-bit parity field, and a 6-bit tail field. The RATE field can include information about the modulation and coding rate of the data. For example, the 12-bit length field can include information about the length or duration of the PPDU. For example, the value of the 12-bit length field can be determined based on the type of PPDU. For example, for non-HT, HT, VHT, or EHT PPDUs, the value of the length field can be determined to be a multiple of 3. For example, for HE PPDUs, the value of the length field can be determined to be a multiple of 3+1 or 3+2.

[0108] The data field may include a service field, a physical layer service data unit (PSDU), and PPDU tail bits, and may also include padding bits if necessary. Some bits of the service field can be used for synchronization of the descrambler at the receiver. The PSDU corresponds to the MAC PDU defined in the MAC layer and may include data generated / used in the upper layer. The PPDU tail bits can be used to return the encoder to a 0 state. Padding bits can be used to adjust the length of the data field by predetermined units.

[0109] MAC PDUs are defined according to various MAC frame formats, and a basic MAC frame consists of a MAC header, a frame body, and a Frame Check Sequence (FCS). MAC frames can be composed of MAC PDUs and transmitted / received via PSDUs in the data portion of the PPDU format.

[0110] The MAC header includes a frame control field, a duration / ID field, and an address field. The frame control field can include control information required for frame transmission / reception. The duration / ID field can be set to the time used to transmit the corresponding frame, etc. For details on the sequence control, QoS control, and HT control subfields of the MAC header, refer to the IEEE 802.11 standard document.

[0111] The Narrow Data PPDU (NDP) format refers to a PPDU format that does not include the data field. In other words, NDP is a frame format that includes the PPDU preamble of the general PPDU format (i.e., the L-STF, L-LTF, L-SIG fields and other non-traditional SIG, non-traditional STF, and non-traditional LTF (if present)) and does not include the remaining part (i.e., the data field).

[0112] Figure 7 This is a diagram illustrating an example of a PPDU as defined in the IEEE 802.11 standard of this disclosure.

[0113] Various types of PPDUs have been used in standards such as IEEE 802.11a / g / n / ac / ax. The basic PPDU format (IEEE 802.11a / g) includes L-LTF, L-STF, L-SIG, and a data field. The basic PPDU format can also be referred to as a non-HT PPDU format (such as...). Figure 7 (as shown in (a)).

[0114] Compared to the basic PPDU format, the HT PPDU format (IEEE 802.11n) additionally includes the HT-SIG, HT-STF, and HT-LFT fields. Figure 7The HT PPDU format shown in (b) can be referred to as the HT hybrid format. Furthermore, an HT green format PPDU can be defined, and this corresponds to a format consisting of HT-GF-STF, HT-LTF1, HT-SIG, one or more HT-LTFs and data fields, excluding L-STF, L-LTF, and L-SIG (not shown).

[0115] Compared to the basic PPDU format, examples of the VHT PPDU format (IEEE 802.11ac) additionally include VHTSIG-A, VHT-STF, VHT-LTF, and VHT-SIG-B fields (such as...). Figure 7 (as shown in (c)).

[0116] Compared to the basic PPDU format, examples of the HE PPDU format (IEEE 802.11ax) additionally include repeated L-SIG (RL-SIG), HE-SIG-A, HE-SIG-B, HE-STF, HE-LTF, and Packet Extension (PE) fields (such as...). Figure 7 (as shown in (d)). Some fields can be excluded, or their lengths can vary depending on the detailed examples of the HE PPDU format. For example, the HE-SIG-B field is included in the HE PPDU format for multi-user (MU), but not in the HE PPDU format for single-user (SU). Furthermore, the HE-Trigger-Based (TB) PPDU format does not include HE-SIG-B, and the length of the HE-STF field can vary up to 8 μs. The Extended Range (HE ER) SU PPDU format does not include the HE-SIG-B field, and the length of the HE-SIG-A field can vary up to 16 μs. For example, RL-SIG can be configured to be the same as L-SIG. Based on the presence of RL-SIG, the receiving STA can determine whether the received PPDU is an HE PPDU or an EHT PPDU, which will be described later.

[0117] EHT PPDU format can include Figure 7 EHT MU (Multi-user) in (e) and Figure 7 The EHT TB (trigger-based) PPDU in (f). The EHT PPDU format is similar to the HE PPDU format in that it includes RL-SIG following L-SIG, but it can include U (generic)-SIG, EHT-SIG, EHT-STF and EHT-LTF following RL-SIG.

[0118] Figure 7In (e), the EHT MU PPDU corresponds to a PPDU carrying one or more data (or PSDU) for one or more users. That is, the EHT MU PPDU can be used for both SU and MU transmissions. For example, the EHT MU PPDU can correspond to a PPDU for one or more receiving STAs.

[0119] Compared to EHT MU PPDU, Figure 7 In (f), the EHT-SIG is omitted from the EHT TB PPDU. The STA that receives the trigger for UL MU transmission (e.g., trigger frame or trigger response schedule (TRS)) can perform UL transmission based on the EHT TB PPDU format.

[0120] The L-STF, L-LTF, L-SIG, RL-SIG, U-SIG (general signal), and EHT-SIG fields can be encoded and modulated so that even conventional STAs can attempt demodulation and decoding, and can be mapped based on a determined subcarrier frequency interval (e.g., 312.5 kHz). These can be referred to as pre-EHT modulated fields. Next, the EHT-STF, EHT-LTF, data, and PE fields can be encoded and modulated to be demodulated and decoded by an STA that has successfully decoded a non-conventional SIG (e.g., U-SIG and / or EHT-SIG) and obtained the information contained in that field, and can be mapped based on a determined subcarrier frequency interval (e.g., 78.125 kHz). These can be referred to as EHT modulated fields.

[0121] Similarly, in the HE PPDU format, the L-STF, L-LTF, L-SIG, RL-SIG, HE-SIG-A, and HE-SIG-B fields can be referred to as pre-HE modulation fields, and the HE-STF, HE-LTF, data, and PE fields can be referred to as HE modulation fields. Additionally, in the VHT PPDU format, the L-STF, L-LTF, L-SIG, and VHT-SIG-A fields can be referred to as non-VHT modulation fields, and the VHT STF, VHT-LTF, VHT-SIG-B, and data fields can be referred to as VHT modulation fields.

[0122] Included Figure 7In the EHT PPDU format, U-SIG can be configured based on, for example, two symbols (e.g., two consecutive OFDM symbols). Each symbol used for U-SIG (e.g., an OFDM symbol) can have a duration of 4 μs, and U-SIG can have a total duration of 8 μs. Each symbol of U-SIG can be used to transmit 26 bits of information. For example, each symbol of U-SIG can be transmitted and received based on 52 data tones and 4 pilot tones.

[0123] U-SIGs can be constructed in 20 MHz units. For example, if an 80 MHz PPDU is constructed, U-SIGs can be replicated. That is, the same four U-SIGs can be included in an 80 MHz PPDU. PPDUs with bandwidths exceeding 80 MHz can include different U-SIGs.

[0124] For example, A uncoded bits can be sent via U-SIG. The first symbol of U-SIG (e.g., U-SIG-1 symbol) can send the first X bits of the total A-bit information, and the second symbol of U-SIG (e.g., U-SIG-2 symbol) can send the remaining Y bits of the total A-bit information. The A-bit information (e.g., 52 uncoded bits) may include a CRC field (e.g., a 4-bit field) and a tail field (e.g., a 6-bit field). For example, the tail field can be used to terminate the lattice structure of the convolutional decoder and can be set to 0.

[0125] Bit information sent via U-SIG can be divided into version-independent bits and version-dependent bits. For example, U-SIG can be included in... Figure 7 The new PPDU format (e.g., UHR PPDU format) not shown in the figure, and may be included in the format of the U-SIG field included in the EHT PPDU format and the format of the U-SIG field included in the UHR PPDU format, the version-independent bits may be the same, and some or all of the version-related bits may be different.

[0126] For example, the size of the version-independent bits in U-SIG can be fixed or variable. Version-independent bits can be assigned only to the U-SIG-1 symbol, or to both the U-SIG-1 and U-SIG-2 symbols. Version-independent bits and version-dependent bits can be referred to by various names, such as first control bits and second control bits.

[0127] For example, the version-independent bits of U-SIG may include a 3-bit Physical Layer Version Identifier (PHY Version Identifier), which can indicate the PHY version (e.g., EHT, UHR, etc.) of the transmitted / received PPDU. The version-independent bits of U-SIG may include a 1-bit UL / DL Flag field. The first value of the 1-bit UL / DL Flag field is related to UL communication, and the second value is related to DL communication. The version-independent bits of U-SIG may include information about the length of the Transmission Opportunity (TXOP) and information about the BSS color ID.

[0128] For example, the version-related bits of U-SIG may include information that directly or indirectly indicates the type of PPDU (e.g., SUPPDU, MU PPDU, TB PPDU, etc.).

[0129] Information required for PPDU transmission and reception can be included in the U-SIG. For example, the U-SIG may also include information about bandwidth, information about the MCS technique applied to non-traditional SIGs (e.g., EHT-SIG or UHR-SIG), information indicating whether DCM (dual-carrier modulation) techniques (e.g., techniques used to achieve effects similar to frequency diversity by reusing the same signal on two subcarriers) are applied to non-traditional SIGs, information about the number of symbols used for non-traditional SIGs, and information about whether non-traditional SIGs are generated across the entire frequency band.

[0130] Some of the information required for PPDU transmission and reception may be included in U-SIG and / or non-traditional SIG (e.g., EHT-SIG or UHR-SIG). For example, information about the type of non-traditional LTF / STF (e.g., EHT-LTF / EHT-STF or UHR-LTF / UHR-STF), the length of the non-traditional LTF and the CP (cyclic prefix) length, the GI (guard interval) applicable to the non-traditional LTF, the preamble punching information applicable to the PPDU, and the resource unit (RU) allocation may be included only in U-SIG, only in non-traditional SIG, or may be indicated by a combination of information included in U-SIG and information included in non-traditional SIG.

[0131] Preamble puncturing can represent the transmission of a PPDU where no signal is present in one or more frequency units within the bandwidth of the PPDU. For example, the size of the frequency unit (or the resolution of the preamble puncturing) can be defined as 20 MHz, 40 MHz, etc. For example, preamble puncturing can be applied to PPDU bandwidths of a predetermined size or larger.

[0132] exist Figure 7In the examples, non-traditional SIGs such as HE-SIG-B and EHT-SIG can include control information for receiving STAs. Non-traditional SIGs can be transmitted on at least one symbol, and a symbol can have a length of 4 μs. Information regarding the number of symbols used for EHT-SIGs can be included in previous SIGs (e.g., HE-SIG-A, U-SIG, etc.).

[0133] Non-traditional SIGs such as HE-SIG-B and EHT-SIG can include both public and user-specific fields. These public and user-specific fields can be encoded separately.

[0134] In some cases, the common field can be omitted. For example, in compressed mode using non-OFDMA (Orthogonal Frequency Division Multiple Access), the common field can be omitted, and multiple STAs can receive PPDUs (e.g., the data field of the PPDU) through the same frequency band. In uncompressed mode using OFDMA, multiple users can receive PPDUs (e.g., the data field of the PPDU) through different frequency bands.

[0135] The number of user-specific fields can be determined based on the number of users. A user block field can include up to two user fields. Each user field can be associated with either a MU-MIMO allocation or a non-MU-MIMO allocation.

[0136] The common fields may include CRC bits and tail bits, where the length of the CRC bits can be determined to be 4 bits, and the length of the tail bits can be determined to be 6 bits and set to 000000. The common fields may include RU allocation information. RU allocation information may include bit settings regarding the RUs assigned to multiple users (i.e., multiple receiving STAs).

[0137] An RU can include multiple subcarriers (or tones). RUs can be used when transmitting signals to multiple STAs based on OFDMA technology. Additionally, RUs can be defined even when transmitting signals to a single STA. Resources can be allocated in units of RUs for non-traditional STFs, non-traditional LTFs, and data fields.

[0138] The appropriate RU size can be defined based on the PPDU bandwidth. RUs can be defined the same or different for the applied PPDU format (e.g., HEPPDU, EHT PPDU, UHR PPDU, etc.). For example, in the case of an 80 MHz PPDU, the RU layout for HEPPDU and EHT PPDU can be different. The appropriate RU size, number and location of RUs, DC (direct current) subcarrier locations and numbers, empty subcarrier locations and numbers, guard subcarrier locations and numbers, etc., for each PPDU bandwidth can be referred to as the tone scheme. For example, a tone scheme for high bandwidth can be defined as multiple iterations of a low-bandwidth tone scheme.

[0139] RUs of various sizes can be defined as 26-tone RUs, 52-tone RUs, 106-tone RUs, 242-tone RUs, 484-tone RUs, 996-tone RUs, 2×996-tone RUs, 3×996-tone RUs, etc. MRUs (Multiple RUs) differ from multiple individual RUs and correspond to a group of subcarriers composed of multiple RUs. For example, an MRU can be defined as 52+26 tones, 106+26 tones, 484+242 tones, 996+484 tones, 996+484+242 tones, 2×996+484 tones, 3×996 tones, or 3×996+484 tones. Furthermore, the multiple RUs constituting an MRU can be consecutive or non-consecutive in the frequency domain.

[0140] The specific size of the RU can be reduced or expanded. Therefore, the specific size of each RU in this disclosure (i.e., the number of corresponding tones) is not limiting but illustrative. In addition, in this disclosure, the number of RUs can vary depending on the RU size within a predetermined bandwidth (e.g., 20 MHz, 40 MHz, 80 MHz, 160 MHz, 320 MHz...).

[0141] Figure 7 The names of each field in the PPDU format are exemplary, and the scope of this disclosure is not limited to these names. Furthermore, the examples in this disclosure can be applied to... Figure 7 The PPDU format shown and based on Figure 7 A new PPDU format that excludes some fields and / or adds some fields, based on the PPDU format.

[0142] Multiple Access Point (MAP) Operation

[0143] The following will describe an example of this disclosure for multi-access point (MAP) operation.

[0144] MAP operations can be defined as operations between a primary AP (or sharing AP) and a secondary AP (or shared AP).

[0145] The master AP initiates and controls MAP operations for sending or receiving data among multiple APs. The master AP groups slave APs and manages links with them to share information. The master AP manages information about the BSSs configured for the slave APs and the STAs associated with those BSSs.

[0146] Slave APs can be associated with master APs and share control information, management information, and data traffic. Slave APs perform the basic functions of APs that can establish a BSS in a wireless LAN in the same way.

[0147] In MAP operations, a STA can be associated with a slave AP or a master AP to configure a BSS.

[0148] In a MAP environment, the master AP and slave APs can perform direct transmission or reception with each other. The master AP and STA may not be able to perform direct transmission or reception with each other. A slave AP (e.g., a slave AP associated with a STA) can perform direct transmission or reception with the STA. One of the slave APs can become the master AP.

[0149] MAP operation is a technique in which at least one AP sends and receives information to at least one STA. For example, Coordinated Time Division Multiple Access (C-TDMA) techniques that divide the allocation between APs along the time axis, Coordinated Orthogonal Frequency Division Multiple Access (C-OFDMA) techniques that divide the allocation between APs along the frequency axis, and Coordinated Spatial Reuse (C-SR) techniques that utilize spatial reuse can be applied to MAP operation. Alternatively, Coordinated Beamforming (C-BF) or Joint Beamforming techniques that cooperate to perform simultaneous transmission or reception can also be applied to MAP operation.

[0150] Figure 8 This is a diagram illustrating various transmitting or receiving technologies that can be applied in a MAP environment according to this disclosure.

[0151] When a BSS AP performs a transmission to a BSS STA using existing methods, it can be referred to as Single Transmission (STX). In STX, there is a problem of degraded transmission or reception performance for users / STAs located at the cell edge due to interference with neighboring APs. For example, as... Figure 8 In (a), when AP1 and AP2 transmit to STA 1 and STA 2 simultaneously in the same frequency bandwidth, a collision may occur on the wireless medium.

[0152] In MAP technology, performance can be improved by reducing inter-symbol interference (ISI) through cooperation or joint transmission between neighboring APs. For example, in Figure 8 In the C-OFDMA method of (b), AP1 can perform the transmission to STA 1 in the first bandwidth, and at the same time, AP2 can perform the transmission to STA 2 in the second bandwidth, thereby avoiding interference. Figure 8 The example in (c) illustrates a cooperative beamforming or nulling technique, wherein AP1 nulls the interference to AP2 and / or STA2 when performing a transmission to STA1, and AP2 nulls the interference to AP1 and / or STA1 when performing a transmission to STA2. Figure 8 (d) illustrates the AP selection method, where the AP with good channel conditions among neighboring APs performs the transmission. (As shown in...) Figure 8 In example (e), multiple APs can be applied to cooperate to perform joint transmission (JTX) or joint reception (JRX) simultaneously, and further, joint MU-MIMO can be supported.

[0153] RSN Operations

[0154] For reference Figure 3 The described process allows for the execution of an authentication process following the discovery process between the STA and AP in an open system manner, and also allows for the execution of an association process. This process can be referred to as step 0, which searches for support for a robust secure network (RSN) and establishes authentication and association.

[0155] Upon successful completion of step 0, step 1 can be performed to ensure the pairwise master key (PMK) and user authentication via IEEE 802.1X / EAP (Extensible Authentication Protocol) or a pre-shared key (PSK). The mutual authentication methods applied here can include 802.1X / EAP, PSK, or SAE (simultaneous authentication of equals). For example, for the 802.1X / EAP authentication method, the PMK can be generated from the master session key (MSK) after authentication between the STA and the Remote Authentication Dial-In User Service (RADIUS). For user authentication via PSK, the AP and STA can directly set the PMK in the same manner as with PSK. For user authentication via SAE, the AP and STA can directly set the PMK using the operation values ​​of mutual authentication and the authentication process through the SAE authentication procedure.

[0156] Following step 1, step 2 can be performed to verify whether the other party has the same PMK using an EAPoL-Key frame and to generate and share an encryption key. Step 2 may include a process of mutually confirming PMK generation via a four-way handshake and generating and delivering a group key (e.g., a group temporary key (GTK)). A pairwise transient key (PTK), a key confirmation key (KCK), a key encryption key (KEK), and a temporary key (TK) can be generated via the four-way handshake.

[0157] Specifically, PMK can be generated from MSK in step 1, and PTK can be generated from PMK in step 2. Here, PTK is set to KCK, KEK, and TK respectively. GTK can be generated from AP and delivered to STA. When AP wants to generate a new GTK, it can perform a handshake with STA and deliver the new GTK to STA.

[0158] To verify that the STA and AP have the same PMK, for 802.1X / EAP, the same MSK is set between the STA and AS based on the user authentication result between the STA and the Authentication Server (AS), and the AS delivers the corresponding MSK to the AP. The STA and AP can mutually confirm whether they have the PMK, i.e., the symmetric key generated from the MSK, through a four-way handshake. For PSK, the authentication process can be replaced by mutually verifying whether the PMK generated from the pre-set PSK between the AP and STA is ensured via a four-way handshake. For SAE, the pre-set PMK between the AP and STA can be mutually verified via a four-way handshake.

[0159] The STA and AP can also verify that they have the same PMK by mutually verifying that they have generated the same PTK. For example, the PMK can be confirmed through messages 2 and 3 of the four-way handshake. Specifically, in message 2, the STA can send the KCK of its generated PTK to the AP by including the KCK in the key MIC field. In message 3, the AP can send the KCK of its generated PTK to the STA by including the KCK in the key MIC field. In this way, the STA (AP) can verify that the AP (STA) has generated the same PTK as its PTK and confirm that the AP (STA) has the same PMK as its PMK. Furthermore, in message 1, the value of the key MIC field can be set to 0, and in message 4, the KCK value can be included in the key MIC field.

[0160] In this way, a security key for encrypting data to be sent and received between the STA and the AP can be generated in step 2. In the RSN, a different security key is generated for each STA associated with the AP, and another security key is generated when the STA is reassociated with another AP.

[0161] Based on the TK generated by the 4-way handshake in step 2, data encryption can be performed using Temporary Key Integrity Protocol (TKIP), Cipher Block Linked Message Authentication Code Protocol (CCMP), Galois / Counter Mode Protocol (GCMP), etc., which can be referred to as step 3.

[0162] The MSK, PSK, PMK, PTK, KCK, KEK, and TK mentioned above correspond to pair keys, i.e., paired keys between the AP and STA. Unlike pair keys, a group key can be generated based on the group master key (GMK) to allow the AP to generate secure keys for group-addressed frames (such as beacon frames). The GMK is randomly set by the AP. The group temporary key (GTK) is generated from the GMK using a pseudo-random function (PRF) and corresponds to a one-way group key from the AP to the STA.

[0163] Figure 9 This is a diagram illustrating the four-way handshake process to which this disclosure can be applied.

[0164] The STA corresponds to the requester, and the AP corresponds to the authenticator. When the STA has or knows the PMK and the AP has or knows both the PMK and GMK, a four-way handshake can be performed to generate and confirm the PTK and GTK between the AP and the STA.

[0165] ANonce and SNonce correspond to the factors used in the PRF function used to generate the PTK. ANonce can correspond to a random number generated by the access point (i.e., the authenticator). SNonce can correspond to a random number generated by the STA (i.e., the requester). The PRF function can correspond to a function that generates the PTK based on, for example, PMK, ANonce, SNonce, the requester's MAC address, and the authenticator's MAC address.

[0166] In S810, message 1 is sent from the AP to the STA via unicast, and the EAPOL-key frame may include ANOnce information. When the AP generates the PMK, the PMKID can be included in the key data field of the EAPOL-key frame. The STA can generate the PTK based on the information received from the AP, and can generate KCK, KEK, and TK based on the PKT.

[0167] In S820, message 2 is sent from STA to AP via unicast, and the EAPOL-key frame may include SNonce information and Key Message Integrity Code (MIC). For example, the key MIC of message 2 may have a value based on KCK generated by the STA. The AP may generate PTK based on information received from the STA, and may generate KCK, KEK, and TK based on the PTK. The AP may verify whether the AP and STA have generated the same PTK by comparing the KCK value of the PTK generated according to the value included in message 2 with the KCK value associated with the key MIC value included in message 2. Furthermore, if needed, the AP may generate GTK. GTK may be generated by the AP from GMK without the participation of the STA.

[0168] In S830, message 3 is sent from the AP to the STA via unicast, and the EAPOL-key frame may include the MIC (i.e., the KCK value corresponding to the PTK generated by the AP) and encrypted GTK information. The encrypted GTK in message 3 can be encrypted based on the KEK generated by the AP and can be included in the key data field. The STA can store the PTK in the PKT-SA (PKT-Security Association) and the GTK in the GTK-SA.

[0169] In S840, message 4 is sent from STA to AP via unicast, and the EAPOL-key frame may include MIC information. When authentication is completed via MIC, AP can store PTK in PTK-SA and GTK in GTK-SA.

[0170] When the four-way handshake is successfully completed in this manner, the virtual control port that was blocking all traffic can be unblocked, and encrypted traffic can be sent and received. Afterward, all unicast traffic can be encrypted using PTK, and all multicast / broadcast traffic can be encrypted using GTK.

[0171] RSNA Confidentiality and Integrity Protocol

[0172] For RSNA, authentication mechanisms, key management algorithms, cryptographic key establishment, cryptographic mechanisms, fast BSS transformation (FT), and cryptographic encapsulation for robust management frames can be defined for STA. For example, cryptographic mechanisms may include Counter Mode (CTR) protocol with Cipher Block Chaining Message Authentication Code (CBC-MAC) and Galois / Counter Mode (GCMP) protocol.

[0173] RSNA security can include algorithms and procedures such as Temporary Key Integrity Protocol (TKIP), CCMP, GCMP, Broadcast / Multicast Integrity Protocol (BIP), RSNA establishment and termination procedures, key management procedures (e.g., key distribution), etc. For example, RSNA establishment and termination procedures can include IEEE 802.1X authentication, peer simultaneous authentication (SAE) authentication, opportunistic wireless encryption (OWE) as defined in Internet Engineering Task Force Mandatory (IETF) Request for Request Note (RFC) 8110, etc.

[0174] The Counter Mode (CTR) protocol (CCMP) with Cryptographic Block Chain Message Authentication Code (CBC-MAC) is described below.

[0175] CCMP is a protocol that provides data confidentiality, authentication, integrity, and reproducibility protection. CCMP is based on the CCM (Content Management Module) of the Advanced Encryption Standard (AES) encryption algorithm. CCM combines CTR (Content Transaction Transmission) for data confidentiality and CBR-MAC (Content Transaction Transmission MAC) for authentication and integrity. CCM can protect the integrity of selected portions of the MPDU data fields and both the MPDU header (MAC header).

[0176] Figure 9 This is a diagram illustrating an example of an extended CCMP MPDU that can be applied to this disclosure.

[0177] For Security Protocol Version 0 (PV0) MPDUs, CCMP-128 processing expands the original MPDU size by 16 octets (i.e., 8 octets for the CCMP header field and 8 octets for the MIC field). CCMP-256 processing expands the original MPDU size by 24 octets (i.e., 8 octets for the CCMP header field and 16 octets for the MIC field). The CCMP header field consists of the Block Number (PN), the Extended Initialization Vector (ExtIV), and the Key ID subfield. PN is a 48-bit PN represented as a 6-octet array. PN5 is the most significant octet of PN, and PN0 is the least significant octet. The third octet of the CCMP header is reserved. The ExtIV subfield (bit 5 (B5) of the Key ID octet) is always set to 1 for CCMP, bits 6 (B6) and 7 (B7) are the Key ID subfield, and the remaining bits of the Key ID octet are reserved.

[0178] Figure 10 This indicates that the CCMP encapsulation block diagram disclosed herein can be applied.

[0179] Additional Authentication Data (AAD) can be constructed from the MAC header of the plaintext MPDU. A Nonce can be constructed based on A2 (address 2), the priority of the plaintext MPDU, and an increased PN. AAD and Nonce can be used with data and TK for CCM encryption. A CCMP header can be constructed based on an increased PN and key ID. The data and MIC, as the result of CCM encryption, can be used with the MAC header and CCMP header to construct an encrypted MPDU, such as... Figure 9 As shown in the example.

[0180] Figure 11 An example of a regular AAD format.

[0181] Figure 11 The example in (a) can correspond to an example of a regular AAD construction for a PV0 MPDU. The Frame Control (FC), A1 (address 1), A2 (address 2), A3 (address 3), and Sequence Control (SC) fields can always be included in the regular AAD when they are included in the MAC header. The length of the AAD can vary depending on the presence or absence of the QoS Control (QC) field and the Address 4 (A4) field. For a regular AAD, for example, the AAD length can be 22 octets when neither QC nor A4 is present, 24 octets when QC is present and A4 is absent, 28 octets when QC is absent and A4 is present, and 30 octets when both QC and A4 are present.

[0182] AAD is constructed from the MPDU header. (See reference...) Figure 11 (b) The standard AAD does not include the duration / ID field of the MAC header, nor does it include the HT control field of the MAC header. This is to ensure that fields whose contents may be changed or inserted / deleted during operations such as retransmission are not included in the standard AAD.

[0183] Additionally, some subfields of the Frame Control (FC) field in the MAC header can be masked. Masking means that the corresponding subfield / field in the MAC header is included in the AAD by changing its value to 0.

[0184] For example, the subfields masked in the FC field of a regular AAD are as follows: The three LSBs (i.e., bits 4, 5, and 6) of the subtype subfield of the data frame are masked, and bit 7 is not modified. The retry subfield is masked; The power management subfield (i.e., bit 12) is masked; More data subfields (i.e., bit 13) are masked; The protected frame subfield (i.e., bit 14) is not modified (i.e., it is left as 1). The +HTC subfield (i.e., bit 15) is masked in all data frames that include QoS control fields, or is otherwise left unmodified. Other subfields of the FC field are not modified.

[0185] For example, the sequence number subfield in the sequence control (SC) field of a regular AAD can be masked.

[0186] Despite Figure 11 The example is not shown, but when the QoS Control (QC) field is included in a regular AAD, the QC field can be included in the regular AAD if at least one of the MSDU Priority subfield, QC Traffic Identifier (TID) subfield, A-MSDU Support subfield, A-MSDU Presence subfield, and A-MSDU Type subfield is present in the MAC header. Other subfields can be masked in the QC field of a regular AAD. In other words, the End of Service Period (EOSP) subfield, ACK Policy Indicator subfield, TXOP Limit subfield, Queue Size subfield, TXOP Duration Request subfield, and AP Power Saving (PS) Buffer Status subfield can be masked and may not be used to construct a regular AAD.

[0187] Figure 12 This indicates that the CCMP decapsulation block diagram disclosed herein can be applied.

[0188] An AAD can be constructed from the MAC header of an encrypted MPDU. A random number can be constructed based on the A2 and priority of the encrypted MPDU, as well as the PN. The AAD and random number can be used together with the MIC, data, and key for CCM decryption. The result of CCM decryption can be re-verified along with the MAC header to obtain the plaintext MPDU. Re-verification can be based on the PN and a re-verification counter.

[0189] The Broadcast / Multicast Integrity Protocol (BIP) is described below.

[0190] BIP provides data integrity and reproducibility protection for group-addressed robust management frames after establishing an Integrity Group Temporary Key Security Association (IGTKSA). For example, BIP provides data integrity and reproducibility protection for beacon frames after establishing a beacon (BIGTKSA). BIP can use IGTK or BIGTK to compute the MAC Management PDU (MMPDU) MIC. The Management MIC element (MME) can be located after all other elements in the management frame body and before the FCS. In other words, the MME can be included as the last element of the management frame body. The MME may include an element ID field, a length field, a key ID field, an IGTK block number (IPN) / BIGTK block number (BIPN) field, and a MIC field.

[0191] The standard AAD used for BIP can be constructed based on FC, A1, A2 and A3, and the retry subfield (bit 11), power management subfield (bit 12) and more data subfield (bit 13) in FC can be masked, while other subfields can remain unmodified.

[0192] The Galois / Counter Mode Protocol (GCMP) is described below.

[0193] GCMP is a protocol that provides data confidentiality, authentication, integrity, and reproducibility protection. EHT RSNA STA supports GCMP-256. GCMP is based on GCM, which uses the Advanced Encryption Standard (AES) encryption algorithm. GCM can protect the integrity of selected portions of the MPDU data fields and both the MPDU header (MAC header).

[0194] Figure 13 This is a diagram illustrating an example of an extended GCMP MPDU that can be applied to this disclosure.

[0195] GCMP processing expands the original MPDU size by 24 octets (i.e., 8 octets for the GCMP header fields and 16 octets for the MIC field). The GCMP header fields are constructed from the block number (PN) and key ID subfield. PN is a 48-bit PN represented as a 6-octet array. PN5 is the most significant octet of PN, and PN0 is the least significant octet. The third octet of the GCMP header is reserved. The ExtIV subfield of the key ID octet (bit 5 (B5)) is always set to 1 for GCMP, bits 6 (B6) and 7 (B7) are the key ID subfields, and the remaining bits of the key ID octet are reserved.

[0196] Figure 14 This indicates that the GCMP encapsulation block diagram disclosed herein can be applied.

[0197] Additional Authentication Data (AAD) can be constructed from the MAC header of a plaintext MPDU. A random number can be constructed based on address 2 (A2) of the plaintext MPDU and an enlarged PN. AAD and Nonce can be used together with data and TK for GCM encryption. A GCMP header can be constructed based on an enlarged PN and a key ID. Data resulting from CCM encryption can be used together with the MAC and CCMP headers to construct an encrypted MPDU, such as... Figure 13 As shown in the example.

[0198] Due to the construction and reference of conventional AADs applied to GCMP Figure 11 The descriptions are identical, therefore overlapping descriptions have been omitted.

[0199] Figure 15 This indicates that the GCMP decapsulation block diagram disclosed herein can be applied.

[0200] The AAD can be constructed from the MAC header of an encrypted MPDU. A random number can be constructed based on the encrypted MPDU and the A2 of the PN. The AAD and the random number can be used together with the data and key for GCM decryption. The data resulting from GCM decryption can be reproduced and verified along with the MAC header to obtain the plaintext MPDU. Reproducibility verification can be based on the PN and a reproducibility counter.

[0201] Block ACK Request (BAR) Frame

[0202] Figure 16 This is a diagram illustrating an exemplary format of a block ACK request frame to which the present disclosure may be applied.

[0203] A block ACK request frame can be used to request the transmission of a block ACK frame that includes multiple acknowledgment responses in a single frame, thereby improving channel efficiency. For example, a first STA (e.g., an AP) can request the reception results for multiple MPDUs via a block ACK request frame, and a second STA that receives the block ACK request frame can send a block ACK frame that includes acknowledgment responses for the multiple MPDUs based on the corresponding request.

[0204] like Figure 16 As shown, a Block ACK Request (BAR) frame can include a BAR control field and a BAR information field in the frame body.

[0205] The BAR control field may include the BAR type indicating the type of the block ACK request frame (e.g., compressed, multiple TID, multicast with retries (GCR), etc.), TID information (TID_INFO), etc.

[0206] The BAR information field can be based on the type of the block ACK request frame (e.g., block ACK request frame variant type) indicated by the BAR type field / subfield within the BAR control information.

[0207] For example, when indicating the compressed block ACK request frame type (e.g., compressed block ACK frame type or extended compressed block ACK frame type), the BAR information field format corresponding to the compressed block ACK request may include the block ACK start sequence control subfield.

[0208] For example, the Block ACK Start Sequence Control subfield may include a Fragment Number subfield and a Start Sequence Number subfield. Here, the Fragment Number subfield is set to 0, and the Start Sequence Number subfield may include the sequence number of the first MSDU or A-MSDU to which the corresponding Block ACK Request Frame was sent.

[0209] As another example, when indicating the type of multi-TID (multi-STA) block ACK request frame, the format of the BAR information field corresponding to the multi-TID block ACK request may include a per-TID information subfield and a block ACK start sequence control subfield for each TID.

[0210] For example, each TID information subfield may include a 4-bit TID value subfield. Furthermore, the block ACK start sequence control subfield may include a fragment number subfield and a start sequence number subfield. Here, the fragment number subfield is set to 0, and the start sequence number subfield may include the sequence number of the first MSDU or A-MSDU to which the corresponding block ACK request frame was sent.

[0211] In this respect, the TID_INFO subfield of the BAR control field of the multi-TID block ACK request frame can determine the number of TIDs present in the multi-TID block ACK request frame, which is given as TID_INFO + 1. For example, when the TID_INFO subfield is set to 2, this may mean that there are three TID values ​​in the BAR information field of the multi-TID block ACK request frame.

[0212] As another example, when indicating the GCR block ACK request frame type, the BAR information field format corresponding to the GCR block ACK request may include a GCR group address subfield and a block ACK start sequence control subfield. Here, the GCR group address subfield may include the MAC address of the group requesting the receive status. Furthermore, the block ACK start sequence control subfield may include a fragment number subfield and a start sequence number subfield. Here, the fragment number subfield is set to 0, and the start sequence number subfield may include the sequence number of the first MSDU or A-MSDU that sent the corresponding block ACK request frame.

[0213] As another example, when indicating the GLK-GCR block ACK request frame type, the BAR information field format corresponding to the GCR-GCR block ACK request may include a block ACK start sequence control subfield. Here, the block ACK start sequence control subfield may include a fragment number subfield and a start sequence number subfield. Here, the fragment number subfield is set to 0, and the start sequence number subfield may include the sequence number of the first MSDU or A-MSDU that sent the corresponding block ACK request frame.

[0214] Methods for supporting encryption / decryption of Block Acknowledgment Request (BAR) frames

[0215] In traditional wireless LAN systems, for individually addressed data frames (e.g., unicast-based data frames) and management frames, encryption / decryption based on the Temporary Key Integrity Protocol (TKIP), the CTR Protocol with CBC-MAC (CCMP), or the GCM Protocol (GCMP) can be performed / applied using pairwise transient keys (PTKs). Furthermore, for group-addressed frames (e.g., broadcast-based data frames), encryption / decryption based on TKIP / CCMP / GCMP can be performed / applied using a group temporary key (GTK). That is, CCMP / GCMP are secure protocols for performing encryption / decryption, where PTK-based TKs can be used in single-user (SU) scenarios, and GTK-based TKs can be used in multi-user (MU) scenarios. CCMP / GCMP ensures the confidentiality and integrity of data frames and management frames.

[0216] Furthermore, for group-addressed management frames, integrity checks based on BIP can be performed using the Integrity Group Temporary Key (IGTK). Specifically, in the case of beacon frames, integrity checks based on BIP can be performed using the Beacon Integrity Group Temporary Key (BIGTK). In the case of BIP, the IGTK / BIGTK-based TK is used to generate a Message Integrity Code (MIC) for the frame body of the corresponding data frame, and integrity checks can be performed based on this. That is, unlike CCMP / GCMP, BIP can ensure the integrity of only data frames and management frames.

[0217] The methods for building MPDUs based on CCMP and GCMP and the methods for building management MPDUs (MMPDUs) based on BIP have the following differences.

[0218] First, in the case of CCMP / GCMP, the sending STA encrypts the data portion using CCM / GCM, sends the encrypted data, and the receiving STA can decrypt the received encrypted data. In contrast, in the case of BIP, the sending STA does not encrypt the data portion and can execute the corresponding protocol to generate a MIC for integrity verification of the data in the frame body.

[0219] Next, in the case of CCMP / GCMP, the MPDU can be constructed and sent / received in the following order: MAC header, CCMP / GCMP header, encrypted data, MIC (or encrypted MIC in the case of CCMP), and FCS. In contrast, in the case of BIP, the MPDU can be constructed and sent / received in the following order: MAC header, management frame body including MME (management MIC element), and FCS. In this paper, since the MME replaces the role of the CCMP / GCMP header, the MME can include a key ID field, IPN / BIPN, and MIC information.

[0220] As described above, protection is supported for data frames and management frames, including beacon frames, within group-addressed frames. However, protection is not supported for control frames; therefore, control frames are sent and received without the application of protocols for encryption / decryption and / or integrity verification.

[0221] For example, ACK frames, block ACK (BlockAck, Block Ack, BA) frames, and block ACK request frames correspond to the types of control frames. When a sending STA transmits data, a receiving STA can send an ACK for the corresponding data to the sending STA. In this case, a STA supporting A (aggregated)-MPDU can configure an ACK corresponding to the A-MPDU and send it as a block ACK.

[0222] A block ACK request frame can be sent by the transmitting STA to receive a block ACK from the receiving STA. In other words, when the transmitting STA sends a block ACK request frame to the receiving STA, the receiving STA can send a block ACK frame to the corresponding transmitting STA. Based on this, the block ACK request frame can be used to obtain ACK information for previous frames sent from the TXOP, or to initialize (e.g., clear) the receive reordering buffer of the receiving STA.

[0223] In this respect, when the information of the block ACK request frame is exposed to a third STA (e.g., an attacking STA), ACK information confirming whether data is being sent and received between the transmitting and receiving STAs can be obtained, thus interfering with whether transmission and reception are being performed between the transmitting and receiving STAs. As a result, attacks on block ACK request frames may lead to degradation of data transmission and reception capabilities and waste of power / medium.

[0224] With this in mind, this disclosure proposes a security technique for ensuring the confidentiality and integrity of block ACK request frames transmitted and received between the sending STA and the receiving STA.

[0225] Furthermore, in the description of this disclosure, it is assumed that the STAs that send and receive block ACK request frames according to this disclosure are UHR STAs (and / or STAs after UHR). As an example, when utilizing a block ACK request frame according to this disclosure, it can be assumed that all receiving STAs receiving a block ACK request frame sent by an AP that is a sending STA are UHR STAs. In other words, if a block ACK request frame configured according to the proposed method of this disclosure is received by an STA before UHR (e.g., an EHT / HE STA, etc.), an error may occur during the decoding of the corresponding block ACK request frame.

[0226] Furthermore, although this disclosure is described using security techniques for block ACK request frames in control frames as a representative example, the methods proposed in this disclosure can be extended and applied to other types of control frames besides block ACK request frames.

[0227] In this disclosure, performing confidentiality and integrity checks on block ACK request frames can be interpreted as extending and applying CCMP / GCMP to block ACK request frames. In this respect, matters specific to control frames can be defined separately for the existing definition of CCMP / GCMP, or a new CCMP / GCMP-based separate protocol can be defined for confidentiality and integrity checks of control frames.

[0228] In the following, specific examples of the application of encryption / decryption in this disclosure are described as methods for supporting / performing protection (e.g., confidentiality and integrity verification) against block ACK request frames.

[0229] The names and values ​​of fields, subfields, elements, parameters, keys, etc., presented in this disclosure are exemplary and are not limited to these names and values. Furthermore, unless otherwise specified, an STA can be an AP STA or a non-AP STA.

[0230] Figure 17 This is a diagram used to describe the operation of the first STA according to this disclosure.

[0231] In step S1710, the first STA can generate a block ACK request frame based on the encryption protocol.

[0232] In this respect, the corresponding block ACK request frame may include encrypted information based on an encryption protocol. Here, the encrypted information may be based on the block ACK request control field and the block ACK request information field within the frame body of the block ACK request frame. In other words, the encrypted information in this disclosure may be based on some fields within the frame body of the block ACK request frame.

[0233] According to this disclosure, encryption of a block ACK request frame can be performed based on key information associated with the protection of the corresponding block ACK request frame. As an example, for a individually addressed block ACK request frame, the key information may correspond to an existing PTK applied to an existing data frame, or to a new PTK (i.e., a PTK distinct from the existing PTK) used for the block ACK request frame. Alternatively, for a group-addressed block ACK request frame, the key information may correspond to an existing GTK / IGTK / BIGTK applied to an existing broadcast, or to a new GTK (i.e., a GTK distinct from the existing GTK / IGTK / BIGTK) used for the block ACK request frame.

[0234] According to this disclosure, a block ACK request frame may include MIC information calculated based on key information related to the protection of the corresponding block ACK request frame. When the corresponding encryption protocol is CCMP, encryption may also be applied to the MIC information. When the corresponding encryption protocol is GCMP, encryption may not be applied to the MIC information. Additionally, CCMP-128 or CCMP-256 may be used as cipher suites against CCMP. GCMP-128 or GCMP-256 may be used as cipher suites against GCMP.

[0235] According to this disclosure, when the corresponding encryption protocol is CCMP and the encrypted information is based on the block ACK request control field, the corresponding encrypted information may include multiple non-contiguous encrypted fields. For example, a CCMP MPDU for a block ACK request frame includes an encrypted block ACK request control field (i.e., a first encrypted text) and an encrypted MIC field (i.e., a second encrypted text), and an unencrypted block ACK request information field may be located between the encrypted block ACK request control field and the encrypted MIC field.

[0236] According to this disclosure, when the corresponding encryption protocol is CCMP and the encrypted information is based on the block ACK request information field, the encrypted information may include multiple consecutive encrypted fields. For example, a CCMP MPDU for a block ACK request frame includes an encrypted block ACK request information field and an encrypted MIC field (i.e., a single encrypted text), and an unencrypted block ACK request control field may precede the encrypted block ACK request information field.

[0237] According to this disclosure, when the corresponding encryption protocol is GCMP and the encrypted information is based on either the Block ACK Request Control field or the Block ACK Request Information field, the encrypted information may include a single encrypted field. For example, a GCMP MPDU for a Block ACK Request frame may include an encrypted Block ACK Request Control field (i.e., a single encrypted text), an unencrypted Block ACK Request Information field, and an unencrypted MIC field. Alternatively, a GCMP MPDU for a Block ACK Request frame may include an unencrypted Block ACK Request Control field, an encrypted Block ACK Request Information field (i.e., a single encrypted text), and an unencrypted MIC field.

[0238] According to this disclosure, the encryption protocol header (e.g., a CCMP header or a GCMP header) included in the block ACK request frame may include a field for the key ID and a field for the block number. Furthermore, the encryption protocol header may include information indicating whether protection is supported for the block ACK request frame and / or the MPDU format according to the corresponding encryption protocol (e.g., information indicating what type of MPDU format was constructed).

[0239] When an encryption protocol is applied to a block ACK request frame, the protected frame subfield included in the frame control field of the block ACK request frame can be set to a predefined specific value.

[0240] In step S1720, the first STA can send a block ACK request frame to the second STA.

[0241] At this point, prior to step S1710, between the first STA and the second STA, information indicating whether protection for block ACK request frames is supported can be exchanged via management frames (e.g., beacon frames, probe request / response frames, (re)association request / response frames, etc.). And / or, prior to step S1710, between the first STA and the second STA, information indicating the MPDU format according to the encryption protocol (i.e., information indicating what form of MPDU format was used in the construction) can be exchanged.

[0242] Alternatively or concurrently, the block ACK request frame may include information relating to a block ACK request for data to be received by the second STA. In this case, the key information relating to the protection of the block ACK request frame may be distinguished from the key information used for the protection of the aforementioned data.

[0243] exist Figure 17 The methods described in the examples can be derived from... Figure 1 The first device 100 in the process is used to perform this action. For example, Figure 1One or more processors 102 of the first device 100 may be configured to generate block ACK request frames based on a cryptographic protocol and send the block ACK request frames to a second STA via one or more transceivers. Furthermore, one or more memories 104 of the first device 100 may store data for execution by one or more processors 102. Figure 17 The instructions for the methods described in the examples or the examples described below.

[0244] Figure 18 This is a diagram used to describe the operation of the second STA according to this disclosure.

[0245] In step S1810, the second STA can receive a block ACK request frame based on the encryption protocol from the first STA.

[0246] Because the format and detailed structure of the encryption protocol for the block ACK request frame are different from those of the block ACK request frame. Figure 17 Since the descriptions are the same as those in the previous text, overlapping descriptions will be omitted.

[0247] In step S1820, the second STA can perform decryption and integrity verification on the block ACK request frame.

[0248] For example, the second STA can perform decryption according to the encryption protocol applied to the received block ACK request frame, calculate the MIC value based on the block ACK request control field and / or block ACK request information field in the block ACK request frame, and perform integrity verification by comparing it with the value included in the MIC field of the received block ACK request frame.

[0249] Figure 18 The method described in the example can be derived from Figure 1 The second device 200 in the process is used to perform this. For example, Figure 1 One or more processors 202 of the second device 200 can be configured to receive block ACK request frames based on an encryption protocol from the first STA via one or more transceivers, and perform decryption and integrity verification on the block ACK request frames. Furthermore, one or more memories 204 of the second device 200 can store data for execution by one or more processors 202. Figure 18 The instructions for the methods described in the examples or the examples described below.

[0250] Figure 17 and Figure 18 Examples may correspond to some of the various examples in this disclosure. In the following, examples including... will be described in more detail. Figure 17 and Figure 18 Examples of various examples disclosed herein.

[0251] Implementation Method 1

[0252] This implementation relates to the format of the protected block ACK request frame.

[0253] The lengths of the key ID, IPN / BIPN, and MIC in the MIC field of the CCMP / GCMP header, which is the result of CCMP / GCMP application, are not limited to the previously defined values. For example, in the case of the key ID field, a key ID indicating GTK can have a length of 2 bits, while a key ID indicating IGTK or BIGTK can have a length of 2 octets. Similarly, in the case of the MIC field, the MIC field can have a length of 8 octets, 16 octets, 64 octets, etc. Furthermore, the MIC length can be changed by applying the MIC value to a separate function.

[0254] A block ACK request frame for application protection according to this disclosure can be constructed based on at least one of the formats described below.

[0255] Implementation Method 1-1

[0256] To support protection for block ACK request frames, a format can be constructed that applies CCMP to the BAR control field and BAR information field included in the block ACK request frame.

[0257] The corresponding format can be used to perform encryption / decryption of the BAR control field and BAR information field (i.e., one or more BAR information fields) within a block ACK request frame.

[0258] Specifically, the sending STA can perform CCMP encryption on the BAR control field and BAR information field using a key negotiated / shared with the receiving STA. In the corresponding encryption process, an AAD can be constructed using the frame control field, duration field, RA field, and / or TA field, which are the preceding portions of the BAR control field in the MPDU format.

[0259] In the case of CCMP, the MIC value calculated based on the BAR control field and the BAR information field is constructed into ciphertext form together with the BAR control field and the BAR information field.

[0260] Figure 19 This represents an example of the MPDU format of the cryptographic protocol for block ACK request frames according to this disclosure.

[0261] Reference Figure 19The CCMP MPDU format can be constructed in the following order: Frame Control Field, Duration Field, RA Field, A Field, CCMP Header Field, Ciphertext, and FCS. The corresponding structure is an example, and the scope of this disclosure is not limited thereto.

[0262] In this respect, CCMP header fields may include information related to block numbers (PNs) (e.g., PN0, PN1, PN2, PN3, PN4, PN5, etc.) and / or information related to key IDs.

[0263] As described above, when applying CCMP, the MIC value can be calculated based on the BAR control field and the BAR information field. The calculated MIC value can then be encrypted along with the BAR control field and the BAR information field, and included in the CCMP MPDU in ciphertext form. In other words, CCMP-based encryption can be applied to the entire frame body (i.e., the BAR control field and the BAR information field) and the MIC information of the block ACK request frame before encryption.

[0264] Implementation Methods 1-2

[0265] To support protection for block ACK request frames, a format can be constructed that applies GCMP to the BAR control field and BAR information field included in the block ACK request frame.

[0266] The corresponding format can be used to perform encryption / decryption on the BAR control field and BAR information field (i.e., one or more BAR information fields) within the block ACK request frame.

[0267] Specifically, the sending STA can perform GCMP encryption on the BAR control field and BAR information field using a key negotiated / shared with the receiving STA. In the corresponding encryption process, an AAD can be constructed using the frame control field, duration field, RA field, and / or TA field, which are the preceding portions of the BAR control field in the MPDU format.

[0268] In the case of GCMP, unlike the case of CCMP described above (e.g., implementation 1-1), the MIC value calculated based on the BAR control field and the BAR information field is not encrypted.

[0269] Figure 20 This represents another example of the MPDU format of the cryptographic protocol used for block ACK request frames according to this disclosure.

[0270] Reference Figure 20The GCMP MPDU format can be constructed in the following order: Frame Control Field, Duration Field, RA Field, TA Field, GCMP Header Field, Ciphertext, MIC Field, and FCS. The corresponding structure is an example, and the scope of this disclosure is not limited thereto.

[0271] In this respect, GCMP header fields may include information related to the block number (PN) (e.g., PN0, PN1, PN2, PN3, PN4, PN5, etc.) and / or information related to the key ID.

[0272] As mentioned above, when applying GCMP, the MIC value can be calculated based on the BAR control field and BAR information field without applying encryption to the MIC value. The BAR control field and BAR information field can be encrypted and included in the corresponding GCMP MPDU format as ciphertext. In other words, apart from the MIC information, GCMP-based encryption can be applied to the entire frame body of the block ACK request frame before encryption (i.e., the BAR control field and BAR information field).

[0273] Implementation methods 1-3

[0274] To support protection for block ACK request frames, a format can be constructed that applies CCMP to the BAR control field included in the block ACK request frame.

[0275] The corresponding format can be used to encrypt / decrypt the BAR control field within a block ACK request frame.

[0276] Specifically, the sending STA can perform CCMP encryption on the BAR control field using a key negotiated / shared with the receiving STA. In the corresponding encryption process, an AAD can be constructed using the frame control field, duration field, RA field, and / or TA field, which are the preceding portions of the BAR control field in the MPDU format.

[0277] In the case of CCMP, the MIC value calculated based on the BAR control field is constructed into ciphertext form together with the BAR control field.

[0278] Figure 21 This represents another example of the MPDU format of the encryption protocol for block ACK request frames according to this disclosure.

[0279] Reference Figure 21The CCMP MPDU format can be constructed in the following order: Frame Control Field, Duration Field, RA Field, TA Field, CCMP Header Field, First Ciphertext, BAR Message Field, Second Ciphertext, and FCS. For example, the First Ciphertext can correspond to the encrypted BAR Control Field, and the Second Ciphertext can correspond to the encrypted MIC Field. The BAR Message Field can correspond to unencrypted plaintext. This structure is an example, and the scope of this disclosure is not limited thereto.

[0280] In this respect, CCMP header fields may include information related to block numbers (PNs) (e.g., PN0, PN1, PN2, PN3, PN4, PN5, etc.) and / or information related to key IDs.

[0281] As described above, when applying CCMP, the MIC value can be calculated based on the BAR control field. The calculated MIC value can then be encrypted along with the BAR control field and included in the CCMP MPDU in ciphertext form. In other words, CCMP-based encryption can be applied to some fields of the frame body of the preceding block ACK request frame (i.e., the BAR control field and the BAR information field), and can also be applied to the MIC information.

[0282] Implementation methods 1-4

[0283] To support protection for block ACK request frames, a format can be constructed that applies GCMP to the BAR control field included in the block ACK request frame.

[0284] The corresponding format can be used to encrypt / decrypt the BAR control field within a block ACK request frame.

[0285] Specifically, the sending STA can perform GCMP encryption on the BAR control field using a key negotiated / shared with the receiving STA. In the corresponding encryption process, an AAD can be constructed using the frame control field, duration field, RA field, and / or TA field, which are the preceding portions of the BAR control field in the MPDU format.

[0286] In the case of GCMP, unlike the case of CCMP described above, the MIC value calculated based on the BAR control field is not encrypted.

[0287] Figure 22 This represents another example of the MPDU format of the encryption protocol for block ACK request frames according to this disclosure.

[0288] Reference Figure 22The GCMP MPDU format can be constructed in the following order: Frame Control Field, Duration Field, RA Field, TA Field, GCMP Header Field, Ciphertext, BAR Information Field, MIC Field, and FCS. For example, ciphertext can correspond to the encrypted BAR Control Field. The BAR Information Field can correspond to the unencrypted plaintext. The MIC Field can correspond to the unencrypted plaintext. The corresponding structure is an example, and the scope of this disclosure is not limited thereto.

[0289] In this respect, GCMP header fields may include information related to the block number (PN) (e.g., PN0, PN1, PN2, PN3, PN4, PN5, etc.) and / or information related to the key ID.

[0290] As described above, when applying GCMP, the MIC value can be calculated based on the BAR control field without applying encryption to the MIC value. The BAR control field can be encrypted and included in the corresponding GCMP MPDU format in ciphertext form. Encryption may not be applied to the BAR information field. In other words, apart from the MIC information, GCMP-based encryption can be applied to some fields of the frame body of the block ACK request frame prior to encryption (i.e., the BAR control field and the BAR information field).

[0291] Implementation methods 1-5

[0292] To support protection against block ACK request frames, a format can be constructed that applies CCMP to the (multiple) BAR information fields included in the block ACK request frame.

[0293] The corresponding format can be used to encrypt / decrypt the BAR information field within the block ACK request frame.

[0294] Specifically, the sending STA can perform CCMP encryption on the BAR information field using a key negotiated / shared with the receiving STA. In the corresponding encryption process, the AAD can be constructed using the frame control field, duration field, RA field, and / or TA field, which are the preceding portions of the BAR control field in the MPDU format.

[0295] In the case of CCMP, the MIC value calculated based on the BAR information field can be constructed together with the BAR information field in ciphertext form.

[0296] Figure 23 This represents another example of the MPDU format of the encryption protocol for block ACK request frames according to this disclosure.

[0297] Reference Figure 23The CCMP MPDU format can be constructed in the following order: Frame Control Field, Duration Field, RA Field, TA Field, CCMP Header Field, BAR Control Field, Ciphertext, and FCS. For example, the ciphertext can correspond to the encrypted BAR Information Field and the encrypted MIC Field. The BAR Control Field can correspond to the unencrypted plaintext. The corresponding structure is an example, and the scope of this disclosure is not limited thereto.

[0298] In this respect, CCMP header fields may include information related to block numbers (PNs) (e.g., PN0, PN1, PN2, PN3, PN4, PN5, etc.) and / or information related to key IDs.

[0299] As described above, when CCMP is applied, the MIC value can be calculated based on the BAR information field. The calculated MIC value can then be encrypted along with the BAR information field and included in the CCMP MPDU in ciphertext form. In other words, CCMP-based encryption can be applied to some fields of the frame body of the preceding block ACK request frame (i.e., the BAR control field and the BAR information field), and can also be applied to the MIC information.

[0300] Implementation methods 1-6

[0301] To support protection for block ACK request frames, a format can be constructed that applies GCMP to the BAR information field included in the block ACK request frame.

[0302] The corresponding format can be used to encrypt / decrypt the BAR information field within the block ACK request frame.

[0303] Specifically, the sending STA can perform GCMP encryption on the BAR information field using a key negotiated / shared with the receiving STA. In the corresponding encryption process, the AAD can be constructed using the frame control field, duration field, RA field, and / or TA field, which are the preceding portions of the BAR control field in the MPDU format.

[0304] Unlike the case of CCMP, in the case of GCMP, the MIC value calculated based on the BAR information field is not encrypted.

[0305] Figure 24 This represents another example of the MPDU format of the encryption protocol for block ACK request frames according to this disclosure.

[0306] Reference Figure 24The GCMP MPDU format can be constructed in the following order: Frame Control Field, Duration Field, RA Field, TA Field, GCMP Header Field, BAR Control Field, Ciphertext, MIC Field, and FCS. For example, ciphertext can correspond to encrypted BAR information fields. BAR control fields can correspond to unencrypted plaintext. MIC fields can correspond to unencrypted plaintext. The corresponding structure is an example, and the scope of this disclosure is not limited thereto.

[0307] In this respect, GCMP header fields may include information related to the block number (PN) (e.g., PN0, PN1, PN2, PN3, PN4, PN5, etc.) and / or information related to the key ID.

[0308] As described above, when applying GCMP, the MIC value can be calculated based on the BAR information field without applying encryption to the MIC value. The BAR information field can be encrypted and included in the corresponding GCMP MPDU format in ciphertext form. Encryption may not be applied to the BAR control field. In other words, in addition to the MIC information, GCMP-based encryption can be applied to some fields of the frame body of the block ACK request frame prior to encryption (i.e., the BAR control field and the BAR information field).

[0309] Implementation methods 1-7

[0310] This embodiment relates to a method for signaling whether encryption / protection is supported for block ACK request frames.

[0311] Regarding the block ACK request frame supported by this disclosure, the sending STA and receiving STA may share / exchange information about whether encryption (i.e., CCMP- or GCMP-based encryption) is supported for the block ACK request frame. This information may be shared / exchanged through specific elements (e.g., RSN extension elements (RSNXE)) in the discovery process (e.g., beacon frames, probe response frames, etc.) and / or (re)association process (e.g., (re)association request frames, (re)association response frames, etc.).

[0312] In this regard, the support for the application of CCMP or GCMP to block ACK request frames can be shared by utilizing reserved bits within existing elements (e.g., RSNXE) or by defining new (sub)fields within new elements. For example, a new 1-bit protected block ACK request support (sub)field can be defined, where a value of 1 indicates support for applying CCMP or GCMP to block ACK request frames, and a value of 0 indicates non-support for applying CCMP or GCMP to block ACK request frames.

[0313] When both the transmitting and receiving STAs support encryption and support applying encryption to block ACK request frames, both STAs can perform encryption on the block ACK request frames. Conversely, when both the transmitting and receiving STAs support encryption but do not support applying encryption to block ACK request frames, neither STA may perform encryption on the block ACK request frames. Furthermore, when encrypting block ACK request frames, the same cipher suites negotiated by the transmitting and receiving STAs during the negotiation process (e.g., CCMP-128, CCMP-256, GCMP-128, GCMP-256, etc.) can be used. Alternatively, to encrypt block ACK request frames, the transmitting and receiving STAs may negotiate additional / separate cipher suites for the respective block ACK request frames.

[0314] Alternatively, in existing WLAN systems, for block ACK request frames of the control frame type, the sending and receiving STAs do not perform CCMP or GCMP-based encryption / decryption operations. In this regard, the protected frame subfield of the frame control field within the MAC header is set to be reserved in the case of control frames.

[0315] Conversely, when the BAR control field and / or BAR information field are encrypted / decrypted based on CCMP or GCMP for the block ACK request frame according to various examples of this disclosure, the value of the protected frame subfield within the frame control field of the corresponding block ACK request frame is set to 1. Based on this, the receiving STA can identify that the BAR control field and / or BAR information field within the corresponding block ACK request frame is encrypted by the value of the protected frame subfield. In this respect, when encrypting the block ACK request frame, the cipher suites negotiated by the sending STA and receiving STA during the negotiation process (e.g., CCMP-128, CCMP-256, GCMP-128, GCMP-256, etc.) can be used identically. Alternatively, for encrypting the block ACK request frame, the sending STA and receiving STA may negotiate additional / separate cipher suites for the corresponding block ACK request frame.

[0316] Alternatively or concurrently, information regarding whether encryption (i.e., CCMP- or GCMP-based encryption) is supported for applying to block ACK request frames and / or the construction of a CCMP / GCMP MPDU format according to any of the various examples of this disclosure may be shared between the sending STA and the receiving STA.

[0317] For example, information regarding whether support is performed during the (re)association process, and on what method (e.g., configuration of CCMP / GCMP MPDU format) encryption / decryption is performed, can be indicated as a result of negotiation. Additionally or alternatively, it can also be used to indicate the encryption / decryption mode for block ACK request frames exchanged during data transmission and reception processes following the (re)association process.

[0318] In this regard, to share the relevant information, reserved bits within existing elements (e.g., RSNXE) and / or new (sub)fields within new elements (e.g., protected block ACK request mode (sub)field) can be defined. And / or, when the BAR control field is not encrypted (e.g., refer to...) Figure 23 and Figure 24 A new (sub)field (e.g., a protected block ACK request mode (sub)field) can be defined by utilizing reserved bits within the BAR control field. In this case, the scheme used to encrypt / decrypt the block ACK request frame can use the same cipher suite negotiated by the sending STA and receiving STA during the negotiation process (e.g., CCMP-128, CCMP-256, GCMP-128, GCMP-256, etc.), or an additional / separate cipher suite can be negotiated for the block ACK request frame.

[0319] As described above, the corresponding (sub)field can be included in the beacon frame by the sending STA, or it can be included in the data frame by the receiving STA not only during (re)association but also during data transmission and reception. For example, when the value of the Protected Block ACK Request Mode (sub)field is set to 0, it can mean / indicate that CCMP or GCMP-based encryption is not applied to the corresponding block ACK request frame. Conversely, when the value of the Protected Block ACK Request Mode (sub)field is set to greater than or equal to 1, it can mean / indicate that CCMP or GCMP-based encryption is applied to the block ACK request frame.

[0320] As a specific example, whether to apply CCMP / GCMP encryption based on the value of the corresponding Protected Block ACK Request Mode (Sub) field can be defined as shown in Table 1 below. Table 1 is exemplary, and at least one of the values ​​described in Table 1 can be applied / defined, and specific values ​​can be set / defined differently from the corresponding example.

[0321] [Table 1]

[0322] Alternatively or additionally, the reserved bits of the preceding portion of the key ID information (i.e., the key ID octet) located in the CCMP and / or GCMP headers can be used as a protected block ACK request mode (sub) field, and information regarding whether encryption of the block ACK request frame (i.e., CCMP- or GCMP-based encryption) is supported, as well as information regarding which example among the various examples of this disclosure is used to construct the CCMP / GCMP MPDU format, can be shared. In this case, the scheme used to encrypt / decrypt the block ACK request frame can use the same cipher suite (e.g., CCMP-128, CCMP-256, GCMP-128, GCMP-256, etc.) negotiated by the sending STA and receiving STA during the negotiation process, or additional / separate cipher suites can be negotiated for the block ACK request frame.

[0323] The corresponding (sub)fields can be included in the data frame that is sent from the sending STA to the receiving STA during data transmission and reception processing. For example, when the value of the Protected Block ACK Request Mode (sub)field is set to 0, it may mean / indicate that CCMP or GCMP-based encryption is not applied to the corresponding block ACK request frame. Conversely, when the value of the Protected Block ACK Request Mode (sub)field is set to greater than or equal to 1, it may mean / indicate that CCMP or GCMP-based encryption is applied to the block ACK request frame.

[0324] As a specific example, whether CCMP / GCMP encryption is applied based on the value of the corresponding Protected Block ACK Request Mode (Sub) field can be defined as shown in Table 2 below. Table 2 is exemplary, and at least one of the values ​​described in Table 2 can be applied / defined, and specific values ​​can be set / defined differently from the corresponding examples.

[0325] [Table 2]

[0326] Implementation Method 2

[0327] This embodiment relates to a method for generating a MIC for CCMP / GCMP transmission / reception in connection with applying encryption to the aforementioned block ACK request frame.

[0328] In the case of a block ACK request frame, the type (or variant) of the block ACK request frame to be sent and received can be indicated by the value of the BAR type subfield within the BAR control field. Based on the indicated value, the receiving STA can confirm whether the corresponding block ACK request frame is a single-addressed frame or a group-addressed frame.

[0329] In this respect, when CCMP or GCMP is applied to a block ACK request frame, the key used to calculate / set the MIC value can be used differently depending on whether it is a single addressing frame or a group addressing frame.

[0330] For example, in the case of individually addressed data frames, the MIC value can be calculated using a TK based on the PTK generated identically between the transmitting and receiving STAs. On the other hand, in the case of group-addressed data frames, the MIC value can be calculated using a TK based on the GTK shared by the transmitting and receiving STAs.

[0331] In the case of existing CCMP / GCMP (e.g., CCMP / GCMP applied to data frames / management frames), IGTK- or BIGTK-based BIPs can be used, but it is not possible to use IGTK- or BIGTK-based CCMP and GCMP. Instead, in this disclosure, it is assumed that PTK / GTK / IGTK / BIGTK-based CCMP and / or GCMP can be used.

[0332] The key usage scheme for calculating and verifying the MIC value for individually addressed block ACK request frames and / or group-addressed block ACK request frames will be described in detail below.

[0333] First, in the case of a separately addressed block ACK request frame, the MIC value can be calculated / verified as follows.

[0334] For example, the sending STA and the receiving STA can calculate the MIC value using a TK based on the PTK that is generated identically between them during the four-way handshake process. For instance, the sending STA and the receiving STA can identically use the PTK generated with respect to the protection of data frames during the four-way handshake process to apply CCMP / GCMP to block ACK frames. That is, the sending STA and the receiving STA can calculate the MIC value for block ACK request frames using a TK based on the PTK, which is generated relative to the protection of unicast data frames during the four-way handshake process.

[0335] As another example, the sending STA and receiving STA can calculate the MIC value for the block ACK request frame using a TK based on a new key (i.e., a key that is distinct from the key (PTK) used for data frames), which is generated / negotiated / shared in the same way with regard to the protection of the corresponding block ACK request frame during the 4-way handshake process.

[0336] The new key can be a key that distinguishes multiple STAs, or it can be a public key for multiple STAs. For example, the sending STA can generate and share different new keys for the first receiving STA and the second receiving STA. Alternatively, the sending STA can generate and share the same new key for the first receiving STA and the second receiving STA. Here, the new key data element (KDE) generated by the sending STA and the new key data element (KDE) used for the corresponding new key can include information related to the new key and the cipher suites that can be used with the corresponding key, and can be shared with the receiving STA. For example, the new key can be called a block ACK request PTK (BARPTK) or a group block ACK request PTK (BARPTK).

[0337] When the receiving STA and the transmitting STA generate or share a new key for protecting the block ACK request frame, MIC verification can be performed using the generated / shared key for the received block ACK request frame. When the receiving STA and the transmitting STA do not generate or share a new key for protecting the block ACK request frame, MIC verification can be performed using the key used for encrypting / decrypting unicast data frames (e.g., PTK).

[0338] Next, in the case of a group-addressed block ACK request frame, the MIC value can be calculated / verified as follows.

[0339] For example, the sending STA can generate an IGTK or BIGTK during the four-way handshake process and share the IGTK or BIGTK with the receiving STA. The sending STA and the receiving STA can calculate the MIC value for the block ACK request frame by using the TK based on the corresponding IGTK or the corresponding BIGTK.

[0340] As another example, the sending STA can generate a GTK during the four-way handshake process and share that GTK with the receiving STA, and the sending and receiving STAs can calculate the MIC value for the block ACK request frame by using the TK based on the corresponding GTK.

[0341] As another example, the sending STA can generate a new GTK (i.e., a key distinct from the existing IGTK / BIGTK / GTK) for a group-addressed block ACK request frame during the four-way handshake process, and share this new GTK with the receiving STA. The sending and receiving STAs can calculate the MIC value using a TK based on the corresponding new GTK. Here, the new GTK can be called the Block ACK Request Broadcast GTK (BARGTK), and the sending STA can share the same BARGTK value with the receiving STA. In other words, the AP can generate the same BARGTK and share it with the STAs associated with it. Furthermore, information about the BARGTK and related cipher suites that can use the corresponding BARGTK can be shared between the sending and receiving STAs through a new KDE (e.g., BARGTKKDE) for the corresponding BARGTK.

[0342] When the receiving STA receives a key (e.g., BARGTK) from the sending STA for protecting the block ACK request frame, it can perform MIC verification on the block ACK request frame based on the corresponding key. Otherwise, the receiving STA can perform MIC verification on the block ACK request frame based on a key (e.g., GTK, IGTK, or BIGTK) of a broadcast frame previously shared with the sending STA.

[0343] Implementation Method 3

[0344] This embodiment relates to a detailed method for performing protection (i.e., encryption and integrity verification) on a block ACK request frame based on the block ACK request frame construction according to this disclosure.

[0345] First, when the block ACK request frame is a group-addressed block ACK request frame, the block ACK request frame can be constructed as follows to derive the MIC value.

[0346] For example, the block ACK request frame construction described in Implementation 1-1 (for example, refer to...) Figure 19 In the case of ), the sending STA and / or receiving STA can perform encryption / decryption via CCMP and derive the MIC values ​​for the BAR control field and BAR information field using GTK, IGTK, BIGTK, or BARGTK.

[0347] As another example, the block ACK request frame construction described in embodiments 1-2 (for example, refer to...) Figure 20 In the case of ), the sending STA and / or receiving STA can perform encryption / decryption via GCMP and derive the MIC values ​​for the BAR control field and BAR information field using GTK, IGTK, BIGTK, or BARGTK.

[0348] As another example, the block ACK request frame construction described in embodiments 1-3 (for example, refer to...) Figure 21 In the case of ), the sending STA and / or receiving STA can perform encryption / decryption via CCMP and derive the MIC value for the BAR control field using GTK, IGTK, BIGTK, or BARGTK.

[0349] As another example, the block ACK request frame construction described in embodiments 1-4 (for example, refer to...) Figure 22 In the case of ), the sending STA and / or receiving STA can perform encryption / decryption via GCMP and derive the MIC value for the BAR control field using GTK, IGTK, BIGTK, or BARGTK.

[0350] As another example, the block ACK request frame construction described in embodiments 1-5 (for example, refer to...) Figure 23 In the case of ), the sending STA and / or receiving STA can perform encryption / decryption via CCMP and derive the MIC value for the BAR information field using GTK, IGTK, BIGTK, or BARGTK.

[0351] As another example, the block ACK request frame construction described in embodiments 1-6 (for example, refer to...) Figure 24 In the case of ), the sending STA and / or receiving STA can perform encryption / decryption via GCMP and derive the MIC value for the BAR information field using GTK, IGTK, BIGTK, or BARGTK.

[0352] Next, when the block ACK request frame is a separately addressed block ACK request frame, the block ACK request frame can be constructed as follows to derive the MIC value.

[0353] For example, the block ACK request frame construction described in Implementation 1-1 (for example, refer to...) Figure 19 In the case of ), the sending STA and / or receiving STA can perform encryption / decryption via CCMP and derive the MIC values ​​for the BAR control field and BAR information field by using the aforementioned PTK, or BAPTK, or group BARPTK.

[0354] As another example, the block ACK request frame construction described in embodiments 1-2 (for example, refer to...) Figure 20 In the case of ), the sending STA and / or receiving STA can perform encryption / decryption via GCMP and derive the MIC values ​​for the BAR control field and BAR information field by using the aforementioned PTK or BARPTK or group BARPTK.

[0355] As another example, the block ACK request frame construction described in embodiments 1-3 (for example, refer to...) Figure 21 In the case of ), the sending STA and / or receiving STA can perform encryption / decryption via CCMP and derive the MIC value for the BAR control field by using PTK or BARPTK (or group BARPTK).

[0356] As another example, in the case of the block ACK request frame construction described in embodiments 1-4 (e.g., refer to 22), the sending STA and / or receiving STA can perform encryption / decryption via GCMP and derive the MIC value for the BAR control field by using PTK or BARPTK (or group BARPTK).

[0357] As another example, the block ACK request frame construction described in embodiments 1-5 (for example, refer to...) Figure 23 In the case of ), the sending STA and / or receiving STA can perform encryption / decryption via CCMP and derive the MIC value for the BAR information field by using PTK or BARPTK (or group BARPTK).

[0358] As another example, the block ACK request frame construction described in embodiments 1-6 (for example, refer to...) Figure 24 In the case of ), the sending STA and / or receiving STA can perform encryption / decryption via GCMP and derive the MIC value for the BAR information field by using PTK or BARPTK (or group BARPTK).

[0359] Based on the various examples in this disclosure, protection of block ACK request frames can be performed as follows.

[0360] For example, as described below, assume that the sending STA and receiving STA support the use of block ACK request frames on CCMP or GCMP through the Protected Block ACK Request Support (sub) field, and / or share the construction scheme of the CCMP / GCMP MPDU format of the block ACK request frame through the Protected Block ACK Request Mode (sub) field.

[0361] The receiving STA can construct an AAD for the block ACK request frame based on information from the MAC header of the MPDU received from the sending STA (e.g., frame control field, duration field, RA field, TA field, etc.). The receiving STA can then use the appropriate AAD to decrypt the MSDU.

[0362] The receiving STA can obtain the MPDU in plaintext form and the MIC value based on the corresponding MPDU, which is the result of decryption using AAD and CCMP constructed by itself for a block ACK request frame. In this case, the receiving STA can derive the MIC value by performing the encryption process for the corresponding MPDU in the same manner as the sending STA.

[0363] The receiving STA can compare the derived MIC value with the MIC value sent by the sending STA (e.g., MIC information included in CCMP MPDU or GCMP MPDU formats). When the two MIC values ​​are the same, the receiving STA can follow the information in the obtained plaintext MPDU. Conversely, when the two MIC values ​​are different, the receiving STA can identify that at least one piece of information in the obtained plaintext MPDU has been altered by a third STA (e.g., an attacking STA) or has been corrupted during transmission and reception, and can discard the corresponding MPDU.

[0364] In the case of CCMP where the MIC is encrypted, the receiving STA can perform integrity checks using the MIC, which is generated / computed based on the plaintext derived by decrypting the MPDU. In the case of GCMP where the MIC is not encrypted, the receiving STA can first perform integrity checks using the value of the MIC field of the MPDU, and can decrypt the MPDU if the MIC value matches.

[0365] According to embodiments of this disclosure, the operation of the STA that supports / executes protection against block ACK request frames can be as follows: Figure 25 and Figure 26 As shown.

[0366] Figure 25 An example of a transmission STA operation supporting protection for a block ACK request frame, according to this disclosure, is illustrated.

[0367] Reference Figure 25 The sending STA can share information with the receiving STA regarding whether protection (e.g., confidentiality and integrity checks) is supported for block ACK request frames, S2510.

[0368] In this scenario, when both the sending STA and the receiving STA apply security to the block ACK request frame, the sending STA can generate and share a key (e.g., PTK / GTK / BARPTK / BARGTK) S2520 for confidentiality and integrity verification of the block ACK request frame. At this point, the sending STA and the receiving STA can generate / negotiate / share the same key information through a key generation process, or the key information generated by the sending STA can be delivered to the receiving STA.

[0369] Based on the corresponding key, the transmitting STA can apply CCMP or GCMP to the configured block ACK request frame S2530. At this point, the transmitting STA can derive the MIC value for the block ACK request frame using a key previously shared with the receiving STA.

[0370] The STA can send a block ACK request frame S2540 that includes the result value / information for the CCMP or GCMP application.

[0371] Regarding the above process, the sending STA can share / negotiate with the receiving STA in advance what form of CCMP / GCMP MPDU format information to configure in the block ACK request frame it is sending, or it can include the corresponding information in the block ACK request frame and send it.

[0372] Figure 26 The operation of a receiving STA supporting protection against block ACK request frames is illustrated according to this disclosure.

[0373] Reference Figure 26 The receiving STA can share information with the sending STA regarding whether protection (e.g., confidentiality and integrity checks) is supported for block ACK request frames, S2610.

[0374] In this case, when the receiving STA shares the key used for confidentiality and integrity verification of the block ACK request frame with the sending STA, the receiving STA can assume that the protection method is applied to the block ACK request frame S2620 sent by the sending STA.

[0375] In this respect, the sending STA and the receiving STA can generate / negotiate / share the same key information (e.g., PTK / GTK / BARPTK / BARGTK, etc.) through a key generation process, or the key information generated by the sending STA can be delivered to the receiving STA.

[0376] For example, the receiving STA can receive a block ACK request frame sent from the sending STA and identify whether it is applied to CCMP or GCMP based on a pre-shared key and / or information related to the configuration method of the CCMP / GCMP MPDU format in the block ACK request frame.

[0377] Based on this, when a block ACK request frame is received, the receiving STA can perform decryption S2630 by applying CCMP or GCMP to the block ACK request frame based on a pre-shared / generated / negotiated key (e.g., PTK / GTK / BARPTK / BARGTK, etc.).

[0378] Subsequently, the receiving STA can perform integrity verification S2640 by comparing the MIC value derived from the decrypted block ACK request frame with the MIC value sent by the sending STA (i.e., the MIC information / value included in the block ACK request frame).

[0379] Protocols such as CCMP / GCMP used in existing WLAN systems may not provide protection for control frames such as block ACK request frames. In this disclosure, a new method for sending or receiving protected control frames can be provided by defining protocols such as CCMP / GCMP for control frames such as block ACK request frames.

[0380] The above embodiments combine the elements and features of this disclosure in a predetermined form. Unless otherwise expressly stated, each element or feature should be considered optional. Each element or feature may be implemented without being combined with other elements or features. Furthermore, embodiments of this disclosure may include combinations of some elements and / or features. The order of operations described in embodiments of this disclosure may be changed. Some elements or features of one embodiment may be included in other embodiments, or may be replaced by corresponding elements or features of other embodiments. Obviously, embodiments may include claims that are not explicitly referenced in the claims, or may be included as new claims after the application has been amended.

[0381] It will be apparent to those skilled in the art that this disclosure may be implemented in other specific forms without departing from its essential characteristics. Therefore, the above detailed description should not be construed as restrictive in every respect, but rather as illustrative. The scope of this disclosure should be determined by a reasonable interpretation of the appended claims, and all variations within the equivalent scope of this disclosure are included within its scope.

[0382] The scope of this disclosure includes software or machine-executable commands (e.g., operating systems, applications, firmware, programs, etc.) that operate in a device or computer according to methods of various embodiments, as well as non-transitory computer-readable media that cause software or commands to be stored and executable in a device or computer. Commands that can be used to program a processing system to perform the features described in this disclosure can be stored in a storage medium or a computer-readable storage medium, and the features described in this disclosure can be implemented by using a computer program product including such a storage medium. The storage medium may include, but is not limited to, high-speed random access memory, such as DRAM, SRAM, DDR RAM, or other random access solid-state storage devices, and may include non-volatile memory, such as one or more disk storage devices, optical disk storage devices, flash memory devices, or other non-volatile solid-state storage devices. The memory may optionally include one or more storage devices located remotely from the processor. The memory, or alternatively, the non-volatile memory devices in the memory include non-transitory computer-readable storage media. The features described in this disclosure can be stored in any machine-readable medium to control the hardware of a processing system and can be integrated into software and / or firmware that allows the processing system to interact with other mechanisms using the results of embodiments of this disclosure. Such software or firmware may include, but is not limited to, application code, device drivers, operating systems, and execution environments / containers.

[0383] Industrial applicability

[0384] The method presented in this disclosure is primarily described based on examples applied to IEEE 802.11-based systems, but can be applied to various WLAN or wireless communication systems other than IEEE 802.11-based systems.

Claims

1. A method, the method comprising: The first station (STA) generates a block acknowledgment (ACK) request frame based on the encryption protocol; as well as The first STA sends the block ACK request frame to the second STA. The block ACK request frame includes encrypted information based on the encryption protocol, and The encrypted information is based on the block ACK request control field or block ACK request information field in the frame body of the block ACK request frame.

2. The method according to claim 1, wherein, Encryption of the block ACK request frame is performed based on key information related to the protection of the block ACK request frame.

3. The method according to claim 1, wherein, The block ACK request frame includes Message Integrity Code (MIC) information calculated based on key information related to the protection of the block ACK request frame.

4. The method according to claim 1, wherein, Based on the encryption protocol corresponding to the Counter Mode Protocol with Cipher Block Chaining Message Authentication Code (CCMP), CCMP-128 or CCMP-256 is used as a cipher suite for CCMP, and Based on the fact that the specific encryption protocol corresponds to the Galois / Counter Mode Protocol GCMP, GCMP-128 or GCMP-256 is used as a cipher suite against the GCMP.

5. The method according to claim 1, wherein, Since the encryption protocol corresponds to CCMP, the encrypted information is also based on MIC information related to the protection of the block ACK request frame.

6. The method according to claim 1, wherein, Based on the encryption protocol corresponding to CCMP, and the encrypted information being based on the block ACK request control field, the encrypted information includes multiple non-contiguous encrypted fields. The encryption protocol corresponds to CCMP, and the encrypted information is based on the block ACK request information field, which includes multiple consecutive encrypted fields.

7. The method according to claim 1, wherein, Based on the encryption protocol corresponding to GCMP, the encrypted information includes a single encrypted field.

8. The method according to claim 1, wherein, The block ACK request frame includes an encryption protocol header, which includes a first field for the key identifier ID and a second field for the block number.

9. The method according to claim 8, wherein, The encryption protocol header also includes information regarding at least one of the following: whether protection is supported for the block ACK request frame or the MAC Protocol Data Unit (MPDU) format within the block ACK request frame according to the encryption protocol.

10. The method according to claim 1, wherein, Between the first STA and the second STA, information indicating whether protection is supported for the block ACK request frame is exchanged.

11. The method according to claim 10, wherein, The information indicating whether the protection for the block ACK request frame is supported is exchanged through at least one of a beacon frame, probe request frame, probe response frame, association request frame, association response frame, reassociation request frame, reassociation response frame, or the block ACK request frame.

12. The method according to claim 1, wherein, Based on the encryption protocol applied to the block ACK request frame, the protected frame subfield, including the frame control field in the block ACK request frame, is set to a predefined specific value.

13. The method according to claim 1, wherein, Between the first STA and the second STA, information in MPDU format according to the encryption protocol is exchanged.

14. The method according to claim 13, wherein, Information in the MPDU format according to the encryption protocol is included in at least one of an association request frame, an association response frame, a reassociation request frame, a reassociation response frame, a beacon frame, a data frame, or the block ACK request frame.

15. The method according to claim 1, wherein, Based on the fact that the block ACK request frame corresponds to a separately addressed control frame, the key information related to the protection of the block ACK request frame is based on the pairwise transient key PTK for the first STA and the second STA, and The key information related to the protection of the block ACK request frame is based on the group addressing control frame corresponding to the block ACK request frame, and is based on the group temporary key GTK for the first STA and the second STA.

16. The method according to claim 1, wherein, The block ACK request frame includes information related to a request for a block ACK for data to be received by the second STA, and The key information associated with the protection of the block ACK request frame is different from the key information associated with the protection of the data.

17. An apparatus comprising: One or more transceivers; as well as One or more processors, said one or more processors being connected to said one or more transceivers, Wherein, the one or more processors are configured as follows: The first station (STA) generates a block acknowledgment (ACK) request frame based on the encryption protocol; and The first STA sends the block ACK request frame to the second STA. The block ACK request frame includes encrypted information based on the encryption protocol, and The encrypted information is based on the block ACK request control field or block ACK request information field in the frame body of the block ACK request frame.

18. A method, the method comprising: The second STA receives a block acknowledgment (ACK) request frame based on the encryption protocol from the first STA; as well as The second STA performs decryption and integrity verification on the block ACK request frame. The block ACK request frame includes encrypted information based on the encryption protocol, and The encrypted information is based on the block ACK request control field or block ACK request information field in the frame body of the block ACK request frame.

19. An apparatus comprising: One or more transceivers; as well as One or more processors, said one or more processors being connected to said one or more transceivers, Wherein, the one or more processors are configured as follows: The second STA receives a block acknowledgment (ACK) request frame based on an encryption protocol from the first STA; and The second STA performs decryption and integrity verification on the block ACK request frame. The block ACK request frame includes encrypted information based on the encryption protocol, and The encrypted information is based on the block ACK request control field or block ACK request information field in the frame body of the block ACK request frame.

20. A processing apparatus, the processing apparatus comprising: One or more processors; as well as One or more computer memories, operatively connected to one or more processors, and storing instructions that, based on execution by one or more processors, perform the method according to any one of claims 1 to 16.

21. One or more non-transitory computer-readable media storing one or more instructions, which are controlled by execution by one or more processors to perform the method according to any one of claims 1 to 16.

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