Method and device 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. A method according to one embodiment of the present disclosure may include: receiving a protected block ACK request frame from a second STA based on a specific protocol by a first station (STA); generating an AAD based on the block ACK request frame by the first STA; and performing one or more of decoding or integrity checks on the block ACK request frame by the first STA based on the AAD. The AAD may be based on one or more fields included in the MAC header of the block ACK request frame, or based on one or more subfields included in the MAC header and one or more subfields included in the block ACK request control field or block ACK request information field of the block ACK request frame.

Description

Technology Field

[0001] The present disclosure relates to a method and apparatus for transmitting or receiving a protected control frame 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 reduce latency. Among wireless LAN technologies, the IEEE (Institute of Electrical and Electronics Engineers) 802.11 series of standards can be referred to as Wi-Fi. For example, technologies recently introduced to wireless LANs include enhancements for Very High-Throughput (VHT) in the 802.11ac standard and enhancements for High Efficiency (HE) in the IEEE 802.11ax standard.

[0003] To provide an improved wireless communication environment, advanced technologies for Extremely High Throughput (EHT) are being discussed. For example, technologies for Multiple Input Multiple Output (MIMO) supporting increased bandwidth, efficient utilization of multiple bands, and increased spatial streams, as well as technologies for multiple access points (AP) coordination, are being researched. In particular, various technologies are being studied to support traffic with low latency or real-time characteristics. Furthermore, new technologies to support ultra-high reliability (UHR), including improvements or extensions of EHT technology, are being discussed. The problem to be solved

[0004] The technical problem of the present disclosure is to provide a method and apparatus for transmitting or receiving a protected control frame in a wireless LAN system.

[0005] The technical problem of the present disclosure is to provide a method and apparatus that support encryption / decryption / integrity check based on additional authentication data (AAD) for a block ACK (acknowledgement) request frame in a wireless LAN system.

[0006] The technical problems to be solved in this disclosure are not limited to those mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art to which this disclosure belongs from the description below. means of solving the problem

[0007] A method according to one aspect of the present disclosure may include: receiving a block ACK (acknowledgement) request frame protected based on a specific protocol from a second STA by a first station (STA); generating additional authentication data (AAD) based on the block ACK request frame by the first STA; and performing one or more of decoding or integrity checks on the block ACK request frame by the first STA based on the AAD. Herein, the AAD may be based on one or more fields included in a medium access control (MAC) header of the block ACK request frame, or based on one or more subfields included in the MAC header and one or more subfields included in the block ACK request control field or block ACK request information field of the block ACK request frame.

[0008] A method according to a further aspect of the present disclosure may include: generating additional authentication data (AAD) for a block ACK (acknowledgement) request frame based on a specific protocol by a second station (STA); and transmitting a block ACK request frame protected based on the AAD to a first STA by the second STA. Herein, the AAD may be based on one or more fields included in a medium access control (MAC) header of the block ACK request frame, or one or more subfields included in the MAC header, and one or more subfields included in a block ACK request control field or a block ACK request information field of the block ACK request frame. Effects of the invention

[0009] According to the present disclosure, a method and apparatus for transmitting or receiving a protected control frame in a wireless LAN system may be provided.

[0010] According to the present disclosure, a method and apparatus may be provided for supporting encryption / decryption / integrity check based on additional authentication data (AAD) for a block ACK (acknowledgement) request frame in a wireless LAN system.

[0011] The effects obtainable from the present disclosure are not limited to those mentioned above, and other unmentioned effects will be clearly understood by those skilled in the art to which the present disclosure belongs from the description below. Brief explanation of the drawing

[0012] The accompanying drawings, which are included as part of the detailed description to aid in understanding the present disclosure, provide embodiments of the present disclosure and explain the technical features of the present disclosure together with the detailed description. FIG. 1 illustrates a block diagram of a wireless communication device according to one embodiment of the present disclosure. FIG. 2 is a drawing showing an exemplary structure of a wireless LAN system to which the present disclosure can be applied. FIG. 3 is a diagram illustrating a link setup process to which the present disclosure can be applied. FIG. 4 is a drawing illustrating a backoff process to which the present disclosure may be applied. FIG. 5 is a diagram illustrating a CSMA / CA-based frame transmission operation to which the present disclosure may be applied. FIG. 6 is a drawing for illustrating an example of a frame structure used in a wireless LAN system to which the present disclosure may be applied. FIG. 7 is a drawing illustrating examples of PPDUs defined in the IEEE 802.11 standard to which the present disclosure may be applied. FIG. 8 is a diagram illustrating a 4-way handshake procedure to which the present disclosure may be applied. FIG. 9 is a drawing showing an example of an expanded CCMP MPDU to which the present disclosure can be applied. FIG. 10 shows a CCMP encapsulation block diagram to which the present disclosure can be applied. Figure 11 shows an example of the format of a conventional AAD. FIG. 12 shows a CCMP decapsulation block diagram to which the present disclosure can be applied. FIG. 13 is a drawing showing an example of an expanded GCMP MPDU to which the present disclosure can be applied. FIG. 14 shows a GCMP encapsulation block diagram to which the present disclosure can be applied. FIG. 15 shows a GCMP decapsulation block diagram to which the present disclosure can be applied. FIG. 16 is a diagram showing an exemplary format of a block-ACK request frame to which the present disclosure can be applied. FIG. 17 is a drawing for explaining the operation of a first STA according to the present disclosure. FIG. 18 is a drawing for explaining the operation of a second STA according to the present disclosure. FIG. 19 shows examples of AAD configurations for protecting block ACK request frames according to embodiments of the present disclosure. FIG. 20 illustrates the operation of a transmitting STA that supports protection for a block ACK request frame according to the present disclosure. FIG. 21 illustrates the operation of a receiving STA that supports protection for a block ACK request frame according to the present disclosure. Specific details for implementing the invention

[0013] Hereinafter, preferred embodiments according to the present disclosure will be described in detail with reference to the accompanying drawings. The detailed description disclosed below, together with the accompanying drawings, is intended to describe exemplary embodiments of the present disclosure and is not intended to represent the only embodiment in which the present disclosure may be practiced. The following detailed description includes specific details to provide a complete understanding of the present disclosure. However, those skilled in the art will know that the present disclosure may be practiced without such specific details.

[0014] In some cases, to avoid obscuring the concept of the present disclosure, known structures and devices may be omitted or illustrated in the form of a block diagram focusing on the core functions of each structure and device.

[0015] In the present disclosure, when a component is described as being “connected,” “combined,” or “joined” with another component, this may include not only a direct connection but also an indirect connection in which another component exists between them. Furthermore, in the present disclosure, the terms “comprising” or “having” specify the presence of the mentioned features, steps, actions, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, actions, elements, components, and / or groups thereof.

[0016] In the present disclosure, terms such as "first," "second," etc. are used solely for the purpose of distinguishing one component from another and are not used to limit the components, nor do they limit the order or importance of the components unless specifically stated otherwise. Accordingly, within the scope of the present disclosure, a first component in one embodiment may be referred to as a second component in another embodiment, and likewise, a second component in one embodiment may be referred to as a first component in another embodiment.

[0017] The terms used in this disclosure are for the description of specific embodiments and are not intended to limit the claims. As used in the description of embodiments and in 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 any one of the related enumerated items, or refers to and includes any and all possible combinations of two or more of them. Additionally, the " / " between words in this disclosure has the same meaning as "and / or" unless otherwise noted.

[0018] The embodiments of the present disclosure may be applied to various wireless communication systems. For example, the embodiments of the present disclosure may be applied to wireless LAN systems. For example, the embodiments of the present disclosure may be applied to wireless LANs based on IEEE 802.11a / g / n / ac / ax / be standards. Furthermore, the embodiments of the present disclosure may be applied to wireless LANs based on newly proposed IEEE 802.11bn (or UHR) standards. Additionally, the embodiments of the present disclosure may be applied to wireless LANs based on next-generation standards following IEEE 802.11bn. Furthermore, the embodiments of the present disclosure may be applied to cellular wireless communication systems. For example, they may be applied to cellular wireless communication systems based on LTE (Long Term Evolution) series technologies and 5G NR (New Radio) series technologies of 3GPP (3rd Generation Partnership Project) standards.

[0019] The following describes the technical features to which the examples of the present disclosure may be applied.

[0020] FIG. 1 illustrates a block diagram of a wireless communication device according to one embodiment of the present disclosure.

[0021] The first device (100) and the second device (200) exemplified in FIG. 1 may be replaced with various terms such as terminal, wireless device, WTRU (Wireless Transmit Receive Unit), UE (User Equipment), MS (Mobile Station), UT (user terminal), MSS (Mobile Subscriber Station), MSS (Mobile Subscriber Unit), SS (Subscriber Station), AMS (Advanced Mobile Station), WT (Wireless terminal), or simply user. Additionally, the first device (100) and the second device (200) may be replaced with various terms such as access point (AP), base station (BS), fixed station, Node B, base transceiver system (BTS), network, artificial intelligence (AI) system, road side unit (RSU), repeater, router, relay, gateway, etc.

[0022] The device (100, 200) exemplified in FIG. 1 may be referred to as a station (STA). For example, the device (100, 200) exemplified in FIG. 1 may be referred to by various terms such as a transmitting device, a receiving device, a transmitting STA, or a receiving STA. For example, the STA (110, 200) may perform the role of an access point (AP) or a non-AP. That is, in the present disclosure, the STA (110, 200) may perform the functions of an AP and / or a non-AP. If the STA (110, 200) performs the AP function, it may simply be referred to as an AP, and if the STA (110, 200) performs the non-AP function, it may simply be referred to as a STA. Additionally, in the present disclosure, the AP may also be indicated as an AP STA.

[0023] Referring to FIG. 1, the first device (100) and the second device (200) can transmit and receive wireless signals through various wireless LAN technologies (e.g., IEEE 802.11 series). The first device (100) and the second device (200) may include interfaces for the medium access control (MAC) layer and the physical layer (PHY) that comply with the specifications of the IEEE 802.11 standard.

[0024] In addition, the first device (100) and the second device (200) may additionally support various communication standards other than wireless LAN technology (e.g., 3GPP LTE series, 5G NR series standards, etc.). In addition, the device of the present disclosure may be implemented as various devices such as mobile phones, vehicles, personal computers, AR (Augmented Reality) equipment, VR (Virtual Reality) equipment, etc. Furthermore, the STA of the present specification may support various communication services such as voice calls, video calls, data communication, autonomous driving, MTC (Machine-Type Communication), M2M (Machine-to-Machine), D2D (Device-to-Device), and IoT (Internet-of-Things).

[0025] The first device (100) includes 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 processor (102) controls the memory (104) and / or transceivers (106) and may be configured to implement the descriptions, functions, procedures, proposals, methods and / or sequences of operation disclosed in this disclosure. For example, the processor (102) may process information within the memory (104) to generate a first information / signal and then transmit a wireless signal containing the first information / signal through the transceiver (106). Additionally, the processor (102) may receive a wireless signal containing a second information / signal through the transceiver (106) and then store information obtained from the signal processing of the second information / signal in the memory (104). Memory (104) may be connected to the processor (102) and may store various information related to the operation of the processor (102). For example, memory (104) may store software code including instructions for performing some or all of the processes controlled by the processor (102) or for performing the descriptions, functions, procedures, proposals, methods, and / or sequences of operation disclosed in this disclosure. Here, the 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). A transceiver (106) may be connected to the processor (102) and may transmit and / or receive wireless signals through one or more antennas (108). The transceiver (106) may include a transmitter and / or receiver. The transceiver (106) may be combined with an RF (Radio Frequency) unit. In the present disclosure, the device may refer to a communication modem / circuit / chip.

[0026] The second device (200) includes 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 processor (202) controls the memory (204) and / or transceivers (206) and may be configured to implement the descriptions, functions, procedures, proposals, methods and / or sequences of operation disclosed in this disclosure. For example, the processor (202) may process information within the memory (204) to generate a third information / signal and then transmit a wireless signal containing the third information / signal through the transceiver (206). Additionally, the processor (202) may receive a wireless signal containing a fourth information / signal through the transceiver (206) and then store information obtained from the signal processing of the fourth information / signal in the memory (204). The memory (204) may be connected to the processor (202) and may store various information related to the operation of the processor (202). For example, the memory (204) may store software code containing instructions for performing some or all of the processes controlled by the processor (202) or for performing the descriptions, functions, procedures, proposals, methods, and / or sequences of operation disclosed in this disclosure. Here, the processor (202) and the memory (204) may be part of a communication modem / circuit / chip designed to implement wireless LAN technology (e.g., IEEE 802.11 series). The transceiver (206) may be connected to the processor (202) and may transmit and / or receive wireless signals through one or more antennas (208). The transceiver (206) may include a transmitter and / or receiver. The transceiver (206) may be used in combination with an RF unit. In the present disclosure, the device may refer to a communication modem / circuit / chip.

[0027] Hereinafter, hardware elements of the device (100, 200) will be described in more detail. Although not limited thereto, one or more protocol layers may be implemented by one or more processors (102, 202). For example, one or more processors (102, 202) may implement one or more layers (e.g., functional layers such as PHY, MAC). One or more processors (102, 202) may generate one or more Protocol Data Units (PDUs) and / or Service Data Units (SDUs) according to the descriptions, functions, procedures, proposals, methods, and / or flowcharts of operation disclosed in this disclosure. One or more processors (102, 202) may generate messages, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and / or flowcharts of operation disclosed in this disclosure. One or more processors (102, 202) may generate a signal (e.g., a baseband signal) including a PDU, SDU, message, control information, data, or information according to the functions, procedures, proposals, and / or methods disclosed in this disclosure and provide it to one or more transceivers (106, 206). One or more processors (102, 202) may receive a signal (e.g., a baseband signal) from one or more transceivers (106, 206) and may obtain a PDU, SDU, message, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and / or flowcharts disclosed in this disclosure.

[0028] One or more processors (102, 202) may be referred to as a controller, microcontroller, microprocessor, or microcomputer. One or more processors (102, 202) may be implemented by hardware, firmware, software, or a combination thereof. For example, one or more Application Specific Integrated Circuits (ASICs), one or more Digital Signal Processors (DSPs), one or more Digital Signal Processing Devices (DSPDs), one or more Programmable Logic Devices (PLDs), or one or more Field Programmable Gate Arrays (FPGAs) may be included in one or more processors (102, 202). The descriptions, functions, procedures, proposals, methods, and / or flowcharts disclosed in this disclosure may be implemented using firmware or software, and the firmware or software may be implemented to include modules, procedures, functions, etc. Firmware or software configured to perform the descriptions, functions, procedures, proposals, methods, and / or operation sequences disclosed in this disclosure may be included in one or more processors (102, 202) or stored in one or more memories (104, 204) and driven by one or more processors (102, 202). The descriptions, functions, procedures, proposals, methods, and / or operation sequences disclosed in this disclosure may be implemented using firmware or software in the form of code, instructions, and / or sets of instructions.

[0029] One or more memories (104, 204) may be connected to one or more processors (102, 202) and may store various forms of data, signals, messages, information, programs, codes, instructions, and / or commands. One or more memories (104, 204) may be composed of ROM, RAM, EPROM, flash memory, hard drive, registers, cache memory, computer read storage media, and / or combinations thereof. One or more memories (104, 204) may be located inside and / or outside of one or more processors (102, 202). Additionally, one or more memories (104, 204) may be connected to one or more processors (102, 202) through various technologies such as wired or wireless connections.

[0030] One or more transceivers (106, 206) may transmit user data, control information, wireless signals / channels, etc., as mentioned in the methods and / or operation flowcharts, etc., of the present disclosure to one or more other devices. One or more transceivers (106, 206) may receive user data, control information, wireless signals / channels, etc., as mentioned in the descriptions, functions, procedures, proposals, methods and / or operation flowcharts, etc., disclosed in the present disclosure from one or more other devices. For example, one or more transceivers (106, 206) may be connected to one or more processors (102, 202) and may transmit and receive wireless signals. For example, one or more processors (102, 202) may 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) may 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., as described in the descriptions, functions, procedures, proposals, methods, and / or flowcharts of operation disclosed in this disclosure through one or more antennas (108, 208). In this disclosure, one or more antennas may be a plurality of physical antennas or a plurality of logical antennas (e.g., antenna ports). One or more transceivers (106, 206) can convert the received wireless signal / channel, etc. from an RF band signal to a baseband signal in order to process the received user data, control information, wireless signal / channel, etc. using one or more processors (102, 202).One or more transceivers (106, 206) can convert user data, control information, wireless signals / channels, etc. processed using one or more processors (102, 202) from baseband signals to RF band signals. To this end, one or more transceivers (106, 206) may include (analog) oscillators and / or filters.

[0031] For example, one of the STAs (100, 200) may perform the intended operation of an AP, and the other of the STAs (100, 200) may perform the intended operation of a non-AP STA. For example, the transceiver (106, 206) of FIG. 1 may perform the operation of transmitting and receiving signals (e.g., packets or PPDU (Physical Layer Protocol Data Unit) according to IEEE 802.11a / b / g / n / ac / ax / be / bn, etc.). Additionally, the operation of generating transmission and reception signals or performing data processing or calculations in advance for transmission and reception signals by various STAs in the present disclosure may be performed by the processor (102, 202) of FIG. 1. For example, an example of an operation to generate a transmission and reception signal or to perform data processing or operations in advance for a transmission and reception signal may include: 1) an operation to determine / acquire / configure / operate / decode / encode bit information of fields (SIG (signal), STF (short training field), LTF (long training field), Data, etc.) included in the PPDU; 2) an operation to determine / configure / acquire time resources or frequency resources (e.g., subcarrier resources) used for fields (SIG, STF, LTF, Data, etc.) included in the PPDU; 3) an operation to determine / configure / acquire specific sequences (e.g., pilot sequence, STF / LTF sequence, extra sequence applied to SIG) used for fields (SIG, STF, LTF, Data, etc.) included in the PPDU; 4) power control operations and / or power saving operations applied to the STA; and 5) operations related to determining / acquiring / configuring / operating / decoding / encoding of an ACK signal. In addition, various information (e.g., information related to fields, subfields, control fields, parameters, power, etc.) used by various STAs for determining / acquiring / configuring / calculating / decoding / encoding transmission and reception signals in the following example can be stored in the memory (104, 204) of FIG. 1.

[0032] In the following, the downlink (DL) refers to a link for communication from an AP STA to a non-AP STA, and downlink PPDUs, packets, signals, etc., can be transmitted and received through the downlink. In downlink communication, the transmitter may be part of the AP STA, and the receiver may be part of the non-AP STA. The uplink (UL) refers to a link for communication from a non-AP STA to an AP STA, and uplink PPDUs, packets, signals, etc., can be transmitted and received through the uplink. In uplink communication, the transmitter may be part of the non-AP STA, and the receiver may be part of the AP STA.

[0033] FIG. 2 is a drawing showing an exemplary structure of a wireless LAN system to which the present disclosure can be applied.

[0034] The structure of a wireless LAN system can be composed of multiple components. Through the interaction of multiple components, a wireless LAN that supports STA mobility transparent to the upper layer can be provided. A Basic Service Set (BSS) corresponds to the basic building block of a wireless LAN. Figure 2 exemplarily illustrates the existence of two BSSs (BSS1 and BSS2) and the inclusion of two STAs as members of each BSS (STA1 and STA2 are included in BSS1, and STA3 and STA4 are included in BSS2). In Figure 2, the ellipse representing the BSS can also be understood as representing the coverage area where the STAs included in the corresponding BSS maintain communication. This area can be referred to as a Basic Service Area (BSA). If a STA moves outside the BSA, it becomes unable to communicate directly with other STAs within that BSA.

[0035] Excluding the DS illustrated in Fig. 2, the most basic type of BSS in a wireless LAN is the Independent BSS (IBSS). For example, an IBSS can have a minimal form consisting of only two STAs. For instance, assuming other components are omitted, a BSS1 composed of only STA1 and STA2, or a BSS2 composed of only STA3 and STA4, can each be considered a representative example of an IBSS. Such a configuration is possible when the STAs can communicate directly without an AP. Furthermore, this type of wireless LAN is not configured through pre-planning but can be configured when a LAN is needed, and this can be referred to as an ad-hoc network. Since an IBSS does not include an AP, there is no centralized management entity. In other words, in an IBSS, STAs are managed in a distributed manner. In IBSS, all STAs can be mobile STAs, and since connections to distributed systems (DS) are not allowed, they form a self-contained network.

[0036] The membership of an STA in a BSS can be dynamically changed by the STA being turned on or off, or by the STA entering or leaving the BSS area. 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 configured dynamically and may include the use of a Distribution System Service (DSS).

[0037] In a wireless LAN, the direct STA-to-STA distance may be limited by PHY performance. In some cases, this distance limit may be sufficient, but in others, communication between STAs over longer distances may be required. To support extended coverage, a distributed system (DS) may be configured.

[0038] DS refers to a structure in which BSSs are interconnected. Specifically, as shown in FIG. 2, a BSS may exist as a component in an extended form of a network composed of multiple BSSs. DS is a logical concept and can be specified by the characteristics of the Distributed System Medium (DSM). In this regard, the Wireless Medium (WM) and the DSM can be logically distinguished. Each logical medium is used for a different purpose and is utilized by different components. These media are not limited to being identical or different. The flexibility of the wireless LAN structure (DS structure or other network structure) can be explained by the fact that multiple media are logically distinct in this way. That is, the wireless LAN structure can be implemented in various ways, and the corresponding wireless LAN structure can be specified independently by the physical characteristics of each implementation.

[0039] DS can support mobile devices by providing seamless integration of multiple BSSs and providing logical services necessary for handling addresses to destinations. Additionally, DS may include a component called a portal that acts as a bridge for connecting the wireless LAN with another network (e.g., IEEE 802.X).

[0040] An AP refers to an entity that enables access to a DS via a WM for combined non-AP STAs and also possesses the functionality of an STA. Data movement between a BSS and a DS can be performed through the AP. For example, STA2 and STA3 shown in FIG. 2 possess the functionality of an STA and provide the ability for combined non-AP STAs (STA1 and STA4) to access a DS. Furthermore, since all APs fundamentally correspond to STAs, all APs are addressable entities. The address used by the AP for communication on the WM and the address used by the AP for communication on the DSM do not necessarily have to be the same. A BSS composed of an AP and one or more STAs can be referred to as an infrastructure BSS.

[0041] Data transmitted from one of the STA(s) coupled to the AP to the STA address of the AP can always be received at an uncontrolled port and processed by an IEEE 802.1X port access entity. Additionally, if the controlled port is authenticated, the transmitted data (or frame) can be forwarded to the DS.

[0042] In addition to the structure of the aforementioned DS, an Extended Service Set (ESS) may be configured to provide wider coverage.

[0043] An ESS refers to a network of arbitrary size and complexity composed of DSs and BSSs. An ESS can correspond to a set of BSSs connected to a single DS. However, an ESS does not contain a DS. An ESS network is characterized by appearing as an IBSS at the Logical Link Control (LLC) layer. STAs included in an ESS can communicate with each other, and mobile STAs can move from one BSS to another (within the same ESS) transparently to the LLC. APs included in a single ESS can have the same Service Set Identification (SSID). The SSID is distinct from the BSSID, which is the identifier for the BSS.

[0044] In wireless LAN systems, no assumptions are made regarding the relative physical locations of BSSs, and all of the following forms are possible. BSSs may partially overlap, which is 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 may be located in the same physical location, which can be used to provide redundancy. Also, one (or more) IBSS or ESS networks may physically exist in the same space as one (or more) ESS networks. This may apply to ESS network forms such as when an ad-hoc network operates at a location where an ESS network exists, when wireless networks that physically overlap are configured by different organizations, or when two or more different access and security policies are required at the same location.

[0045] FIG. 3 is a diagram illustrating a link setup process to which the present disclosure can be applied.

[0046] In order for an STA to set up a link and transmit and receive data on a network, it must first discover the network, perform authentication, establish an association, and go through authentication procedures for security. The link setup process can also be referred to as the session initiation process or the session setup process. Additionally, the processes of discovery, authentication, association, and security setup in the link setup process can be collectively referred to as the association process.

[0047] In step S310, the STA may perform a network discovery operation. The network discovery operation may include the STA's scanning operation. That is, in order for the STA to access a network, it must find a network it can join. Before joining a wireless network, the STA must identify a compatible network, and the process of identifying networks existing in a specific area is called scanning.

[0048] Scanning methods include active scanning and passive scanning. Figure 3 illustrates a network discovery operation that includes an active scanning process as an example. In active scanning, the STA performing the scanning moves between channels to search for nearby APs, transmits a probe request frame, and waits for a response. The responder transmits a probe response frame as a response to the probe request frame to the STA that transmitted the probe request frame. Here, the responder may be the STA that last transmitted a beacon frame from the BSS of the channel being scanned. In a BSS, the AP becomes the responder because it transmits the beacon frame; however, in an IBSS, the responder is not constant because STAs within the IBSS take turns transmitting the beacon frame. For example, an STA that transmits a probe request frame on channel 1 and receives a probe response frame on channel 1 can store BSS-related information included in the received probe response frame and move to the next channel (e.g., channel 2) to perform scanning in the same way (i.e., transmit and receive probe request / response on channel 2).

[0049] Although not illustrated in FIG. 3, the scanning operation may be performed using a passive scanning method. In passive scanning, the STA performing the scanning waits for a beacon frame while switching between channels. A beacon frame is one of the management frames defined in IEEE 802.11, which is periodically transmitted to announce the presence of a wireless network and to allow the scanning STA to find the wireless network and join it. In a BSS, the AP performs the role of periodically transmitting beacon frames, and in an IBSS, the STAs within the IBSS take turns transmitting beacon frames. When the scanning STA receives a beacon frame, it stores the information about the BSS included in the beacon frame and records the beacon frame information in each channel while moving to another channel. The STA that receives the beacon frame stores the BSS-related information included in the received beacon frame and moves to the next channel, and can perform scanning in the next channel in the same way. When comparing active scanning and passive scanning, active scanning has the advantage of lower delay and power consumption than passive scanning.

[0050] After the STA discovers the network, an authentication process may be performed in step S320. This authentication process may be referred to as the first authentication process to clearly distinguish it from the security setup operation in step S340 described later.

[0051] The authentication process involves the STA sending an authentication request frame to the AP, and the AP sending an authentication response frame to the STA in response. The authentication frame used in the authentication request / response corresponds to a management frame.

[0052] The authentication frame may include information regarding the authentication algorithm number, authentication transaction sequence number, status code, challenge text, Robust Security Network (RSN), Finite Cyclic Group, etc. These are some examples of information that may be included in the authentication request / response frame, and they may be replaced with other information or additional information may be included.

[0053] The STA can send an authentication request frame to the AP. Based on the information contained in the received authentication request frame, the AP can determine whether to allow authentication for the STA. The AP can provide the result of the authentication process to the STA through an authentication response frame.

[0054] After the STA is successfully authenticated, the association process can be performed in step S330. The association process includes the STA transmitting an association request frame to the AP, and in response, the AP transmitting an association response frame to the STA.

[0055] For example, the association request frame may include information regarding various capabilities, beacon listen interval, service set identifier (SSID), supported rates, supported channels, RSN, mobility domain, supported operating classes, Traffic Indication Map Broadcast request, interworking service capabilities, etc. For example, the association response frame may include information regarding various capabilities, status code, Association ID (AID), supported rates, Enhanced Distributed Channel Access (EDCA) parameter set, Received Channel Power Indicator (RCPI), Received Signal to Noise Indicator (RSNI), mobility domain, timeout interval (e.g., association comeback time), overlapping BSS scan parameters, TIM broadcast response, Quality of Service (QoS) map, etc. These are some examples of information that may be included in a combined request / response frame, and may be replaced with other information or additional information may be included.

[0056] After the STA is successfully joined to the network, a security setup process can be performed in step S340. The security setup process in step S340 may be described as an authentication process through RSNA (Robust Security Network Association) requests / responses, and the authentication process in step S320 may be referred to as the first authentication process, and the security setup process in step S340 may simply be referred to as the authentication process.

[0057] The security setup process of step S340 may include, for example, a private key setup process through a 4-way handshake via an EAPOL (Extensible Authentication Protocol over LAN) frame. Additionally, the security setup process may be performed according to a security method not defined in the IEEE 802.11 standard.

[0058] FIG. 4 is a drawing illustrating a backoff process to which the present disclosure may be applied.

[0059] In wireless LAN systems, the basic access mechanism for MAC (Medium Access Control) is the CSMA / CA (Carrier Sense Multiple Access with Collision Avoidance) mechanism. The CSMA / CA mechanism is also known as the Distributed Coordination Function (DCF) of IEEE 802.11 MAC, and it basically employs a "listen before talk" access mechanism. According to this type of access mechanism, the AP and / or STA may perform Clear Channel Assessment (CCA) to sense the wireless channel or medium for a predetermined time interval (e.g., DIFS (DCF Inter-Frame Space)) before starting transmission. If the sensing result determines that the medium is in an idle status, it starts transmitting a frame through that medium. On the other hand, if the medium is detected to be occupied or busy, the AP and / or STA may not start its own transmission but wait by setting a delay period for medium access (e.g., a random backoff period) before attempting to transmit a frame. By applying a random backoff period, multiple STAs are expected to attempt to transmit frames after waiting for different periods of time, thereby minimizing collisions.

[0060] In addition, the IEEE 802.11 MAC protocol provides a Hybrid Coordination Function (HCF). The HCF is based on the aforementioned Point Coordination Function (PCF). The PCF is a polling-based synchronous access method that periodically polls to ensure all receiving APs and / or STAs can receive data frames. Furthermore, the HCF includes Enhanced Distributed Channel Access (EDCA) and Controlled Channel Access (HCCA). EDCA is a contention-based access method for a provider to offer data frames to multiple users, while HCCA uses a non-contention-based channel access method utilizing a polling mechanism. Additionally, the HCF includes a media access mechanism to improve the Quality of Service (QoS) of the wireless LAN and can transmit QoS data during both the Contention Period (CP) and the Contention-Free Period (CFP).

[0061] Referring to FIG. 4, the operation based on the random backoff period is described. When a medium in an occupied / busy state changes to an idle state, multiple STAs may attempt to transmit data (or frames). As a measure to minimize collisions, each STA may select a random backoff count and attempt transmission after waiting for the corresponding slot time. The random backoff count has a pseudo-random integer value and can be determined as one of the values ​​in the range from 0 to CW. Here, CW is the Contention Window parameter value. The CW parameter is given an initial value of CWmin, but in the case of transmission failure (e.g., failure to receive an ACK for a transmitted frame), it may take a value twice that amount. When the CW parameter value becomes CWmax, data transmission may be attempted while maintaining the CWmax value until data transmission is successful; if data transmission is successful, it is reset to the CWmin value. The values ​​of CW, CWmin, and CWmax are 2 n It is desirable to set it to -1 (n=0, 1, 2, ...).

[0062] When the random backoff process begins, the STA continues to monitor the media while counting down the backoff slots according to the determined backoff count value. When the media is monitored as occupied, it stops the countdown and waits, and when the media becomes idle, it resumes the remaining countdown.

[0063] In the example of Fig. 4, when a packet to be transmitted arrives at the MAC of STA3, STA3 confirms that the medium is idle for DIFS and can immediately transmit the frame. The remaining STAs monitor whether the medium is occupied or busy and wait. Meanwhile, data to be transmitted may also arise from each of STA1, STA2, and STA5, and each STA can perform a countdown of the backoff slot according to a random backoff count value selected by each after waiting for DIFS when the medium is monitored to be idle. Assume the case where STA2 selects the smallest backoff count value and STA1 selects the largest backoff count value. That is, this exemplifies a case where, at the point when STA2 finishes the backoff count and starts transmitting the frame, the remaining backoff time of STA5 is shorter than the remaining backoff time of STA1. STA1 and STA5 pause the countdown briefly and wait while STA2 occupies the medium. When STA2's possession ends and the medium becomes idle again, STA1 and STA5 wait for DIFS and then resume the paused backoff count. That is, they can start transmitting a frame after counting down the remaining backoff slots corresponding to the remaining backoff time. Since STA5's remaining backoff time was shorter than STA1's, STA5 starts transmitting the frame. While STA2 is occupying the medium, data to be transmitted may also be generated by STA4. From STA4's perspective, when the medium becomes idle, it waits for DIFS, performs a countdown based on a random backoff count value selected by itself, and can start transmitting a frame. The example in Figure 4 illustrates a case where STA5's remaining backoff time happens to match STA4's random backoff count value; in this case, a collision may occur between STA4 and STA5. If a collision occurs, neither STA4 nor STA5 receives an ACK, resulting in a failure to transmit data.In this case, STA4 and STA5 can double the CW value, select a random backoff count value, and perform a countdown. STA1 waits while the medium is occupied due to transmission by STA4 and STA5, and when the medium becomes idle, it waits for DIFS, and then can start transmitting frames after the remaining backoff time has passed.

[0064] As shown in the example in Fig. 4, a data frame is a frame used for transmitting data that is forwarded to an upper layer, and can be transmitted after a backoff performed after the elapsed time of DIFS from when the medium becomes idle. Additionally, a management frame is a frame used for exchanging management information that is not forwarded to an upper layer, and is transmitted after a backoff performed after the elapsed time of an IFS such as DIFS or PIFS (Point coordination function IFS). Subtypes of management frames include Beacon, Association request / response, re-association request / response, probe request / response, and authentication request / response. A control frame is a frame used to control access to the medium. Subtype frames of control frames include RTS (Request-To-Send), CTS (Clear-To-Send), ACK (Acknowledgment), PS-Poll (Power Save-Poll), Block ACK (BlockAck), Block ACK Request (BlockACKReq), NDP Announcement (null data packet announcement), and Trigger. If a control frame is not an acknowledgment frame of a previous frame, it is transmitted after a backoff performed after the elapsed DIFS; if it is an acknowledgment frame of a previous frame, it is transmitted after the elapsed SIFS (short IFS) without a backoff. The type and subtype of a frame can be identified by the type field and subtype field within the Frame Control (FC) field.

[0065] A QoS (Quality of Service) STA can transmit a frame after backoff, which is performed after the passage of the arbitration IFS (AIFS) for the access category (AC) to which the frame belongs, i.e., AIFS[i] (where i is a value determined by the AC). Here, the frame for which AIFS[i] can be used can be a data frame or a management frame, and can also be a control frame rather than a response frame.

[0066] FIG. 5 is a diagram illustrating a CSMA / CA-based frame transmission operation to which the present disclosure may be applied.

[0067] As previously mentioned, the CSMA / CA mechanism includes virtual carrier sensing in addition to physical carrier sensing, where the STA directly senses the medium. Virtual carrier sensing is intended to mitigate problems that may occur in medium access, such as the hidden node problem. For virtual carrier sensing, the STA's MAC can utilize the Network Allocation Vector (NAV). The NAV is a value that indicates to other STAs the time remaining until the medium becomes available, provided that the STA currently using or authorized to use the medium is using it. Therefore, the value set as the NAV corresponds to the period during which the medium is scheduled to be used by the STA transmitting the frame, and the STA receiving the NAV value is prohibited from accessing the medium during that period. For example, the NAV can be set based on the value of the "duration" field in the frame's MAC header.

[0068] In the example of FIG. 5, it is assumed that STA1 intends to transmit data to STA2, and STA3 is located in a position where it can overhear part or all of the frames transmitted and received between STA1 and STA2.

[0069] In order to reduce the possibility of collisions between multiple STAs in a CSMA / CA-based frame transmission operation, a mechanism utilizing RTS / CTS frames may be applied. In the example of FIG. 5, while STA1 is transmitting, the medium may be determined to be idle based on the carrier sensing result of STA3. That is, STA1 may be a hidden node to STA3. Alternatively, in the example of FIG. 5, while STA2 is transmitting, the medium may be determined to be idle based on the carrier sensing result of STA3. That is, STA2 may be a hidden node to STA3. By exchanging RTS / CTS frames before performing data transmission and reception between STA1 and STA2, it is possible to prevent a STA outside the transmission range of either STA1 or STA2, or a STA outside the carrier sensing range for transmission from STA1 or STA3, from attempting to occupy the channel during data transmission and reception between STA1 and STA2.

[0070] Specifically, STA1 can determine whether the channel is in use through carrier sensing. In terms of physical carrier sensing, STA1 can determine the channel occupancy idle state based on the energy magnitude or signal correlation detected in the channel. Additionally, in terms of virtual carrier sensing, STA1 can determine the channel occupancy state using a NAV (network allocation vector) timer.

[0071] If the channel is idle during DIFS, STA1 can send an RTS frame to STA2 after performing backoff. If STA2 receives the RTS frame, it can send a CTS frame to STA1 as a response to the RTS frame after SIFS.

[0072] If STA3 cannot overhear a CTS frame from STA2 but can overhear an RTS frame from STA1, STA3 can set a NAV timer for the duration of subsequently transmitted frames (e.g., SIFS + CTS frame + SIFS + data frame + SIFS + ACK frame) using the duration information included in the RTS frame. Alternatively, if STA3 cannot overhear an RTS frame from STA1 but can overhear a CTS frame from STA2, STA3 can set a NAV timer for the duration of subsequently transmitted frames (e.g., SIFS + data frame + SIFS + ACK frame) using the duration information included in the CTS frame. That is, if STA3 can overhear one or more of the RTS or CTS frames from one or more of STA1 or STA2, it can set a NAV accordingly. If STA3 receives a new frame before the NAV timer expires, it can update the NAV timer using the duration information contained in the new frame. STA3 does not attempt channel access until the NAV timer expires.

[0073] If STA1 receives a CTS frame from STA2, it may transmit a data frame to STA2 after SIFS from the time the reception of the CTS frame is completed. If STA2 successfully receives the data frame, it may transmit an ACK frame to STA1 as an acknowledgment to the data frame after SIFS. STA3 may determine whether the channel is in use through carrier sensing when the NAV timer expires. If STA3 determines that the channel is not in use by another terminal during DIFS from the time the NAV timer expires, it may attempt channel access after a contention window (CW) based on random backoff has passed.

[0074] FIG. 6 is a drawing for illustrating an example of a frame structure used in a wireless LAN system to which the present disclosure may be applied.

[0075] Based on instructions or primitives (meaning a set of instructions or parameters) from the MAC layer, the PHY layer can prepare the MPDU (MAC PDU) to be transmitted. For example, upon receiving an instruction from the MAC layer requesting the start of transmission, the PHY layer switches to transmit mode and can construct the information provided by the MAC layer (e.g., data) into a frame for transmission. Additionally, if the PHY layer detects a valid preamble of a received frame, it monitors the preamble header and sends an instruction to the MAC layer indicating the start of reception.

[0076] As such, information transmission and reception in wireless LAN systems are carried out in the form of frames, and for this purpose, the Physical Layer Protocol Data Unit (PPDU) format is defined.

[0077] A basic PPDU may include a Short Training Field (STF), a Long Training Field (LTF), a Signal (SIGNAL) field, and a Data field. The most basic (e.g., the non-HT (High Throughput)) PPDU format illustrated in FIG. 7 may consist only of Legacy-STF (Legacy-STF), Legacy-LTF (Legacy-LTF), Legacy-SIG (Legacy-SIG) fields and a Data field. In addition, depending on the type of PPDU format (e.g., HT-mixed format PPDU, HT-greenfield format PPDU, VHT (Very High Throughput) PPDU, etc.), additional (or other types of) RL-SIG, U-SIG, non-legacy SIG fields, non-legacy STF, non-legacy LTF, (i.e., xx-SIG, xx-STF, xx-LTF (e.g., xx is HT, VHT, HE, EHT, etc.)) may be included between the L-SIG field and the data field. More specific details will be described later with reference to FIG. 7.

[0078] STF is a signal for signal detection, AGC (Automatic Gain Control), diversity selection, and precise time synchronization, while LTF is a signal for channel estimation and frequency error estimation. STF and LTF can be considered signals for synchronization and channel estimation in the OFDM physical layer.

[0079] The SIG field may contain various information related to the transmission and reception of the PPDU. For example, the L-SIG field consists of 24 bits and may 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 may contain information regarding the modulation and coding rates of the data. For example, the 12-bit Length field may contain information regarding the length or time duration of the PPDU. For example, the value of the 12-bit Length field may be determined based on the type of the PPDU. For example, for non-HT, HT, VHT, or EHT PPDUs, the value of the Length field may be determined as a multiple of 3. For example, for HE PPDUs, the value of the Length field may be determined as a multiple of 3 + 1 or a multiple of 3 + 2.

[0080] The data field may include a SERVICE field, a PSDU (Physical layer Service Data Unit), and PPDU TAIL bits, and may also include padding bits if necessary. Some bits of the SERVICE field may be used for synchronization of the descrambler at the receiver. The PSDU corresponds to a MAC PDU defined at the MAC layer and may contain data generated or used by the upper layer. The PPDU TAIL bits may be used to return the encoder to a 0 state. Padding bits may be used to adjust the length of the data field to a predetermined unit.

[0081] A MAC PDU is 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). A MAC frame is composed of a MAC PDU and can be transmitted or received through the PSDU of the data portion in the PPDU format.

[0082] The MAC header includes a Frame Control field, a Duration / ID field, an Address field, etc. The Frame Control field may contain control information necessary for transmitting or receiving frames. The Duration / ID field may be set as the time for transmitting the corresponding frame. Address subfields may indicate the frame's receiver address, transmitter address, destination address, and source address, and some address subfields may be omitted. Specific details regarding each subfield of the MAC header, including Sequence Control, QoS Control, and HT Control subfields, can be found in the IEEE 802.11 standard document.

[0083] The Null-Data PPDU (NDP) format refers to a PPDU format that does not include a data field. In other words, NDP is a frame format that includes the PPDU preamble (i.e., L-STF, L-LTF, L-SIG fields, and additionally, non-legacy SIG, non-legacy STF, and non-legacy LTF if present) from a standard PPDU format, but excludes the remaining parts (i.e., the data field).

[0084] FIG. 7 is a drawing illustrating examples of PPDUs defined in the IEEE 802.11 standard to which the present disclosure may be applied.

[0085] Various forms of PPDU 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 Data fields. The basic PPDU format may also be referred to as the non-HT PPDU format (Fig. 7(a)).

[0086] The HT PPDU format (IEEE 802.11n) additionally includes HT-SIG, HT-STF, and HT-LFT(s) fields in addition to the basic PPDU format. The HT PPDU format illustrated in FIG. 7(b) may be referred to as the HT-mixed format. Additionally, an HT-greenfield format PPDU may be defined, which corresponds to a format consisting of HT-GF-STF, HT-LTF1, HT-SIG, one or more HT-LTFs, and a Data field, without including L-STF, L-LTF, and L-SIG (not shown).

[0087] An example of the VHT PPDU format (IEEE 802.11ac) includes the VHT SIG-A, VHT-STF, VHT-LTF, and VHT-SIG-B fields in addition to the basic PPDU format (Fig. 7(c)).

[0088] An example of the HE PPDU format (IEEE 802.11ax) includes the RL-SIG (Repeated L-SIG), HE-SIG-A, HE-SIG-B, HE-STF, HE-LTF(s), and PE (Packet Extension) fields in addition to the basic PPDU format (Fig. 7(d)). Depending on specific examples of the HE PPDU format, some fields may be excluded or their lengths may vary. For example, the HE-SIG-B field is included in the HE PPDU format for multiple users (MU), but is not included in the HE PPDU format for single users (SU). Additionally, the HE trigger-based (TB) PPDU format does not include HE-SIG-B, and the length of the HE-STF field may vary to 8 microseconds (us). The HE ER (Extended Range) SU PPDU format does not include the HE-SIG-B field, and the length of the HE-SIG-A field may vary to 16us. For example, RL-SIG can be configured identically to L-SIG. Based on the presence of RL-SIG, the receiving STA can determine that the received PPDU is a HE PPDU or the EHT PPDU described later.

[0089] The EHT PPDU format may include the EHT MU (multi-user) of FIG. 7(e) and the EHT TB (trigger-based) PPDU of FIG. 7(f). The EHT PPDU format is similar to the HE PPDU format in that it includes RL-SIG following L-SIG, but it may include U (universal)-SIG, EHT-SIG, EHT-STF, and EHT-LTF following RL-SIG.

[0090] The EHT MU PPDU of FIG. 7(e) corresponds to a PPDU that carries one or more data (or PSDU) for one or more users. That is, the EHT MU PPDU can be used for both SU transmission and MU transmission. For example, the EHT MU PPDU can correspond to a PPDU for one receiving STA or multiple receiving STAs.

[0091] The EHT-SIG is omitted in the EHT TB PPDU of FIG. 7(f) compared to the EHT MU PPDU. A STA that receives a trigger for UL MU transmission (e.g., a trigger frame or TRS (triggered response scheduling)) can perform UL transmission based on the EHT TB PPDU format.

[0092] The L-STF, L-LTF, L-SIG, RL-SIG, U-SIG (Universal SIGNAL), and EHT-SIG fields can be encoded and modulated so that demodulation and decoding can be attempted even on legacy STAs, and mapped based on a defined 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 so that they can be demodulated and decoded by a STA that has successfully decoded a non-legacy SIG (e.g., U-SIG and / or EHT-SIG) to obtain the information contained in the corresponding fields, and mapped based on a defined subcarrier frequency interval (e.g., 78.125 kHz). These can be referred to as EHT modulated fields.

[0093] 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. Also, in the VHT PPDU format, the L-STF, L-LTF, L-SIG, and VHT-SIG-A fields can be referred to as pre-VHT modulation fields, and the VHT STF, VHT-LTF, VHT-SIG-B, and Data fields can be referred to as VHT modulation fields.

[0094] The U-SIG included in the EHT PPDU format of FIG. 7 can be constructed based on, for example, two symbols (e.g., two consecutive OFDM symbols). Each symbol for the U-SIG (e.g., OFDM symbol) can have a duration of 4 µs, and the U-SIG can have a total duration of 8 µs. Each symbol of the U-SIG can be used to transmit 26 bits of information. For example, each symbol of the U-SIG can be transmitted and received based on 52 data tones and 4 pilot tones.

[0095] U-SIGs can be configured in 20 MHz units. For example, if an 80 MHz PPDU is configured, the same U-SIG can be duplicated in 20 MHz units. That is, four identical U-SIGs can be included within an 80 MHz PPDU. If the bandwidth exceeds 80 MHz, for example, for a 160 MHz PPDU, the U-SIG of the first 80 MHz unit and the U-SIG of the second 80 MHz unit may be different.

[0096] For example, A number of uncoded bits may be transmitted through U-SIG, and the first symbol of U-SIG (e.g., U-SIG-1 symbol) transmits the first X bits of the total A bit information, and the second symbol of U-SIG (e.g., U-SIG-2 symbol) transmits 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 field of 4 bits) and a tail field (e.g., a field of 6 bits). The tail field may be used to terminate the trellis of the convolution decoder and may be set to, for example, 0.

[0097] A bit information transmitted by U-SIG can be divided into version-independent bits and version-dependent bits. For example, U-SIG may be included in a new PPDU format not shown in FIG. 7 (e.g., UHR PPDU format), and 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-dependent bits may be different.

[0098] For example, the size of the version-independent bits of U-SIG may be fixed or variable. The version-independent bits may be assigned only to U-SIG-1 symbols or to both U-SIG-1 and U-SIG-2 symbols. The version-independent bits and version-dependent bits may be referred to by various names, such as the first control bit and the second control bit.

[0099] For example, the version-independent bits of U-SIG may include a 3-bit physical layer version identifier (PHY version identifier), and this information may indicate the PHY version of the transmitted / received PPDU (e.g., EHT, UHR, etc.). 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 relates to UL communication, and the second value of the UL / DL flag field relates to DL communication. The version-independent bits of U-SIG may include information regarding the length of the TXOP (transmission opportunity) and information regarding the BSS color ID.

[0100] For example, the version-dependent bits of U-SIG may contain information that directly or indirectly indicates the type of PPDU (e.g., SU PPDU, MU PPDU, TB PPDU, etc.).

[0101] Information necessary for PPDU transmission and reception may be included in the U-SIG. For example, the U-SIG may further include information regarding bandwidth, information regarding MCS techniques applied to non-legacy SIGs (e.g., EHT-SIG or UHR-SIG, etc.), information indicating whether DCM (dual carrier modulation) techniques (e.g., techniques to achieve an effect similar to frequency diversity by reusing the same signal on two subcarriers) are applied to non-legacy SIGs, information regarding the number of symbols used for non-legacy SIGs, and information regarding whether non-legacy SIGs are generated across the entire band.

[0102] Some of the information required for PPDU transmission and reception may be included in U-SIG and / or non-legacy SIGs (e.g., EHT-SIG or UHR-SIG, etc.). For example, information regarding the type of non-legacy LTF / STF (e.g., EHT-LTF / EHT-STF or UHR-LTF / UHR-STF, etc.), information regarding the length of non-legacy LTF and cyclic prefix (CP) length, information regarding guard interval (GI) applied to non-legacy LTF, information regarding preamble puncturing applicable to PPDU, information regarding resource unit (RU) allocation, etc., may be included only in U-SIG, may be included only in non-legacy SIG, or may be indicated by a combination of information included in U-SIG and information included in non-legacy SIG.

[0103] Preamble puncturing may refer to the transmission of a PPDU in which a signal is not present in one or more frequency units within the PPDU bandwidth. For example, the size of the frequency unit (or the resolution of preamble puncturing) may be defined as 20 MHz, 40 MHz, etc. For example, preamble puncturing may be applied to a PPDU bandwidth of a predetermined size or larger.

[0104] In the example of FIG. 7, non-legacy SIGs such as HE-SIG-B and EHT-SIG may include control information for the receiving STA. A non-legacy SIG may be transmitted through at least one symbol, and one symbol may have a length of 4 µs. Information regarding the number of symbols used for EHT-SIG may be included in the previous SIG (e.g., HE-SIG-A, U-SIG, etc.).

[0105] Non-legacy SIGs, such as HE-SIG-B and EHT-SIG, may include common fields and user-specific fields. Common fields and user-specific fields may be coded individually.

[0106] In some cases, the common field may be omitted. For example, in a compression mode where non-OFDMA (orthogonal frequency multiple access) is applied, the common field may be omitted, and multiple STAs may receive PPDUs (e.g., the data field of the PPDU) over the same frequency band. In a non-compression mode where OFDMA is applied, multiple users may receive PPDUs (e.g., the data field of the PPDU) over different frequency bands.

[0107] The number of user-specific fields can be determined based on the number of users. A single user block field can contain up to two user fields. Each user field may be related to MU-MIMO allocation or non-MU-MIMO allocation.

[0108] The common field may include CRC bits and Tail bits, the length of the CRC bits may be determined to be 4 bits, and the length of the Tail bits may be determined to be 6 bits and set to 000000. The common field may include RU allocation information. The RU allocation information may include information regarding the location of the RU to which a plurality of users (i.e., a plurality of receiving STAs) are allocated.

[0109] An RU may include multiple subcarriers (or tones). An RU may be used when transmitting signals to multiple STAs based on the OFDMA technique. Additionally, an RU may be defined when transmitting signals to a single STA. Resources may be allocated on an RU basis for non-legacy STF, non-legacy LTF, and Data fields.

[0110] Applicable RU sizes can be defined according to the PPDU bandwidth. RUs may be defined identically or differently for the applicable PPDU format (e.g., HE PPDU, EHT PPDU, UHR PPDU, etc.). For example, in the case of an 80 MHz PPDU, the RU placement for HE PPDU and EHT PPDU may differ. The applicable RU sizes, number of RUs, RU locations, DC (direct current) subcarrier locations and numbers, null subcarrier locations and numbers, and guard subcarrier locations and numbers for each PPDU bandwidth can be referred to as a tone-plan. For example, a tone-plan for a wide bandwidth may be defined as a multiple repetition of a tone-plan for a low bandwidth.

[0111] RUs of various sizes can be defined as 26-ton RUs, 52-ton RUs, 106-ton RUs, 242-ton RUs, 484-ton RUs, 996-ton RUs, 2x996-ton RUs, 4x996-ton RUs, etc. An MRU (multiple RU) is distinguished from multiple individual RUs and corresponds to a group of subcarriers composed of multiple RUs. For example, one MRU can be defined as 52+26-tons, 106+26-tons, 484+242-tons, 996+484-tons, 996+484+242-tons, 2x996+484-tons, 3x996-tons, or 3x996+484-tons. In addition, multiple RUs constituting a single MRU may be continuous or non-continuous in the frequency domain.

[0112] The specific size of the RU may be reduced or expanded. Accordingly, the specific size of each RU (i.e., the number of corresponding tones) in this disclosure is not limited and is exemplary. Additionally, within a given bandwidth (e.g., 20, 40, 80, 160, 320 MHz, ...) in this disclosure, the number of RUs may vary depending on the RU size.

[0113] The names of the respective fields in the PPDU formats of FIG. 7 are exemplary and the scope of the present disclosure is not limited by such names. Furthermore, the examples of the present disclosure may be applied not only to the PPDU formats exemplified in FIG. 7, but also to new PPDU formats based on the PPDU formats of FIG. 7 in which some fields are excluded and / or some fields are added.

[0114] Multiple Access Point (MAP) Operation

[0115] Examples of the present disclosure regarding multiple access point (MAP) operations are described below.

[0116] MAP operation can be defined as the operation between a master AP (or sharing AP) and a slave AP (or shared AP).

[0117] The master AP plays the role of initiating and controlling MAP operations for transmission and reception between multiple APs. The master AP groups slave APs and manages links with slave APs to enable information sharing among them. The master AP manages information about the BSS configured by the slave APs and information about the STAs that have formed an association with the BSS.

[0118] A slave AP forms a pair with a master AP and can share control information, management information, and data traffic. The slave AP performs the same basic functions as an AP, such as establishing a BSS in a wireless LAN.

[0119] In MAP operation, the STA can form a BSS by combining with a slave AP or a master AP.

[0120] In a MAP environment, the master AP and slave AP can perform direct transmission and reception with each other. The master AP and STA may not be able to perform direct transmission and reception with each other. A slave AP (for example, a slave AP coupled with a STA) can perform direct transmission and reception with the STA. One of the slave APs can become the master AP.

[0121] MAP operation is a technique in which one or more APs transmit and receive information to one or more STAs. For example, techniques such as C-TDMA (coordinated-time division multiple access), which divides allocation between APs along the time axis; C-OFDMA (coordinated-orthogonal frequency division multiple access), which divides along the frequency axis; and C-SR (coordinated-spatial reuse), which utilizes spatial reuse, can be applied for MAP operation. Alternatively, MAP operation may also apply coordinated beamforming (C-BF) or joint beamforming techniques, which perform simultaneous transmission and reception in cooperation.

[0122] FIG. 8 is a diagram illustrating various transmission and reception techniques in a MAP environment to which the present disclosure can be applied.

[0123] As with the existing method, the transmission performed by a BSS AP to a BSS STA can be referred to as STX (single transmission). In STX, there is a problem where the transmission and reception performance for users / STAs located at the cell edge is degraded due to interference with adjacent APs. For example, as shown in Fig. 8(a), if AP1 and AP2 perform transmissions to STA1 and STA2 respectively at the same time in the same frequency band, a collision may occur on the wireless medium.

[0124] In MAP techniques, performance can be improved by reducing inter-symbol interference (ISI) through cooperation among neighboring APs or by performing joint transmissions. For example, in the C-OFDMA method of Fig. 8(b), interference can be avoided by AP1 transmitting to STA1 in the first bandwidth and AP2 transmitting to STA2 in the second bandwidth at the same time. The example in Fig. 8(c) illustrates a cooperative beamforming or nulling technique in which AP1 nulls the interference affecting AP2 and / or STA2 while transmitting to STA1, and AP2 nulls the interference affecting AP1 and / or STA1 while transmitting to STA2. Fig. 8(d) illustrates an AP selection method in which the AP with the best channel conditions among adjacent APs performs the transmission. As shown in the example of Fig. 8(e), joint transmission (JTX) or joint reception (JRX) in which multiple APs cooperate to transmit or receive simultaneously may be applied, and furthermore, joint MU-MIMO may be supported.

[0125] RSN operation

[0126] As explained with reference to Fig. 3, after the discovery process between the STA and the AP, the authentication process can be performed in an open system manner, and the association process can be performed. This process can be described as Step 0, which involves searching for RSN (robust security network) support and establishing authentication and association.

[0127] If Step 0 is successfully completed, Step 1 can be performed to obtain a pairwise master key (PMK) and authenticate the user using IEEE 802.1X / EAP (extensible authentication protocol) or PSK (pre-shared key). The mutual authentication methods applied here may include 802.1X / EAP, PSK, or SAE (simultaneous authentication of equals). For example, in the case of the 802.1X / EAP authentication method, the PMK can be generated from the master session key (MSK) after authentication between the STA and RADIUS (remote authentication dial-in user service). In the case of user authentication using PSK, the AP and STA can directly set the PMK in the same way as with PSK. In the case of user authentication using SAE, the AP and STA can directly set the PMK using the mutual authentication and the computational value of the authentication process through the SAE authentication process.

[0128] Following Step 1, Step 2 may be performed to verify whether the counterparty possesses the same PMK using an EAPoL-Key frame, and to generate and share an encryption key. Step 2 may include a process of mutually verifying the PMK generation and generating and transmitting a group key (e.g., GTK (group temporal key)) through 4-way handshaking. Through 4-way handshaking, PTK (pairwise transient key), KCK (key confirmation key), KEK (key encryption key), and TK (temporal key) may be generated.

[0129] Specifically, in Step 1, a PMK can be generated from an MSK, and in Step 2, a PTK can be generated from the PMK. Here, the PTK is configured by separating it into a KCK, a KEK, and a TK. A GTK can be generated from an AP and delivered to an STA. If the AP wishes to generate a new GTK, it may perform a handshake with the STA and deliver the new GTK to the STA.

[0130] To verify whether the STA and AP possess the same PMK, in the case of 802.1X / EAP, the same MSK is established between the STA and the AS based on the user authentication result between the STA and the Authentication Server (AS), and the AS transmits the corresponding MSK to the AP. The STA and AP can verify with each other whether they possess the PMK, which is a symmetric key generated from the MSK, through a 4-way handshake. In the case of PSK, the authentication process can be replaced by mutually verifying through a 4-way handshake whether the AP and STA have secured the PMK generated from a pre-configured PSK. In the case of SAE, the AP and STA can mutually verify the pre-configured PMK through a 4-way handshake.

[0131] It can also be verified whether the STA and AP possess the same PMK by mutually verifying that they have generated the same PTK. For example, the acquisition of the PMK can be verified through Messages 2 and 3 of the 4-way handshake. Specifically, in Message 2, the STA can send the KCK of the PTK it generated to the AP by including it in the Key MIC field. In Message 3, the AP can send the KCK of the PTK it generated to the STA by including it in the Key MIC field. Through this, the STA (AP) can verify that the AP (STA) possesses the same PMK as itself by verifying that the AP (STA) has generated a PTK identical to its own. Meanwhile, in Message 1, the value of the Key MIC field may be set to 0, and in Message 4, the KCK value may be included in the Key MIC field.

[0132] In this way, a secret key can be generated to encrypt data to be transmitted and received between the STA and the AP in Step 2. In the RSN, a different secret key is generated for each STA combined with the AP, and another secret key is generated when the STA is re-combined with a different AP.

[0133] Based on the TK generated as a result of the 4-way handshake of Step 2, encryption of data can be performed using TKIP (temporal key integrity protocol), CCMP (cipher-block chaining message authentication code protocol), GCMP (Galois / Counter Mode protocol), etc., and this can be referred to as Step 3.

[0134] The aforementioned MSK, PSK, PMK, PTK, KCK, KEK, and TK correspond to pairwise keys, that is, keys paired between the AP and the STA. Unlike pairwise keys, the group key can be generated based on the GMK (group master key) to generate secret keys for frames group-addressed by the AP, such as beacon frames. The GMK is randomly set by the AP. The GTK (group temporal key) is generated from the GMK by the PRF (pseudorandom function) function and corresponds to a unidirectional group key from the AP to the STA.

[0135] FIG. 9 is a diagram illustrating a 4-way handshake procedure to which the present disclosure may be applied.

[0136] STA corresponds to the supervising party requesting authentication, and AP corresponds to the authenticating party performing authentication. A 4-way handshake can be performed between AP and STA to generate and verify PTK and GTK when STA possesses or knows PMK and AP possesses or knows PMK and GMK.

[0137] ANonce and SNonce correspond to arguments used in the PRF function used for PTK generation. ANonce may correspond to a random number generated by the access point (i.e., authenticator). SNonce may correspond to a random number generated by the STA (i.e., supplicant). The PRF function may correspond to a function that generates a PTK based on, for example, the PMK, ANonce, SNonce, the MAC address of the supplicant, and the MAC address of the authenticator.

[0138] Message 1 of step S810 is transmitted from the AP to the STA via unicast, and the EAPOL-key frame may include ANonce information. If the AP has generated a PMK, the PMKID may be included in the key data field of the EAPOL-key frame. The STA may generate a PTK based on the information received from the AP, and may generate KCK, KEK, and TK based on the PTK.

[0139] Message 2 of step S820 is transmitted from the STA to the AP via unicast, and the EAPOL-key frame may include SNonce information and a key MIC (message integrity code). For example, the key MIC of Message 2 may have a value based on the KCK generated by the STA. The AP can generate a PTK based on the information received from the STA, and can generate a KCK, KEK, and TK based on the PTK. The AP can verify whether the AP and the STA have generated the same PTK by checking whether the KCK value of the PTK generated based on the value included in Message 2 is the same as the KCK value associated with the key MIC value included in Message 2. Additionally, the AP can generate a GTK if necessary. The GTK can be generated from the GMK by the AP without the involvement of the STA.

[0140] Message 3 of step S830 is transmitted from the AP to the STA via unicast, and the EAPOL-key frame may include MIC (i.e., the KCK value of the PTK generated by the AP) and encrypted GTK information. The encrypted GTK of Message 3 may be encrypted based on the KEK generated by the AP and included in the key data field. The STA may store the PTK in the PTK-SA (PTK-Security Association) and the GTK in the GTK-SA.

[0141] Message 4 of step S840 is transmitted from the STA to the AP via unicast, and the EAPOL-key frame may include MIC information. Once verification is complete via the MIC, the AP can store the PTK in the PTK-SA and the GTK in the GTK-SA.

[0142] Once the 4-way handshake is successfully completed, the virtual control port that blocks all traffic is unblocked, and encrypted traffic can be transmitted and received. Subsequently, all unicast traffic can be encrypted by the PTK, and all multicast / broadcast traffic can be encrypted by the GTK.

[0143] RSNA Confidentiality and Integrity Protocol

[0144] For RSNA, authentication mechanisms for STAs, key management algorithms, cryptographic key establishment, cryptographic mechanisms, fast BSS transition (FT), cryptographic encapsulation for robust management frames, etc., may be defined. For example, cryptographic mechanisms may include CCMP (counter mode (CTR) with cipher-block chaining message authentication code (CBC-MAC) protocol), GCMP (Galois / Counter Mode protocol), etc.

[0145] RSNA security may include algorithms and procedures such as TKIP (temporal key integrity protocol), CCMP, GCMP, BIP (broadcast / multicast integrity protocol), RSNA establishment and termination procedures, and key management procedures (e.g., key distribution). For example, RSNA establishment and termination procedures may include IEEE 802.1X authentication, SAE (simultaneous authentication of equals) authentication, OWE (opportunistic wireless encryption) defined in IETF (internet engineering task force) RFC (request for comments) 8110, etc.

[0146] The following describes CCMP (counter mode (CTR) with cipher-block chaining message authentication code (CBC-MAC) protocol).

[0147] CCMP is a protocol that provides data confidentiality, authentication, integrity, and replay protection. CCMP is based on the CCM of the AES (Advanced Encryption Standard) encryption algorithm. CCM combines CTR for data confidentiality and CBC-MAC for authentication and integrity. CCM can protect the integrity of both the MPDU data fields and selected parts of the MPDU header (MAC header).

[0148] FIG. 9 is a drawing showing an example of an expanded CCMP MPDU to which the present disclosure can be applied.

[0149] For a secure PV0 (protocol version 0) MPDU, 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 is constructed from the PN (packet number), ExtIV (extended initialization vector), and Key ID subfield. The PN is a 48-bit PN represented as an array of 6 octets. PN5 is the most significant octet of the PN, and PN0 is the least significant octet. The third octet of the CCMP header is reserved. The ExtIV subfield of the key ID octet (bit 5 (B5)) is always set to 1 for CCMP, bits 6 (B6) and 7 (B7) are the key ID subfields, and the remaining bits of the key ID octet are reserved.

[0150] FIG. 10 shows a CCMP encapsulation block diagram to which the present disclosure can be applied.

[0151] Additional authentication data (AAD) can be constructed from the MAC header of a plaintext MPDU. A Nonce can be constructed based on the address 2 (A2) and priority of the plaintext MPDU, and the incremented PN. The AAD and Nonce can be used for CCM encryption along with the data and TK. A CCMP header can be constructed based on the incremented PN and Key ID. The data and MIC resulting from the CCM encryption, together with the MAC header and CCMP header, can form an encrypted MPDU such as the example in FIG. 9.

[0152] Figure 11 shows an example of the format of a conventional AAD.

[0153] The example in FIG. 11(a) may correspond to an example of an existing AAD construction for a PV0 MPDU. The FC (frame control), A1 (address 1), A2 (address 2), A3 (address 3), and SC (sequence control) fields may always be included in the existing AAD if they are included in the MAC header. The length of the AAD may vary depending on the presence or absence of the QC (QoS Control) field and the A4 (address 4) field. For the existing AAD, for example, if both QC and A4 are absent, the AAD length may be 22 octets; if QC is present and A4 is absent, the AAD length may be 24 octets; if QC is absent and A4 is present, the AAD length may be 28 octets; and if both QC and A4 are present, the AAD length may be 30 octets.

[0154] The AAD is constructed from the MPDU header. Referring to FIG. 11(b), the existing 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 that may be changed or inserted / deleted during operations such as retransmission are not included in the existing AAD.

[0155] Additionally, some subfields of the Frame Control (FC) field of the MAC header may be masked out. Masking out means changing the value of the corresponding subfield / field of the MAC header to 0 and including it in the AAD.

[0156] For example, the subfields that are masked out in the existing AAD FC field are as follows:

[0157] The 3 LSBs (i.e., bits 4, 5, and 6) of the subtype subfield of the data frame are masked out, and bit 7 is not modified;

[0158] The retry subfield is masked out;

[0159] The power management subfield (i.e., bit 12) is masked out;

[0160] The more data subfield (i.e., bit 13) is masked out;

[0161] The protected frame subfield (i.e., bit 14) is not modified (i.e., left as 1);

[0162] The +HTC subfield (i.e., bit 15) is masked out in all data frames containing the QoS control field, and is not modified otherwise;

[0163] Other subfields of the FC field are not modified.

[0164] For example, the sequence number subfield in the sequence control (SC) field of an existing AAD can be masked out.

[0165] Although not illustrated in the example of FIG. 11, if the existing AAD includes a QoS control (QC) field, the QC field may be included in the existing AAD if one or more of the MSDU priority subfield, QC TID (traffic identifier) ​​subfield, A-MSDU capable subfield, A-MSDU present subfield, and A-MSDU type subfield exist in the MAC header. Other subfields in the QC field of the existing AAD may be masked out. That is, the EOSP (end of service period) subfield, ACK policy indicator subfield, TXOP limit subfield, queue size subfield, TXOP duration requested subfield, and AP power save buffer state subfield may be masked out and not used in the existing AAD configuration.

[0166] FIG. 12 shows a CCMP decapsulation block diagram to which the present disclosure can be applied.

[0167] An AAD can be constructed from the MAC header of an encrypted MPDU. A Nonce can be constructed based on the A2 and priority of the encrypted MPDU and the PN. The AAD and Nonce can be used for CCM decryption along with the MIC, data, and key. The data resulting from CCM decryption can be subjected to a replay check along with the MAC header to obtain a plaintext MPDU. The replay check can be based on the PN and a replay counter.

[0168] The following describes BIP (broadcast / multicast integrity protocol).

[0169] BIP provides data integrity and replay protection for group-addressed robust management frames after establishing an integrity group temporal key security association (IGTKSA). For example, BIP provides data integrity and replay protection for beacon frames after establishing a beacon IGTKSA. BIP can calculate MAC management PDU MICs using IGTK or BIGTK. The management MIC element (MME) can be located after all other elements of the management frame body and before the FCS. That is, 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 IPN (IGTK packet number) / BIPN (BIGTK packet number) field, and a MIC field.

[0170] The existing AAD for the BIP can be configured based on FC, A1, A2, and A3, and the retry subfield (bit 11), power management subfield (bit 12), and More data subfield (bit 13) within FC are masked out, and other subfields may not be modified.

[0171] The following describes GCMP (Galois / Counter Mode protocol).

[0172] GCMP is a protocol that provides data confidentiality, authentication, integrity, and replay protection. EHT RSNA STA can support GCMP-256. GCMP is based on GCM of the AES (advanced encryption standard) encryption algorithm. GCM can protect the integrity of both the MPDU data field and selected parts of the MPDU header (MAC header).

[0173] FIG. 13 is a drawing showing an example of an expanded GCMP MPDU to which the present disclosure can be applied.

[0174] GCMP processing expands the original MPDU size by 24 octets (i.e., 8 octets for the GCMP header field and 16 octets for the MIC field). The GCMP header field is constructed from the PN (packet number) and key ID subfields. The PN is a 48-bit PN represented as an array of 6 octets. PN5 is the most significant octet of the 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 subfield, and the remaining bits of the key ID octet are reserved.

[0175] FIG. 14 shows a GCMP encapsulation block diagram to which the present disclosure can be applied.

[0176] Additional authentication data (AAD) can be constructed from the MAC header of a plaintext MPDU. A Nonce can be constructed based on the A2 (address 2) of the plaintext MPDU and the incremented PN. The AAD and Nonce can be used for GCM encryption along with the data and TK. A GCMP header can be constructed based on the incremented PN and the key ID. The data resulting from the CCM encryption, together with the MAC header and the CCMP header, can form an encrypted MPDU such as the example in FIG. 13.

[0177] The configuration of the existing AAD applied to GCMP is the same as described with reference to Fig. 11, so a redundant description is omitted.

[0178] FIG. 15 shows a GCMP decapsulation block diagram to which the present disclosure can be applied.

[0179] An AAD can be constructed from the MAC header of an encrypted MPDU. A Nonce can be constructed based on the A2 and PN of the encrypted MPDU. The AAD and Nonce can be used for GCM decryption along with the data and key. The data resulting from GCM decryption can be subjected to a replay check along with the MAC header to obtain a plaintext MPDU. The replay check can be based on the PN and a replay counter.

[0180] Block ACK Request (BAR) Frame

[0181] FIG. 16 is a diagram showing an exemplary format of a block-ACK request frame to which the present disclosure can be applied.

[0182] A block-ACK request frame may be intended to request the transmission of a block-ACK frame containing multiple acknowledgments in a single frame, thereby increasing channel efficiency. For example, a first STA (e.g., AP) may request a reception result for multiple MPDUs through a block-ACK request frame, and a second STA(s) that receives the block-ACK request frame may transmit a block-ACK frame containing acknowledgments for multiple MPDUs based on the request.

[0183] As illustrated in FIG. 16, a block-ACK request (BAR) frame may include a BAR control field and a BAR information field in the frame body.

[0184] The BAR control field may include a BAR type, TID information (TID_INFO), etc., indicating the type of block-ACK request frame (e.g., compressed, multi-TID, GCR (groupcast with retries), etc.).

[0185] The BAR information field may be based on the type of block-ACK request frame (e.g., block-ACK request frame variant type) indicated by the BAR type field / subfield within the BAR control information.

[0186] For example, if a compressed block-ACK request frame type (e.g., a compressed block-ACK frame type or an extended compressed block-ACK frame type) is specified, the BAR information field format corresponding to the compressed block-ACK request may include a Block Ack Starting Sequence Control subfield.

[0187] For example, the block-ACK start sequence control subfield may include a fragment number subfield and a starting sequence number subfield. Here, the fragment number subfield is set to 0, and the starting sequence number subfield may include the sequence number of the first MSDU or A-MSDU to which the corresponding block-ACK request frame is transmitted.

[0188] As another example, when a multi-STA block-ACK request frame type is indicated, the BAR information field format corresponding to the multi-STA block-ACK request may include, for each TID, a Per TID Info subfield and a block-ACK start sequence control subfield.

[0189] For example, each TID information subfield may include a 4-bit TID value subfield. Additionally, 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 is transmitted.

[0190] In this regard, the TID_INFO subfield of the BAR control field of a multi-TID block-ACK request frame can determine the number of TIDs present in the multi-TID block-ACK request frame given as TID_INFO + 1. For example, if the TID_INFO subfield is set to 2, it may mean that there are 3 TID values ​​in the BAR information field of the multi-TID block-ACK request frame.

[0191] As another example, when a GCR block-ACK request frame type is specified, 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 for which the reception status is requested. Additionally, 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 is transmitted.

[0192] As another example, when the GLK-GCR block-ACK request frame type is specified, 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 to which the corresponding block-ACK request frame is transmitted.

[0193] Configuration of additional authentication data (AAD) for Block Ack Request (BAR) frames

[0194] In existing wireless LAN systems, encryption and decryption based on TKIP (Temporal Key Integrity Protocol) / CCMP / GCMP using a pairwise transient key (PTK) can be performed and applied to individually addressed data frames (e.g., unicast-based data frames) and management frame(s). Additionally, encryption and decryption based on TKIP / CCMP / GCMP using a group temporal key (GTK) can be performed and applied to group addressed frames (e.g., broadcast-based data frames). That is, CCMP / GCMP is a security protocol that performs encryption and decryption; for single-user (SU) systems, a TK based on PTK is used, while for multi-user (MU) systems, a TK based on GTK can be used. CCMP / GCMP can guarantee the confidentiality and integrity of data frames and management frame(s).

[0195] Additionally, for group-addressed management frame(s), BIP-based integrity checks can be performed using the integrity group temporal key (IGTK). In particular, for beacon frames, BIP-based integrity checks can be performed using the beacon integrity group temporal key (BIGTK). In the case of BIP, a message integrity code (MIC) for the frame body of the corresponding data frame is generated using a TK based on IGTK / BIGTK, and an integrity check based on this can be performed. That is, unlike CCMP / GCMP, BIP can only guarantee the integrity of data frames and management frame(s).

[0196] The method of configuring MPDUs based on CCMP and GCMP and the method of configuring MMPDUs (management MPDUs) based on BIP have the following differences.

[0197] First, in the case of CCMP / GCMP, the sending STA encrypts the data portion using CCM / GCM and transmits 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 protocol to generate a MIC for checking the integrity of the data in the frame body.

[0198] Next, in the case of CCMP / GCMP, the MPDU can be configured and transmitted in the order of a MAC header, a CCMP / GCMP header, encrypted data, a MIC (encrypted MIC in the case of CCMP), and an FCS. In contrast, in the case of BIP, it can be configured and transmitted in the order of a MAC header, a management frame body containing an MME (management MIC element), and an FCS. Here, since the MME takes the place of the CCMP / GCMP header, it may include information on a Key ID field, IPN / BIPN, and MIC.

[0199] As mentioned above, protection is supported for management frames, including data frames and beacon frames, among group-addressed frames. However, protection is not supported for control frames; accordingly, control frames are transmitted and received without any encryption / decryption and / or integrity check protocols applied.

[0200] For example, ACK frames, block-ACK (BlockAck, Block Ack, BA) frames, and block-ACK request frames correspond to a type of control frame. When a transmitting STA transmits data, a receiving STA can transmit an ACK for that data to the transmitting STA. In this case, STA(s) that support A(aggregated)-MPDU can construct the ACK as an A-MPDU and transmit it in the form of a block-ACK.

[0201] A block-ACK request frame can be transmitted by the transmitting STA to receive a block-ACK from the receiving STA. That is, when the transmitting STA transmits a block-ACK request frame to the receiving STA, the receiving STA can transmit 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 the previous frame transmitted in the TXOP, or to initialize (e.g., clear) the receiving STA's receive re-order buffer.

[0202] In this regard, if the information of a block-ACK request frame is exposed to a third STA (e.g., an attack STA), it can acquire the ACK information, which serves to confirm whether data is being transmitted and received between the transmitting STA and the receiving STA, and thereby disrupt the transmission and reception between the transmitting STA and the receiving STA. As a result, an attack on a block-ACK request frame can lead to a degradation of data transmission and reception capabilities and a waste of power / medium.

[0203] In consideration of these points, the present disclosure proposes a security technology to ensure the confidentiality and integrity of block-ACK request frames transmitted and received between a transmitting STA and a receiving STA.

[0204] Additionally, in the description of the present disclosure, it is assumed that the STA(s) transmitting and receiving the block-ACK request frame according to the present disclosure are UHR STAs (and / or beyond UHR STAs). For example, when utilizing the block-ACK request frame according to the present disclosure, it can be assumed that all receiving STAs receiving the block-ACK request frame transmitted by the AP, which is the transmitting STA, are UHR STAs. That is, if a block-ACK request frame configured according to the method proposed in the present disclosure is received by a pre-UHR STA (e.g., EHT / HE STA, etc.), an error may occur during decoding of the block-ACK request frame.

[0205] Additionally, although the present disclosure describes a security technique for a block-ACK request frame among control frames as a representative example, the proposed method of the present disclosure can be extended and applied to other types of control frames other than block-ACK request frames.

[0206] In the present disclosure, performing confidentiality and integrity checks on block ACK request frames can be interpreted as extending and applying BIP / CCMP / GCMP to block ACK request frames. In this regard, additional provisions for control frames may be defined for the previously defined BIP / CCMP / GCMP, or a separate protocol based on BIP / CCMP / GCMP for checking the confidentiality and integrity of control frames may be newly defined.

[0207] Specific examples of the present disclosure that support / perform protection (e.g., confidentiality and integrity checks) for block-ACK request frames are described below. The names and values ​​of fields, subfields, elements, parameters, keys, etc. proposed in the present disclosure are exemplary and are not limited to such names and values. Additionally, unless otherwise distinguished, a STA may be an AP STA or a non-AP STA.

[0208] FIG. 17 is a drawing for explaining the operation of a first STA according to the present disclosure.

[0209] In step S1710, the first STA can receive a protected block ACK request frame from the second STA based on a specific protocol.

[0210] In step S1720, the first STA can generate an AAD based on a block ACK request frame.

[0211] Here, the AAD can be generated based on the plain text of the received block ACK request frame. For example, the AAD can be generated based on information in the plain text state, excluding parts where protection information is located, parts corresponding to the calculation range of the MIC, or encrypted parts within the protected block ACK request frame.

[0212] Additionally, the AAD may be based on one or more fields included in the MAC header of the block ACK request frame. Alternatively, the AAD may be based on one or more subfields included in the MAC header of the block ACK request frame and one or more subfields included in the block ACK request control field of the block ACK request frame. Alternatively, the AAD may be based on one or more subfields included in the MAC header of the block ACK request frame and one or more subfields included in the block ACK request information field of the block ACK request frame.

[0213] According to the present disclosure, if a specific protocol applied to the protection of a block ACK request frame is an integrity protocol such as BIP, an AAD may be configured based on one or more subfields among the fields of the block ACK request frame's MAC header, block ACK request control field, and block ACK request information field, excluding the field where the protection information field (or subfield) is located. For example, the protection information (sub)field may include one or more of a key ID, a packet number (PN), or a message integrity code (MIC).

[0214] Additionally or alternatively, according to the present disclosure, if a specific protocol applied to the protection of a block ACK request frame is an integrity protocol such as BIP, an AAD may be configured based on one or more subfields among the fields excluding one or more fields corresponding to the MIC calculation range among the MAC header, block ACK request control field, and block ACK request information field of the block ACK request frame. For example, the field where the protection information (sub)field is located may correspond to the MIC calculation range.

[0215] For example, if the field corresponding to the MIC calculation range where the protection information (sub)field is located is the block ACK request control field, the AAD may be configured based on one or more subfields included in the MAC header among the remaining fields excluding the block ACK request control field, or the AAD may be configured based on one or more subfields included in the MAC header and one or more subfields included in the block ACK request information field. For example, if the field corresponding to the MIC calculation range where the protection information (sub)field is located is the block ACK request information field, the AAD may be configured based on one or more subfields included in the MAC header among the remaining fields excluding the block ACK request information field, or the AAD may be configured based on one or more subfields included in the MAC header and one or more subfields included in the block ACK request control field. For example, if the field corresponding to the MIC calculation range where the protection information (sub)field is located is neither the block ACK request control field nor the block ACK request information field (e.g., a specific field between the block ACK request information field and the FCS field), the AAD may be configured based on one or more subfields included in the MAC header, which are the remaining fields excluding the block ACK request control field and the block ACK request information field.

[0216] In addition, according to the present disclosure, if a specific protocol applied to the protection of a block ACK request frame is an encryption protocol such as CCMP or GCMP, an AAD may be configured based on whether encryption is applied to one or more of the block ACK request control field or block ACK request information field of the block ACK request frame.

[0217] For example, when encryption is applied to the block ACK request control field and the block ACK request information field, an AAD may be configured based on one or more subfields included in the MAC header. As another example, when encryption is applied to the block ACK request control field, an AAD may be configured based on one or more subfields included in the MAC header, or an AAD may be configured based on one or more subfields included in the MAC header and one or more subfields included in the block ACK request information field. As yet another example, when encryption is applied to the block ACK request information field, an AAD may be configured based on one or more subfields included in the MAC header, or an AAD may be configured based on one or more subfields included in the MAC header and one or more subfields included in the block ACK request control field.

[0218] Additionally, according to the present disclosure, one or more subfields included in each of the MAC header, block ACK request control field, or block ACK request information field of the block ACK request frame may all be included identically in the AAD. Alternatively, some of the subfield(s) may be included identically in the AAD, and certain subfield(s) may be included in the AAD with some or all of their bit values ​​changed / set to 0 (e.g., masked out).

[0219] In this regard, among the subfields included in the MAC header, the subfields used for AAD configuration may be one or more of the Frame Control subfield, the Duration subfield, the Receiver Address (RA) subfield, or the Sender Address (TA) subfield. Additionally, one or more of the subfields of the Frame Control subfield, such as the Protocol Version subfield, Type subfield, Subtype subfield, To DS (Distribution System) subfield, From DS subfield, More Fragments subfield, Retry subfield, Power Management subfield, More Data subfield, Protection Frame subfield, or +HTC subfield, may also be used for AAD configuration.

[0220] Additionally, among the subfields included in the block ACK request control field, the subfield used for AAD configuration may be one or more of the block ACK request type subfield, the TID_INFO subfield, or the subfield(s) corresponding to one or more bit positions among bit position 0 (B0) and B5-B11.

[0221] Additionally, among the subfields included in the block ACK request information field of the compressed block ACK request variant, the extended compressed block ACK request variant, or the GLK-GCR block ACK request variant, the subfield used for AAD configuration may include a block ACK starting sequence control subfield.

[0222] Additionally, among the subfields included in the block ACK request information field of a multiple TID (traffic identifier) ​​block ACK request variant, the subfield used for AAD configuration may be one or more of the per TID info subfield or the block ACK start sequence control subfield.

[0223] In addition, among the subfields included in the block ACK request information field of the GCR block ACK request variant, the subfield used for AAD configuration may be one or more of the block ACK start sequence control subfield or the GCR group address subfield.

[0224] In step S1730, the first STA may perform one or more of decoding or integrity checks on the block ACK request frame.

[0225] In this regard, one or more of decoding or integrity checks for a block ACK request frame may be performed based on key information related to protection for the block ACK request frame and the aforementioned AAD. For example, the block ACK request frame may include information related to a request for a block ACK for data to be received by the second STA. Here, the key information related to protection for the block ACK request frame may be key information distinct from key information for protection of the corresponding data.

[0226] Additionally or alternatively, between the first STA and the second STA (prior to the aforementioned step S1710), instruction information indicating whether protection for a block ACK request frame is supported, the MPDU format of the protected block ACK request frame, or the block ACK request AAD type may be exchanged. Such instruction information may be included, for example, in one or more of a beacon frame, a probe request frame, a probe response frame, a join request frame, a join response frame, a re-join request frame, or a re-join response frame; or included in the block ACK request control field if a specific protocol is an integrity protocol; or included in the block ACK request control field if a specific protocol is an encryption protocol and the block ACK request control field is excluded from encryption; or, if a specific protocol is an encryption protocol, included in the encryption protocol header (e.g., CCMP header, GCMP header) within the block ACK request frame.

[0227] For example, the block ACK request AAD type may indicate a first type in which the AAD is configured based on one or more fields included in the MAC header; a second type in which the AAD is configured based on one or more fields included in the MAC header and one or more fields included in the block ACK request control field; or a third type in which the AAD is configured based on one or more fields included in the MAC header and one or more fields included in the block ACK request information field.

[0228] For example, if a specific protocol is applied to a block ACK request frame, the protected frame subfield within the frame control subfield of the MAC header of the block ACK request frame may be set to a specific value that is predefined. Accordingly, the first STA may also confirm that the block ACK request frame is a protected block ACK request frame.

[0229] The method described in the example of FIG. 17 may be performed by the first device (100) of FIG. 1. For example, one or more processors (102) of the first device (100) of FIG. 1 may be configured to receive a protected block ACK request frame based on a specific protocol through one or more transceivers (106); generate an AAD based on the block ACK request frame; and perform one or more of decoding or integrity checks on the block ACK request frame based on the AAD. Furthermore, one or more memories (104) of the first device (100) may store instructions for performing the method described in the example of FIG. 17 or the examples described below when executed by one or more processors (102).

[0230] FIG. 18 is a drawing for explaining the operation of a second STA according to the present disclosure.

[0231] In step S1810, the second STA can generate an AAD for a block ACK request frame based on a specific protocol.

[0232] Since the generation of an AAD for a block ACK request frame of the second STA, which is the transmitting STA, is the same as the generation of an AAD for a block ACK request frame of the first STA, which is the receiving STA in FIG. 17, a redundant explanation is omitted. For example, if protection based on a specific protocol is applied to a block ACK request frame, an AAD may be generated based on the parts of the protected block ACK request frame where protection information is located, corresponds to the calculation range of the MIC, or where the receiving STA can obtain information in plaintext state excluding the encrypted parts.

[0233] In step S1820, the second STA can transmit a protected block ACK request frame to the first STA based on the AAD.

[0234] The configuration of the protected block ACK request frame and the information transmitted or received between the first STA and the second STA for this purpose are identical to those described in the example of FIG. 17, so redundant descriptions are omitted.

[0235] The method described in the example of FIG. 18 may be performed by the second device (200) of FIG. 1. For example, one or more processors (202) of the second device (200) of FIG. 1 may be configured to generate an AAD for a block ACK request frame based on a specific protocol; and to transmit a protected block ACK request frame based on the AAD through one or more transceivers (206). Furthermore, one or more memories (204) of the second device (200) may store instructions for performing the method described in the example of FIG. 18 or the examples described below when executed by one or more processors (202).

[0236] The examples of FIGS. 17 and 18 may correspond to some of the various examples of the present disclosure. Hereinafter, various examples of the present disclosure including the examples of FIGS. 17 and 18 will be described in more detail.

[0237] Example 1

[0238] This embodiment relates to an AAD configuration method for protecting block ACK request frames.

[0239] In the case of the aforementioned BIP, CCMP, and GCMP, the AAD can be configured based on information included in the MAC header of the transmitted frame.

[0240] In this regard, unlike the MAC header of a standard frame, the MAC header of a block ACK request frame consists of a frame control field, a duration field, a receiver address (RA) field, and a transmitter address (TA) field (see, for example, FIG. 16).

[0241] In the following, specific methods for configuring an AAD when applying BIP, CCMP, and / or GCMP to a block ACK request frame based on the MAC header of the block ACK request frame described above are explained. In configuring an AAD according to the present disclosure, at least one or more of the methods proposed below may be used.

[0242] Example 1-1

[0243] An AAD for protection of a block ACK request frame can be configured by utilizing fields located before the BAR control field within the block ACK request frame.

[0244] Specifically, the AAD can be configured by utilizing the frame control field, duration field, RA field, and / or TA field within the corresponding block ACK request frame.

[0245] FIG. 19 shows examples of AAD configurations for protecting block ACK request frames according to embodiments of the present disclosure.

[0246] Referring to FIG. 19(a), an example is provided in which the AAD is configured to include all four fields, namely the frame control field, the duration field, the RA field, and the TA field, but is not limited thereto. For example, the AAD for a block ACK request frame may be composed only of the frame control field, the RA field, and the TA field.

[0247] In this regard, for the frame control field, the values ​​of the sub-fields may all be included in the AAD, or specific sub-field(s) may be changed / set to 0 (e.g., masked out) and included. For example, the sub-fields of the frame control field may include the protocol version sub-field, type sub-field, subtype sub-field, to DS sub-field, from DS sub-field, more fragments sub-field, retry sub-field, power management sub-field, more data sub-field, protection frame sub-field, +HTC sub-field, etc.

[0248] Examples 1-2

[0249] An AAD for protection of a block ACK request frame can be configured by utilizing fields located before the BAR information field within the block ACK request frame.

[0250] Specifically, the AAD can be configured by utilizing the frame control field, duration field, RA field, and / or TA field within the corresponding block ACK request frame, as well as the BAR control field.

[0251] Referring to FIG. 19(b), an example is provided in which the AAD is configured to include all fields located before the frame control field within a block ACK request frame, but is not limited thereto. For example, the AAD for a block ACK request frame may be composed only of the frame control field, RA field, TA field, and BAR control field.

[0252] Examples of BAR control fields included in the AAD for block ACK request frames are described below, and one of the following examples may be applied, or a combination of multiple examples may be applied.

[0253] For example, the values ​​of all fields within the BAR control field can be included in the AAD without change.

[0254] As another example, some (sub)field(s) value(s) within the BAR control field may be included in the AAD without modification, while all or some bit(s) of other specific (sub)field(s) value(s) may be changed / set to 0 (e.g., masked out) and included in the AAD. Specific bits / (sub)field(s) within the BAR control field that may be changed / set to 0 may include one or more of the following items. Hereinafter, BX refers to the X-th bit position.

[0255] - B0 (Reserved bit)

[0256] - BAR type subfields from B1 to B4

[0257] - (Reserved bits) from B5 to B11

[0258] - TID_INFO subfields from B12 to B15

[0259] Examples 1-3

[0260] An AAD for protection of a block ACK request frame can be configured using fields located before the BAR control field and the BAR information field within the block ACK request frame. For example, an AAD can be configured based on all fields excluding the BAR control field within the block ACK request frame.

[0261] Specifically, the AAD can be configured by utilizing the frame control field, duration field, RA field, and / or TA field within the corresponding block ACK request frame, as well as additionally the BAR information field.

[0262] Referring to FIG. 19(c), an example is provided in which the AAD is configured to include all fields located before the BAR control field within the block ACK request frame and the BAR information field, but is not limited thereto. For example, the AAD for the block ACK request frame may be composed only of the frame control field, the RA field, the TA field, and the BAR information field.

[0263] Various block ACK request variants (or types) identified by a BAR type subfield included in the BAR control field may be defined. For example, the subfields included in the block ACK request frame may differ depending on the extended compressed block ACK request variant, the compressed block ACK request variant, the multiple TID (traffic identifier) ​​block ACK request variant, the GCR (groupcast with retries) block ACK request variant, and the GLK-GCR (general link-groupcast with retries) block ACK request variant. In this disclosure, one or more subfields among the subfields included in the block ACK request frame depending on the block ACK request variant (or type) may be included in the AAD.

[0264] Hereinafter, methods for configuring the BAR information field included in the AAD for the block ACK request frame according to the present disclosure are described, and one of the following methods may be applied, or a combination of multiple methods may be applied.

[0265] (Method 1)

[0266] The values ​​of all (sub)fields included in the BAR information field within the block ACK request frame can be included in the AAD for the block ACK request frame without change.

[0267] The values ​​of all subfields included in the BAR information field of the compressed block ACK request variant (e.g., the 2-octet Block Ack starting sequence control subfield) can be included in the AAD for the block ACK request frame without change.

[0268] The values ​​of all subfields included in the BAR information field of the extended compressed block ACK request variant (e.g., the 2-octet block ACK start sequence control subfield) can be included in the AAD for the block ACK request frame without change.

[0269] The values ​​of all subfields included in the BAR information field of a multi-TID block ACK request variant (e.g., the repeating unit for each TID (the 2-octet per TID info subfield included in one unit, the 2-octet block ACK start sequence control subfield)) can be included in the AAD for the block ACK request frame without change.

[0270] The values ​​of all subfields included in the BAR information field of the GCR block ACK request variant (e.g., the 2-octet block ACK start sequence control subfield, the 6-octet GCR group address subfield) can be included in the AAD for the block ACK request frame without change.

[0271] The values ​​of all subfields included in the BAR information field of the GLK-GCR block ACK request variant (e.g., the 2-octet block ACK start sequence control subfield) can be included in the AAD for the block ACK request frame without change.

[0272] (Method 2)

[0273] The value(s) of some (sub)field(s) of the BAR information field within the block ACK request frame are included in the AAD without modification, and all or some bit(s) of other specific (sub)field(s) value(s) may be changed / set to 0 (e.g., masked out) and included in the AAD. Specific bits / (sub)field(s) within the BAR information field that may be changed / set to 0 may include one or more of the following items.

[0274] In the case of a compressed block ACK request variant, an extended compressed block ACK request variant, or a GLK-GCR block ACK request variant, one or more of the fragment number subfield and the starting sequence number subfield within the Block ACK starting sequence control subfield included in the BAR information field may be included in the AAD for the block ACK request frame with some or all of their bit values ​​changed / set to 0.

[0275] For a multi-TID block ACK request variant, for each TID included in the BAR information field, one or more of the repeating units (the 2-octet TID info subfield included in one unit, the fragment number subfield and the start sequence number subfield within the 2-octet block ACK start sequence control subfield) may be included in the AAD for the block ACK request frame with some / all of their bit values ​​changed / set to 0.

[0276] In the case of a GCR block ACK request variant, one or more of the fragment number subfield and the start sequence number subfield within the 2-octet block ACK start sequence control subfield included in the BAR information field, and the 6-octet GCR group address subfield, may be included in the AAD for the block ACK request frame with some or all of their bit values ​​changed / set to 0.

[0277] Examples 1-4

[0278] This embodiment relates to a signaling method for whether protection (e.g., BIP, CCMP, or GCMP) for block ACK request frames is supported.

[0279] In relation to the application of protection for block ACK request frames according to the present disclosure, the transmitting STA and the receiving STA(s) may share information with each other regarding whether protection for block ACK request frames is supported. Such information may be shared through a specific element (e.g., RSNXE(Extended RSN element)) during the discovery process (e.g., beacon frame, probe response frame, etc.) and / or the (re)combination process (e.g., (re)combination request frame, (re)combination response frame, etc.).

[0280] In this regard, whether protection is supported for block ACK request frames can be shared by utilizing a reserved bit within an existing element (e.g., RSNXE) or by defining a new (sub)field within a new element. For example, a 1-bit protected Block ACK request support (sub)field can be newly defined, and a value of 1 can be defined to mean / indicate that protection is supported for block ACK request frames, and a value of 0 can be defined to mean / indicate that protection is not supported for block ACK request frames.

[0281] If both the sending STA and the receiving STA support protection and support applying protection to block ACK request frames, the two STAs may apply protection to block ACK request frames. Conversely, if the sending STA and the receiving STA support protection but do not support applying protection to block ACK request frames, the two STAs may not apply protection to block ACK request frames. Additionally, when applying protection to block ACK request frames, the same cipher suite agreed upon by the sending STA and the receiving STA during the negotiation process (e.g., CCMP-128, CCMP-256, GCMP-128, GCMP-256, BIP-GMAC-128, BIP-GMAC-256, or BIP-CMAC-256, etc.) may be used. Alternatively, to apply protection to a block ACK request frame, the sending STA and the receiving STA may negotiate an additional / separate cipher suite for the block ACK request frame. Alternatively, protection may be applied to a block ACK request frame not only when both the sending STA and the receiving STA explicitly support applying protection to the block ACK request frame, but also when they imply it without explicitly stating (e.g., when it is indirectly indicated that protection is supported depending on how information related to protection is configured). Alternatively, if there are multiple receiving STAs for a block ACK request frame, the sending STA may apply protection to the block ACK request frame even if some of the STAs support applying protection to the block ACK request frame but some of the STAs do not.

[0282] Additionally or alternatively, in existing wireless LAN systems, for a block ACK request frame, which is a type of control frame, the transmitting STA and the receiving STA do not perform protection actions based on BIP, CCMP, or GCMP. In this regard, the protected frame subfield of the frame control field in the MAC header is set to reserved for control frames.

[0283] In contrast, when BAR control fields and / or BAR information fields are protected by applying BIP, CCMP, or GCMP to a block ACK request frame according to the method proposed in the present disclosure, the value of the protected frame subfield within the frame control field of the block ACK request frame is set to 1. Based on this, the receiving STA can recognize that the BAR control fields and / or BAR information fields within the block ACK request frame are protected through the value of the protected frame subfield. In this regard, when protecting a block ACK request frame, the same cipher suite agreed upon by the sending STA and the receiving STA during the negotiation process (e.g., CCMP-128, CCMP-256, GCMP-128, GCMP-256, BIP-GMAC-128, BIP-GMAC-256, or BIP-CMAC-256, etc.) may be used. Alternatively, to protect the block ACK request frame, the sending STA and the receiving STA may negotiate an additional / separate cipher suite for the block ACK request frame (e.g., CIP (control integrity protocol)-GMAC-128, CIP-GMAC-256, CIP-CMAC-128, CIP-CMAC-256, etc. associated with a separate integrity protocol for the control frame).

[0284] Additionally or alternatively, information regarding whether protection (e.g., BIP, CCPM, or GCMP) is supported for block ACK request frames and AAD configuration methods related to BIP / CCMP / GCMP MPDU formats (e.g., examples in FIG. 19) may be shared between the transmitting STA and the receiving STA. For example, the information regarding AAD configuration methods may be information explicitly indicating an AAD configuration (e.g., information indicating one of the examples in FIG. 19) or information implicitly indicating an AAD configuration.

[0285] In this regard, information implicitly indicating the AAD configuration may be information about the structure of the BIP / CCMP / GCMP MPDU format. For example, in the case of BIP, information implicitly indicating the AAD configuration may be information about the location where protection-related information, including the key ID, PN-related information, and / or MIC, is included within the block ACK request frame. For another example, in the case of CCMP / GCMP, information implicitly indicating the AAD configuration may be information about the location where encryption is applied within the block ACK request frame (e.g., BAR control field and / or BAR information field).

[0286] For the sharing of the aforementioned information, reserved bits within existing elements (e.g., RSNXE), reserved bits within BAR control fields, and / or new (sub)fields within new elements (e.g., BlockAck request AAD type (sub)field or protected BlockAck request mode (sub)field) (hereinafter collectively referred to as BlockAck request AAD type (sub)field for clarity of explanation) may be defined. Such (sub)fields may be included in a beacon frame by the transmitting STA or included in a data frame by the receiving STA during the data transmission and reception process as well as during the (re)assembly process.

[0287] For example, if the value of the block ACK request AAD type (sub)field is set to 0, it may mean / indicate that protection (e.g., BIP, CCMP, or GCMP) is not applied to the block ACK request frame. Conversely, if the value of the block ACK request AAD type (sub)field is set to 1 or higher, it may mean / indicate that protection is applied to the block ACK request frame.

[0288] As a specific example, if the block ACK request AAD type (sub)field is set to a value of 1 or more, the value of the block ACK request AAD type (sub)field may be defined as shown in Table 2 below. Table 1 is illustrative, and at least one of the values ​​described in Table 1 may be applied / defined, and the specific value may be set / defined differently from the example.

[0289] Value of the block ACI request AAD type (sub)field meaning 0 Protection not applied to block ACK request frame 1 AAD configuration for block ACK request frames based on Example 1-1 2 AAD configuration for block ACK request frames based on Examples 1-2 3 AAD configuration for block ACK request frames based on Examples 1-3 ... ...

[0290] Additionally or alternatively, a reserved bit existing at the beginning of the key ID information (i.e., key ID octet) within the CCMP header and / or GCMP header may be utilized as a block ACK request AAD type (sub)field to share information regarding whether protection (e.g., CCMP, or GCMP) is supported for block ACK request frames and the AAD configuration method associated with the BIP / CCMP / GCMP MPDU format (e.g., see examples in FIG. 19). For example, the information regarding the AAD configuration method may be information explicitly indicating the AAD configuration (e.g., information indicating one of the examples in FIG. 19) or information implicitly indicating the AAD configuration.

[0291] In this regard, information implicitly indicating the AAD configuration may be information about the structure of the CCMP / GCMP MPDU format. For example, information implicitly indicating the AAD configuration may be information about the location where encryption is applied within the block ACK request frame (e.g., BAR control field and / or BAR information field).

[0292] Here, the method of encrypting / decrypting the block ACK request frame may use the same cipher suite agreed upon by the sending STA and the receiving STA during the negotiation process (e.g., CCMP-128, CCMP-256, GCMP-128, GCMP-256, BIP-GMAC-128, BIP-GMAC-256, or BIP-CMAC-256, etc.), or may negotiate an additional / separate cipher suite for the block ACK request frame.

[0293] The corresponding (sub)field may be included in a data frame transmitted by the transmitting STA to the receiving STA during the data transmission and reception process.

[0294] As a specific example, if the block ACK request AAD type (sub)field is set to a value of 1 or more, the value of the block ACK request AAD type (sub)field may be defined as shown in Table 2 below. Table 2 is illustrative, and at least one of the values ​​described in Table 2 may be applied / defined, and the specific value may be set / defined differently from the example.

[0295] Value of the (sub)field of the Block ACK Request AAD type meaning 1 AAD configuration for block ACK request frames based on Example 1-1 2 AAD configuration for block ACK request frames based on Examples 1-2 3 AAD configuration for block ACK request frames based on Examples 1-3 ... ...

[0296] Example 2

[0297] This embodiment relates to a specific method for configuring an AAD for a block ACK request frame in relation to the protection application to the aforementioned block ACK request frame.

[0298] First, we will explain the AAD configuration method when applying BIP for protection against block ACK request frames.

[0299] In this regard, the AAD for a block ACK request frame may be configured based on the location where protection information (sub)fields, including information such as key ID, PN (e.g., IPN / BIPN, etc.), and MIC, are included within the block ACK request frame.

[0300] For example, if the protection information (sub)field is located within the BAR information field of the block ACK request frame, the AAD for the block ACK request frame may be configured based on the method of Example 1-1 or Example 1-2 of the present disclosure.

[0301] As another example, if the protection information (sub)field is located within the BAR control field of the block ACK request frame, the AAD for the block ACK request frame may be configured based on the method of Example 1-1 or Example 1-3 of the present disclosure.

[0302] As another example, if the protection information (sub)field is located outside the BAR control field and BAR information field of the block ACK request frame, the AAD for the block ACK request frame may be configured based on the method of Example 1-1 of the present disclosure.

[0303] Referring to the examples above, it may be efficient / desirable for the AAD for a block ACK request frame to be configured based on the remaining field(s), excluding the field where the protection information (sub)field related to the BIP is located or the field(s) corresponding to the calculation range of the MIC within the protection information (sub)field.

[0304] Next, we will explain the AAD configuration method when applying CCMP for the protection of block ACK request frames.

[0305] In this regard, the AAD for the block ACK request frame may be configured based on whether the BAR control field and / or BAR information field is encrypted.

[0306] For example, when CCMP-based encryption is applied to the BAR control field and BAR information field within a block ACK request frame, the AAD for the block ACK request frame may be configured based on the method of Example 1-1 of the present disclosure.

[0307] As another example, when CCMP-based encryption is applied to the BAR control field within a block ACK request frame, the AAD for the block ACK request frame may be configured based on the method of Example 1-1 or Example 1-3 of the present disclosure.

[0308] As another example, when CCMP-based encryption is applied to the BAR information field within a block ACK request frame, the AAD for the block ACK request frame may be configured based on the method of Example 1-1 or Example 1-2 of the present disclosure.

[0309] Referring to the examples above, it may be efficient / desirable for the AAD for the block ACK request frame to be configured based on the remaining field(s) excluding the field(s) to which CCMP-based encryption is applied.

[0310] Next, we will explain the AAD configuration method when applying GCMP for the protection of block ACK request frames.

[0311] In this regard, the AAD for the block ACK request frame may be configured based on whether the BAR control field and / or BAR information field is encrypted.

[0312] For example, when GCMP-based encryption is applied to the BAR control field and BAR information field within a block ACK request frame, the AAD for the block ACK request frame may be configured based on the method of Example 1-1 of the present disclosure.

[0313] As another example, when GCMP-based encryption is applied to the BAR control field within a block ACK request frame, the AAD for the block ACK request frame may be configured based on the method of Example 1-1 or Example 1-3 of the present disclosure.

[0314] As another example, when GCMP-based encryption is applied to the BAR information field within a block ACK request frame, the AAD for the block ACK request frame may be configured based on the method of Example 1-1 or Example 1-2 of the present disclosure.

[0315] Referring to the examples above, it may be efficient / desirable for the AAD for the block ACK request frame to be configured based on the remaining field(s) excluding the field(s) to which GCMP-based encryption is applied.

[0316] Example 3

[0317] This embodiment relates to a specific method for performing protection on a block ACK request frame based on the block ACK request frame configuration proposed in this disclosure.

[0318] For the example situations described below, it is assumed that all transmitting STA and receiving STA(s) support the use of block ACK request frames on BIP, CCMP, or GCMP through a protected block ACK support (sub)field and / or share the configuration method of the BIP, CCMP / GCMP MPDU format within the block ACK request frame through a protected block ACK request mode (sub)field.

[0319] First, the STA operation is described in a situation where all transmitting STA and receiving STA(s) support the application of BIP-based protection to block ACK request frames through the protected block ACK request support (sub)field.

[0320] For example, the receiving STA can construct an AAD for a block ACK request frame based on the information of the block ACK request frame received from the transmitting STA. Subsequently, the receiving STA can calculate a MIC value based on the MPDU using the AAD. At this time, the receiving STA can derive the MIC value by performing the same process that the transmitting STA performed when calculating the MIC value based on the MPDU.

[0321] Subsequently, the receiving STA can compare the derived MIC value with the MIC value transmitted by the transmitting STA (e.g., MIC information included in the protection information (sub)field). If the two MIC values ​​are identical, the receiving STA can follow the information in the acquired MPDU. Conversely, if the two MIC values ​​are not identical, the receiving STA may recognize that at least one piece of information in the acquired MPDU has been altered by a third STA (e.g., an attacking STA) or damaged during transmission and reception, and may discard it.

[0322] Next, the STA behavior is described in a situation where all transmitting STA and receiving STA(s) support CCMP / GCMP-based protection application to block ACK request frames through the protected block ACK request support (sub)field.

[0323] For example, the receiving STA can construct an AAD for a block ACK request frame based on the information in the MAC header of the MPDU received from the transmitting STA (e.g., frame control field, duration field, RA field, TA field, etc.). Subsequently, the receiving STA can use the AAD to proceed with decoding the MSDU.

[0324] The receiving STA can obtain a plaintext MPDU, which is the result of decryption based on the AAD and CCMP configured by itself for a block ACK request frame, and a MIC value based on said MPDU. At this time, the receiving STA can derive the MIC value by performing the same process that the sending STA performed when encrypting said MPDU.

[0325] The receiving STA can compare the derived MIC value with the MIC value transmitted by the transmitting STA (e.g., MIC information included in the CCMP MPDU format or GCMP MPDU format). If the two MIC values ​​are identical, the receiving STA can follow the information in the acquired plaintext MPDU. Conversely, if the two MIC values ​​are not identical, the receiving STA can detect that at least one piece of information in the acquired plaintext MPDU has been altered by a third STA (e.g., an attacking STA) or corrupted during transmission and reception, and can discard it.

[0326] In the case of CCMP where the MIC field is encrypted, the receiving STA can perform an integrity check using the MIC generated / calculated based on the plaintext derived by decrypting the MPDU. In the case of GCMP where the MIC field is not encrypted, the receiving STA can first perform an integrity check using the value of the MIC field of the MPDU, and if the MIC value matches, it can perform decryption of the MPDU.

[0327] The operation of an STA that supports / performs protection for a block-ACK request frame according to an embodiment of the present disclosure may be as shown in FIGS. 20 and FIGS. 21.

[0328] FIG. 20 illustrates the operation of a transmitting STA that supports protection for a block ACK request frame according to the present disclosure.

[0329] Referring to FIG. 20, the transmitting STA may share with the receiving STA information including whether it supports protection (e.g., confidentiality and integrity checks) for block ACK request frames (S2010).

[0330] At this time, when both the transmitting STA and the receiving STA(s) apply security to the block ACK request frame, the transmitting STA may generate and share key(s) used to check the confidentiality and integrity of the block ACK request frame (S2020). In this regard, the transmitting STA and the receiving STA may generate / consult / share the same key information through a key generation process, or the key information generated by the transmitting STA may be transmitted to the receiving STA.

[0331] For example, in connection with the integrity check and / or encryption / decryption of block ACK request frames, key(s) for individually addressed frames (e.g., PTK or BAPTK, collectively referred to as PTK for clarity of description) and / or key(s) for group addressed frames (e.g., GTK, IGTK, BIGTK, or BAGTK, collectively referred to as GTK for clarity of description) may be generated and shared.

[0332] The transmitting STA may construct a block ACK request frame containing information to be shared with the receiving STA(s). Here, the block ACK request frame may be in plaintext form.

[0333] Based on this, the transmitting STA configures an AAD for a block ACK request frame and can apply protection (e.g., BIP, CCMP, or GCMP) to the block ACK request frame based on security key(s) shared with the receiving STA (for the block ACK request frame) (S2030). In this regard, the transmitting STA can derive a MIC value for the block ACK request frame using key(s) shared in advance with the receiving STA.

[0334] The transmitting STA may transmit a block ACK request frame containing result values / information for the application of BIP, CCMP, or GCMP (S2140).

[0335] In relation to the above-described process, the transmitting STA may share or consult with the receiving STA in advance regarding how to configure the CCMP / GCMP MPDU format in the transmitted block ACK request frame, how to configure the AAD for the block ACK request frame, etc., or include such information in the block ACK request frame and transmit it.

[0336] FIG. 21 illustrates the operation of a receiving STA that supports protection for a block ACK request frame according to the present disclosure.

[0337] Referring to FIG. 21, the receiving STA may share information with the sending STA regarding whether it supports protection (e.g., confidentiality and integrity checks) for block ACK request frames (S2110).

[0338] At this time, if the sending STA and the receiving STA share the key(s) used for protection (e.g., confidentiality and integrity check) of the block ACK request frame, the receiving STA can assume that a protection method has been applied to the block ACK request frame transmitted by the sending STA (S2120).

[0339] In this regard, the transmitting STA and the receiving STA may generate / negotiate / share the same key information (e.g., PTK / GTK, etc.) through a key generation process, or the key information generated by the transmitting STA may be transmitted to the receiving STA.

[0340] For example, a receiving STA receives a block ACK request frame transmitted from a transmitting STA and can recognize that protection has been applied to the block ACK request frame based on prior shared key(s), information regarding the configuration of information for integrity checks within the block ACK request frame, the configuration of the CCMP / GCMP MPDU format, and / or information regarding the configuration of the AAD for the block ACK request frame.

[0341] When a block ACK request frame is received, the receiving STA may construct an AAD for the block ACK request frame based on the block ACK request frame. The AAD may be used for decryption and integrity verification. Subsequently, the receiving STA may perform decryption and / or integrity verification on the block ACK request frame using the constructed AAD and (previously) shared / generated / agreed key(s) (e.g., PTK / GTK, etc.) (S2130).

[0342] Afterwards, the receiving STA can perform an integrity check by comparing the MIC value derived based on the decoded block ACK request frame with the MIC value transmitted by the transmitting STA (e.g., MIC information / value included in the block ACK request frame) (S2140).

[0343] Protocols such as BIP / CCMP / GCMP used in existing wireless LAN systems cannot provide protection for control frames such as block ACK frames. The present disclosure provides a new method for configuring an AAD used for transmitting or receiving protected control frames when protocols such as BIP / CCMP / GCMP are applied to control frames such as block ACK frames.

[0344] The embodiments described above are combinations of the components and features of the present disclosure in a specific form. Each component or feature should be considered optional unless otherwise explicitly stated. Each component or feature may be implemented in a form not combined with other components or features. Additionally, it is possible to construct embodiments of the present disclosure by combining some components and / or features. The order of operations described in the embodiments of the present disclosure may be changed. Some components or features of one embodiment may be included in another embodiment, or may be replaced with corresponding components or features of another embodiment. It is obvious that embodiments may be constructed by combining claims that are not explicitly related in the claims, or that they may be included as new claims by amendment after filing.

[0345] It is obvious to those skilled in the art that the present disclosure may be embodied in other specific forms without departing from the essential features of the present disclosure. Accordingly, the detailed description set forth above should not be interpreted restrictively in all respects and should be considered exemplary. The scope of the present disclosure shall be determined by a reasonable interpretation of the appended claims, and all modifications within the equivalent scope of the present disclosure are included within the scope of the present disclosure.

[0346] The scope of the present disclosure includes software or machine-executable instructions (e.g., operating systems, applications, firmware, programs, etc.) that enable operations according to the methods of various embodiments to be executed on a device or computer, and a non-transitory computer-readable medium on which such software or instructions, etc. are stored and executable on a device or computer. Instructions that may be used to program a processing system to perform the features described in the present disclosure may be stored on or within a storage medium or a computer-readable storage medium, and the features described in the present disclosure may be implemented using a computer program product comprising 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 memory devices, and may include non-volatile memory such as one or more magnetic 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(s). Memory or alternatively, non-volatile memory device(s) within memory comprises a non-transient computer-readable storage medium. The features described in this disclosure may be stored in any one of the machine-readable media and integrated into software and / or firmware that can control the hardware of a processing system and allow the processing system to interact with other mechanisms utilizing results according to the 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. Industrial applicability

[0347] Although the method proposed in this disclosure has been described with an example applied to an IEEE 802.11-based system, it can be applied to various wireless LANs or wireless communication systems in addition to IEEE 802.11-based systems.

Claims

Claim 1 A method comprising: receiving a block ACK (acknowledgement) request frame protected based on a specific protocol from a second STA by a first station (STA); generating additional authentication data (AAD) based on the block ACK request frame by the first STA; and performing one or more of decoding or integrity checks on the block ACK request frame by the first STA based on the AAD, wherein the AAD is based on one or more fields included in a medium access control (MAC) header of the block ACK request frame, or based on one or more subfields included in the MAC header and one or more subfields included in the block ACK request control field or block ACK request information field of the block ACK request frame. Claim 2 A method according to claim 1, wherein one or more of the decoding or integrity check of the block ACK request frame is performed based on key information related to protection of the block ACK request frame and the AAD. Claim 3 A method according to claim 1, wherein, based on the fact that the specific protocol is an integrity protocol, the AAD is configured based on one or more subfields among the MAC header, the block ACK request control field, and the block ACK request information field, excluding the field where the protection information field is located. Claim 4 A method according to paragraph 3, wherein the protection information field comprises one or more of a key ID (identifier), a packet number (PN), or a message integrity code (MIC). Claim 5 A method according to claim 1, based on the fact that the specific protocol is an encryption protocol: wherein the AAD is configured based on whether encryption is applied to one or more of the block ACK request control field or the block ACK request information field. Claim 6 A method according to claim 5, wherein the AAD is configured based on one or more subfields included in the MAC header, based on encryption being applied to the block ACK request control field and the block ACK request information field. Claim 7 A method according to claim 5, wherein, based on encryption being applied to the block ACK request control field, the AAD is configured based on one or more subfields included in the MAC header, or is configured based on one or more subfields included in the MAC header and one or more subfields included in the block ACK request information field. Claim 8 A method according to claim 5, wherein, based on encryption being applied to the block ACK request information field, the AAD is configured based on one or more subfields included in the MAC header, or is configured based on one or more subfields included in the MAC header and one or more subfields included in the block ACK control field. Claim 9 In claim 1, one or more subfields included in each of the MAC header, the block ACK request control field, or the block ACK request information field are identically included in the AAD. Claim 10 A method according to claim 1, wherein some or all bit values ​​of a specific one or more subfields among one or more subfields included in each of the MAC header, the block ACK request control field, or the block ACK request information field are set to 0 and included in the AAD. Claim 11 A method according to claim 1, wherein one or more subfields included in the MAC header include one or more of a frame control subfield, a duration subfield, a receiver address (RA) subfield, or a sender address (TA) subfield. Claim 12 A method according to claim 1, wherein one or more subfields included in the block ACK request control field include one or more of the block ACK request type subfield, TID_INFO subfield, or one or more subfields corresponding to one or more bit positions among bit position 0 (B0) and B5-B11. Claim 13 The method of claim 1, wherein one or more subfields included in the block ACK request information field comprise: a block ACK starting sequence control subfield associated with a compressed block ACK request variant, an extended compressed block ACK request variant, or a GLK-GCR (general link-groupcast with retries) block ACK request variant; a per TID info subfield and a block ACK starting sequence control subfield associated with a multiple TID (traffic identifier) ​​block ACK request variant; and one or more of a block ACK starting sequence control subfield and a GCR group address subfield associated with a GCR block ACK request variant. Claim 14 A method according to claim 1, wherein information regarding one or more of the following is exchanged between the first STA and the second STA: whether protection for the block ACK request frame is supported, the MPDU (MAC protocol data unit) format of the protected block ACK request frame, or the block ACK request AAD type. Claim 15 A method according to claim 14, wherein the information is included in one or more of a beacon frame, a probe request frame, a probe response frame, a combination request frame, a combination response frame, a re-combination request frame, and a re-combination response frame, or is included in the block ACK request control field based on the fact that the specific protocol is an integrity protocol, or is included in the block ACK request control field based on the fact that the specific protocol is an encryption protocol and the block ACK request control field is excluded from encryption, or is included in the encryption protocol header within the block ACK request frame based on the fact that the specific protocol is an encryption protocol. Claim 16 A method according to claim 14, wherein the block ACK request AAD type indicates one of: a first type configured based on one or more fields included in the MAC header; a second type configured based on one or more fields included in the MAC header and one or more fields included in the block ACK request control field; or a third type configured based on one or more fields included in the MAC header and one or more fields included in the block ACK request information field. Claim 17 A method according to claim 1, wherein, based on the application of the specific protocol to the block ACK request frame, the protected frame subfield within the frame control subfield of the MAC header is set to a predefined specific value. Claim 18 A 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 related to protection for the block ACK request frame is distinguished from the key information for protection of the data. Claim 19 A device comprising: one or more transceivers; and one or more processors connected to the one or more transceivers, wherein the one or more processors are configured to: receive a block ACK (acknowledgement) request frame protected based on a specific protocol through the one or more transceivers; generate additional authentication data (AAD) based on the block ACK request frame; and perform one or more of decoding or integrity checks on the block ACK request frame based on the AAD, wherein the AAD is based on one or more fields included in the MAC (medium access control) header of the block ACK request frame, or one or more subfields included in the MAC header, and one or more subfields included in the block ACK request control field or block ACK request information field of the block ACK request frame. Claim 20 A method comprising: a step of generating additional authentication data (AAD) for a block ACK (acknowledgement) request frame based on a specific protocol by a second station (STA); and a step of transmitting a block ACK request frame protected based on the AAD to a first STA by the second STA, wherein the AAD is based on one or more fields included in a medium access control (MAC) header of the block ACK request frame, or one or more subfields included in the MAC header, and one or more subfields included in a block ACK request control field or a block ACK request information field of the block ACK request frame. Claim 21 A device comprising: one or more transceivers; and one or more processors connected to the one or more transceivers, wherein the one or more processors: generate additional authentication data (AAD) for a block ACK (acknowledgement) request frame based on a specific protocol; and are configured to transmit a protected block ACK request frame through the one or more transceivers based on the AAD, wherein the AAD is based on one or more fields included in the MAC (medium access control) header of the block ACK request frame, or one or more subfields included in the MAC header, and one or more subfields included in the block ACK request control field or block ACK request information field of the block ACK request frame. Claim 22 A processing device comprising: one or more processors; and one or more computer memories operably connected to the one or more processors and storing instructions for performing a method according to any one of claims 1 to 18 based on execution by the one or more processors. Claim 23 One or more non-transitory computer-readable media storing one or more instructions that are executed by one or more processors to control the execution of a method according to any one of claims 1 through 18.

Images