Privacy management method and device in wireless network

Abstract

The present invention relates to a method for managing a privacy level in a wireless network, the wireless network comprising an access point (AP) station and at least one non-AP station, the method comprising: transmitting, with a first station (non-AP station or AP station), a message comprising information indicating a set of privacy enhancement (PE) parameters to be obfuscated to a second station, the PE parameter set corresponds to a privacy level requested by the first station, if the first station is a non-AP station, the second station is an AP, and if the first station is an AP, the second station is a non-AP station; and receiving a response from the second station indicating whether the second station accepts the requested privacy level.

Description

Technical Field

[0001] The present disclosure relates to methods and apparatus for managing privacy in wireless networks. More particularly, the present disclosure relates to managing privacy profiles during wireless communications. Background Art

[0002] The methods described in this section may be practiced, but they are not necessarily methods that have been previously conceived or practiced. Therefore, unless otherwise indicated herein, the methods described in this section are not prior art with respect to the claims of this application and are not considered prior art because they are included in this section. In addition, all embodiments are not necessarily intended to solve all or even any of the problems raised in this section.

[0003] Wireless communication networks are widely deployed to provide various communication services such as voice, video, packet data, messaging, broadcast, etc. These wireless networks may be multiple access networks capable of supporting multiple users by sharing available network resources. Examples of such multiple access networks include code division multiple access (CDMA) networks, time division multiple access (TDMA) networks, frequency division multiple access (FDMA) networks, orthogonal FDMA (OFDMA) networks, and single carrier FDMA (SC-FDMA) networks. The 802.11 family of standards adopted by the Institute of Electrical and Electronics Engineers (IEEE) provides a number of mechanisms for wireless communication between stations.

[0004] Today, the evolution of wireless systems, driven by user demand and the requirements of the General Data Protection Regulation (GDPR), has brought privacy issues to the forefront. The global wireless industry faces a growing demand to protect users’ personally identifiable information from increasingly sophisticated tracking and profiling activities while continuously improving wireless services and user experience.

[0005] In the context of Wi-Fi networks, the media access control (MAC) address or EUI-48 address of a user device has been quickly identified as a key privacy parameter that can be used to track a user without user consent. The IEEE 802.11 working group then proposed a process that includes dynamically modifying the MAC address of a user device. This mechanism (known as the Random Change MAC (RCM) process) was originally introduced in the 802.11aq Pre-Association Service Discovery Task Group as a privacy enhancement feature and was eventually incorporated into the IEEE Std 802.11-2020 standard. The RCM process is an obfuscation process applied to MAC addresses. It includes periodically changing the MAC address of a non-AP station (STA) (i.e., a station that is not an access point) to a random value when the non-AP station is not associated with the network (or equivalently, not associated with an access point).

[0006] Changing only the MAC address is the first step to improve privacy, but this is usually not enough, and other elements called personally identifiable information (PII) or privacy parameters should also be obfuscated. Obfuscation is usually performed by dynamically modifying the parameter so that the parameter cannot be identified and / or tracked. For example, for the RCM process specified in the IEEE Std802.11-2020 standard, whenever the MAC address of a non-AP STA is changed to a new random value, the counters in all sequence number (SN) spaces used to identify each transmission frame (MSDU or MMPDU) and the scrambler seed used at the PHY layer to scramble the frame data payload before transmission should be randomly reset.

[0007] Since 2019, a specific IEEE 802.11bi task group has been responsible for proposing new technical features beyond the RCM process to enhance privacy in 802.11. At the current stage, the task group specifies a set of privacy requirements that imply new privacy parameters related to AP and / or non-AP STAs (which are called privacy enhancement (PE) parameters) are considered with or without associating non-AP STAs, and means that these multiple PE parameters should be obfuscated at the same time. This may lead to unacceptable implementation costs and complexity. It is expected that the handling of PE parameters will be managed in the BSS to ensure communication at the desired privacy level while reducing implementation costs and complexity. Summary of the invention

[0008] The present invention has been designed to address one or more of the foregoing problems.

[0009] According to a first aspect of the present invention, there is provided a method for managing a privacy level in a wireless network, the wireless network comprising an access point station (AP station) and at least one non-AP station, the method comprising: using a first station that is a non-AP station or an AP station,

[0010] - sending a message including information indicating a privacy enhancement parameter set, PE parameter set, to be obfuscated to the second station, the PE parameter set corresponding to the privacy level requested by the first station; and

[0011] - receiving a response from the second station indicating whether the second station accepts the requested privacy level.

[0012] In an embodiment, the message further comprises an indication of PE parameters supported by the first station.

[0013] In an embodiment, the information indicating the PE parameter set is an information element including, for each possible PE parameter, an indication of whether the PE parameter belongs to a PE parameter set corresponding to the requested privacy level.

[0014] In an embodiment, the information indicating the PE parameter set is an information element including, for at least one privacy profile, whether the privacy profile corresponds to a requested privacy level, wherein the privacy profile corresponds to the PE parameter set.

[0015] In an embodiment, the message further comprises a privacy alignment indication for indicating whether the requested privacy level must be applied to stations belonging to a group of stations connected to the AP station.

[0016] In an embodiment, the group of stations connected to the AP station includes all stations connected to the AP station.

[0017] In an embodiment, the first station is a non-AP station, the message is a management frame sent during association of the non-AP station, and the method further comprises:

[0018] - receiving a message from the AP station indicating a rejection of association if the AP does not accept the requested privacy level.

[0019] In the example:

[0020] - the first station is a non-AP station;

[0021] - the privacy alignment indication is used to indicate that the requested privacy level must be applied to the group of stations; and

[0022] The method further comprises: utilizing the AP station,

[0023] - broadcasting a message requesting the requested privacy level to all stations in the station group.

[0024] In an embodiment, the method further comprises: utilizing the AP station,

[0025] - In case at least one station in said group of stations cannot satisfy the requested privacy level, denying association of said first station.

[0026] In an embodiment, the method further comprises: utilizing the AP station,

[0027] - disassociating stations in the station group that cannot meet the requested privacy level; and

[0028] - accepting the association of said first station.

[0029] In the example:

[0030] - the first station is the AP station; and

[0031] - The message is an action frame.

[0032] In an embodiment, the method further comprises:

[0033] - disassociating said second station in case said second station cannot meet the requested privacy level.

[0034] According to another aspect of the present invention, there is provided a method for managing a privacy level in a wireless network, the wireless network comprising an access point station (AP station) and at least one non-AP station, the method comprising: utilizing a station that is a non-AP station or an AP station,

[0035] - Sending a message including information indicating the privacy enhancing parameter sets, i.e., PE parameter sets, supported by the station to other stations.

[0036] According to another aspect of the present invention, a computer program product is provided for a programmable device, the computer program product comprising an instruction sequence for implementing the method according to the present invention when the instruction sequence is loaded into and executed by the programmable device.

[0037] According to another aspect of the present invention, a computer-readable storage medium is provided, which stores computer program instructions for implementing the method according to the present invention.

[0038] According to another aspect of the invention, there is provided a computer program which, when executed, causes the method according to the invention to be performed.

[0039] According to another aspect of the present invention, a first station device is provided for managing a privacy level in communication with a second station in a wireless network, wherein the wireless network includes access point stations (AP stations) and non-AP stations, the first station device is the non-AP station or the AP station, and the first station device includes a processor, wherein the processor is configured to:

[0040] - sending a message including information indicating a privacy enhancement parameter set, i.e., a PE parameter set, to be obfuscated to the second station, the PE parameter set corresponding to the privacy level requested by the first station; and - receiving a response from the second station indicating whether the second station accepts the requested privacy level.

[0041] According to another aspect of the present invention, a station device is provided for managing a privacy level in a wireless network, wherein the wireless network includes an access point station (AP station) and at least one non-AP station, the station device is a non-AP station or an AP station, and the station device includes a processor, wherein the processor is configured to:

[0042] - Sending a message including information indicating the privacy enhancing parameter sets, i.e., PE parameter sets, supported by the station to other stations.

[0043] According to another aspect of the present invention, there is provided a privacy information element that can be inserted into a message for managing a privacy level in a wireless network, the wireless network comprising an access point station (AP station) and at least one non-AP station, wherein:

[0044] - The privacy information element includes information for indicating the privacy enhanced parameter sets (PE parameter sets) supported by the station and / or to be obfuscated.

[0045] In an embodiment, the privacy information element includes the following status for each PE parameter, and the status includes:

[0046] - A capability field, used to indicate whether the PE parameter is supported; and

[0047] - Enable field, used to indicate whether to obfuscate the PE parameters.

[0048] In an embodiment, the private information element includes a configuration file identifier, the configuration file corresponds to a PE parameter set, and the private information element includes the following status for the configuration file, the status including:

[0049] - A capability field, used to indicate whether the PE parameter is supported; and

[0050] - Enable field, used to indicate whether to obfuscate the PE parameters.

[0051] According to another aspect of the present invention, there is provided a privacy information element that can be inserted into a message for managing a privacy level in a wireless network, the wireless network comprising an access point station (AP station) and at least one non-AP station, wherein:

[0052] -The private information element includes a PE parameter set and a profile identifier for defining a profile corresponding to the PE parameter set.

[0053] At least a portion of the method according to the present invention may be computer-implemented. Therefore, the present invention may take the form of a complete hardware implementation, a complete software implementation (including firmware, resident software, microcode, etc.), or a combination of software and hardware implementations, which may all be collectively referred to herein as "circuit", "module" or "system". In addition, the present invention may take the form of a computer program product, which is implemented in any tangible expression medium having a computer-usable program code implemented in the medium.

[0054] Since the present invention can be implemented in software, the present invention can be implemented as computer readable code on any suitable carrier medium for providing to a programmable device. Tangible non-transitory carrier media may include storage media such as floppy disks, CD-ROMs, hard disk drives, magnetic tape devices, or solid-state memory devices. Transient carrier media may include signals such as electrical signals, electronic signals, optical signals, acoustic signals, magnetic signals, or electromagnetic signals (e.g., microwave or RF signals). BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Embodiments of the present invention will now be described, by way of example only, with reference to the following drawings, in which:

[0056] Figure 1 shows an example of a network system in which embodiments of the present invention may be used;

[0057] Figure 2a , Figure 2b , Figure 2c and Figure 2d The frame format representing PE parameters in an embodiment of the present invention is shown;

[0058] Figure 3a and Figure 3b The main steps of the method for operating an association process including privacy features in an embodiment of the present invention are shown;

[0059] Figure 3c A table showing error return codes associated with an association process including a privacy feature in an embodiment of the present invention is shown;

[0060] Figure 4 shows the frame format representing an action frame;

[0061] Figure 5a and Figure 5b Showing main steps of a method for operating a method for modifying a privacy level by a non-AP STA in an embodiment of the present invention;

[0062] Figure 6 shows the main steps for operating a method for modifying a privacy level by an AP in an embodiment of the present invention; and

[0063] Figure 7 An example of a communication device configured to implement a wireless network of at least one embodiment of the present invention is shown. DETAILED DESCRIPTION

[0064] According to an embodiment, the present invention proposes a global process for sharing their PE parameters between non-AP STAs and APs during the association process. According to an embodiment, a station (AP station or non-AP station) can request a change in privacy level after association. According to an embodiment, a station (AP station or non-AP station) can request the entire BSS or a group of stations in the BSS to adopt a certain privacy level.

[0065] These procedures allow agreement to be reached on a set of PE parameters to be applied between AP and non-AP stations. The set of PE parameters corresponds to the level of privacy that a non-AP or AP station may require.

[0066] Herein, if a station (AP station or non-AP station) is able to apply an obfuscation process to a PE parameter, it is said that the station supports the PE parameter. If a station activates an obfuscation process for a PE parameter, it is said that the PE parameter is enabled. For example, if an AP station is able to cope with obfuscation of a MAC address of the AP station, it is said that the AP station supports the PE parameter corresponding to the MAC address of the AP station.

[0067] Similarly, where a station (AP station or non-AP) is able to cope with obfuscation applied to PE parameters by other stations, the station is said to support the PE parameters of the other stations. For example, where an AP station is able to cope with obfuscation applied to the MAC address of the non-AP station by a non-AP station, the AP station is said to support the PE parameters corresponding to the MAC address of the non-AP station.

[0068] The AP and the non-AP stations associated with the AP need to agree on the PE parameter set used in their communication. First, the AP and the non-AP stations can share their capabilities, such as related to the supported PE parameters, during the association phase. The result of the sharing can be an agreement on the PE parameter set supported by both the AP and the non-AP stations. The result can also be that a common PE parameter set is not supported. Note that as long as the AP does not need to enable PE parameters that the non-AP station does not support (i.e., the non-AP station cannot handle), the non-AP station can still associate with the AP. Second, the AP and the non-AP stations can negotiate the PE parameters to be enabled for communication during the association phase or when the two stations are already associated.

[0069] The IEEE 802.11bi task group has specified two PE feature sets. The first PE feature set, which is called the Client Privacy Enhancement (CPE) feature set, prevents the identification and tracking of clients (non-AP STAs). The second PE feature set, which is called the BSS Privacy Enhancement (BPE) feature set, prevents the identification and tracking of BSSs. Thus, an AP with CPE capability is called a CPE AP, and a non-AP STA with CPE capability is called a CPE non-AP STA or a CPE client. Similarly, an AP with BPE capability is called a BPE AP, and a non-AP STA with BPE capability is called a BPE non-AP STA or a BPE client.

[0070] Typically, a CPE feature is initiated by a CPE client (which is referred to as the initiating CPE client), and a BPE feature is initiated by a BPE AP. A CPE feature involves simultaneously obfuscating multiple PE parameters (which are referred to as CPE parameters). Similarly, a BPE feature involves simultaneously obfuscating multiple PE parameters (which are referred to as BPE parameters). In this way, each PE parameter is obfuscated by a non-AP station or an AP station according to a dedicated obfuscation process associated with that PE parameter. The obfuscation process generally implies random changes in the parameters, but it can be different depending on the nature of the PE parameters.

[0071] In this document, PE parameters refer indiscriminately to CPE parameters and / or BPE parameters. The details of the obfuscation process associated with each PE parameter are beyond the scope of this document.

[0072] For illustration, the CPE parameters currently identified by the IEEE 802.11bi task group are as follows:

[0073] The MAC address of the CPE client for over-the-air (OTA) communication (which is referred to as the OTA MAC address), which is indicated in the sender address (TA) field or the receiver address (RA) field (corresponding to address 2 or address 3) of the IEEE802.11 frame. Optionally, the CPE client may have several OTA MAC addresses, each for a given purpose (data, measurement, etc.). The MAC address (or EUI-48 address) of the device is an extended unique identifier (EUI) consisting of 48 bits. The address can be globally managed or locally managed. The globally managed address is uniquely assigned to the device by the manufacturer. In contrast, the locally managed address is assigned to the device by software or a network administrator and replaces the physically burned address. The second least significant bit of the first octet of the MAC address (i.e., the seventh bit of the address, also called the "U / L bit" (i.e., the "Universal / Local bit")) indicates whether the address is globally managed (when set to 0) or locally managed (when set to 1). The least significant bit of the first octet of the MAC address (i.e., the eighth bit of the address, also known as the "I / G bit" (i.e., "Individual / Group bit")) indicates whether the frame is sent to only one receiving device (when set to 0, indicating unicast transmission) or to multiple devices (when set to 1, indicating multicast transmission).

[0074] Sequence Number (SN), which is included in the Sequence Number field of the Sequence Control field of the MAC header of an 802.11 frame (MSDU, A-MSDU, or MMPDU). The sequence number is a 12-bit field. The sequence number is incremented for each frame transmission and remains unchanged in case of frame retransmission.

[0075] The packet number (PN) is included in the packet number field of the CCMP header of the plaintext MAC payload of the frame. The packet number is a 48-bit packet number. The packet number is used for encryption of the frame and allows the frame being transmitted to be uniquely identified for replay detection. The packet number is incremented for each frame transmission and remains unchanged in the event of a frame retransmission.

[0076] Association Identifier AID (AID), which is a unique identifier assigned by the AP to a non-AP during association. The association identifier is a 16-bit field and is included in many frames for different purposes, such as power saving or allocating resources in MU OFDMA.

[0077] Scrambler Seed, which corresponds to the seed used by the PLCP / OFDM PHY DATA scrambler to initialize its initial state (802.11-2020 - subclause 17.3.5.5). The scrambler seed corresponds to a 7-bit parameter.

[0078] For BPE clients, the BPE parameters are the same as the CPE parameters. For BPE APs, the IEEE 802.11bi task group identifies the following:

[0079] OTA MAC address of the BPE AP, which is indicated in the Transmitter Address (TA) field or the Receiver Address (RA) field (corresponding to Address 2 or Address 3) of the IEEE 802.11 frame. Optionally, a BPE AP may have several OTA MAC addresses, each for a given purpose (data, measurement, etc.).

[0080] Scrambler Seed, which corresponds to the seed used by the PLCP / OFDM PHY DATA scrambler to initialize its initial state (802.11-2020 - subclause 17.3.5.5). The scrambler seed corresponds to a 7-bit parameter.

[0081] Beacon Interval, which corresponds to the difference between two target beacon transmission times (TBTT), which is the time at which the AP should send its beacon frame. The beacon interval is given in time units (TU), with one TU equal to 1024 microseconds. The beacon interval is a 16-bit field set to the number of TUs between beacon transmissions and is included in the Beacon Interval field of the beacon frame.

[0082] Obviously, the CPE / BPE parameters listed above are not exhaustive, and other CPE / BPE parameters may also be considered. For example, as a BPE parameter, the BSS color for identifying the BSS introduced by the IEEE 802.11ax task group may also be considered. The BSS color is included in the BSS color field of the BSS color information of the HE operation element, wherein the HE operation element is included in the beacon frame, the probe response frame and the (re) association frame. The BSS color is a 6-bit parameter.

[0083] Figure 1An 802.11 network (i.e., Wi-Fi network) system 100 is shown, which includes four wireless devices: an access point (AP) 110 and three non-AP stations (non-AP STAs) 120a, 120b, and 120c. Of course, the number of non-AP STAs 120a, 120b, and 120c may not be three. AP 110 provides wireless connection between non-AP STAs 120a, 120b, and 120c and a wider network such as the Internet. The connection of non-AP STAs 120a, 120b, and 120c to AP 110 is performed through a standardized process called association. Once non-AP STAs 120a, 120b, and 120c are associated with AP 110, non-AP STAs 120a, 120b, and 120c can send and receive data relative to the network through AP 110.

[0084] The AP 110 may include, be implemented as, or be known as a Node B, a radio network controller (RNC), an evolved Node B (eNB), a 5G next generation base station (gNB), a base station controller (BSC), a base transceiver station (BTS), a base station (BS), a transceiver function (TF), a radio router, a radio transceiver, a basic service set (BSS), an extended service set (ESS), a radio base station (RBS), or some other terms. The AP 110 may be an independent product, or may be integrated in a device such as a broadband remote access server (BRAS).

[0085] The non-AP STA 120a, 120b, 120c may include, be implemented or known as a subscriber station, a subscriber unit, a mobile station (MS), a remote station, a remote terminal, a user terminal (UT), a user agent, a user device, a user equipment (UE), a user station or some other term. In some implementations, the non-AP STA 120a, 120b, 120c may be or may include a cellular phone, a cordless phone, a session initiation protocol (SIP) phone, a wireless local loop (WLL) station, a personal digital assistant (PDA), a handheld device with wireless connection capability, or some other suitable processing device connected to a wireless modem. Therefore, one or more aspects taught herein may be incorporated into a phone (e.g., a cellular phone or a smart phone), a computer (e.g., a laptop computer), a tablet computer, a portable communication device, a portable computing device (e.g., a personal data assistant), an entertainment device (e.g., a music or video device, or a satellite radio), a global positioning system (GPS) device, or any other suitable device configured to communicate via a wireless or wired medium. In some aspects, the non-AP STAs 120a, 120b, 120c may be wireless nodes. Such wireless nodes may provide connectivity for or to a network (eg, a wide area network such as the Internet or a cellular network) via a wired or wireless communication link.

[0086] The AP 110 manages a group of STAs that organize their access to the wireless medium together for communication purposes. All STAs (AP 110 and non-AP STAs 120a, 120b, 120c) form a service set, which can be called a basic service set (BSS), but other terms can also be used. It should be noted that the AP 110 can manage more than one BSS: each BSS is thus uniquely identified by a specific basic service set identifier (BSSID) and managed by a separate virtual AP implemented in the physical AP 110.

[0087] To ensure user privacy, the AP STA 110 and the non-AP STAs 120a, 120b, 120c have been configured with dot11MACPrivacyActivated set to true. This is a management information base (MIB) variable that can be controlled by an external management entity to define whether the non-AP STA can apply a specific mechanism for enhancing the privacy of the MAC layer (the mechanism includes the RCM process), wherein the mechanism can be applied when the variable is set to true, and the mechanism cannot be applied when the variable is set to false.

[0088] According to some embodiments of the present invention, the AP STA 110 is a CPE AP, and the non-AP STAs 120a, 120b, 120c are CPE clients. According to other embodiments of the present invention, the AP STA 110 is a BPE AP, and the non-AP STAs 120a, 120b, 120c are BPE clients. According to other embodiments, the AP STA 110 is both a CPE AP and a BPE AP, and the non-AP STAs 120a, 120b, 120c are both CPE clients and BPE clients.

[0089] Figure 2a , Figure 2b , Figure 2c and Figure 2d A frame format representing a privacy parameter according to an embodiment of the present invention is shown.

[0090] Figure 2a In one embodiment, an information element (IE) dedicated to managing all privacy enhancement (PE) parameters (CPE or BPE) is shown. The information element (IE) can be included in any management frame, such as the frames used during the association process. The privacy IE 200 allows the state of each PE parameter to be defined taking into account the station's ability to handle the PE parameter and an enablement state indicating whether obfuscation of the PE parameter is activated.

[0091] Privacy IE 200 includes:

[0092] Element ID 201, which identifies the information element;

[0093] Length field 202, which defines the length of the information element;

[0094] Element ID extension field 203, which identifies the extended information element;

[0095] A Privacy Alignment field 210, which may be used by a non-AP STA to request the AP to force all other associated non-AP STAs to support at least the same PE parameters;

[0096] • Privacy fields 220, 221, 222, 223, which define the state of PE parameters, such as the OTA MAC address, sequence number, packet number, scrambler seed, and any other PE parameters, respectively. Figure 2c The states of the PE parameters include:

[0097] - "Capability" field, which is set to 1 if the non-AP STA or AP supports the PE parameter, otherwise it is set to 0;

[0098] - An "Enable" field, which is set to 1 if the non-AP STA or AP requires or confirms obfuscation of PE parameters, otherwise 0. In some embodiments, a value of 0 may also be used to require or confirm stopping obfuscation if obfuscation is already activated.

[0099] Figure 2b Another embodiment of the privacy IE 230 is shown. For this embodiment, the privacy fields 220, 221, 222, 223 that describe the state of a PE parameter are replaced by privacy profile fields 231, 232, 233. Each privacy profile field is associated with a privacy profile corresponding to a PE parameter set. Figure 2d As detailed, the privacy profile can be predefined or dynamically defined. This embodiment is particularly useful in the context of the WiFi Alliance, which often specifies predefined profiles for STAs. It allows for a one-time management of a set of predefined PE parameters corresponding to a profile. Thus, it is easier to manage each PE parameter independently. Figure 2a This embodiment is generally more compact than the first embodiment of the present invention. This embodiment allows reducing the overhead of the previous embodiment by defining several privacy profiles. The privacy profile field is also represented by Figure 2c The same subfields used to manage the capabilities and enabled status of privacy profiles as shown in . If a station can handle obfuscation of all PE parameters in the PE parameter set corresponding to a profile, the station is said to support the profile. If obfuscation of all PE parameters of a profile is enabled (meaning that obfuscation of all PE parameters of the profile is activated), the station is said to have enabled the profile.

[0100] Figure 2d An embodiment of an information element (IE) dedicated to defining a privacy profile is shown. The privacy profile set IE 250 defines which PE parameters 270, 271, 272, 273, 274, 275, 276 are included in the profile, and associates the set of PE parameters with a profile number (or identifier) ​​260. As with any information element defined by the 802.11 standard, this IE can be included in any management frame or action frame. Management frames are frames used to manage the BSS. Action frames are management frames that trigger actions to occur. APs can use these privacy profile set IEs 250 to advertise valid privacy profiles for the BSS to all associated non-AP STAs. The AP can then use the verified privacy profiles to communicate with the BSS by using, for example, Figure 2b The information elements shown are used to manage the set of verified privacy profiles. These information elements 2b and 2d allow the definition and use of any profile beyond the predefined profiles.

[0101] Figure 3a and Figure 3b The main steps of the method for operating the association process implying privacy features in an embodiment of the present invention are shown. Figure 2a to Figure 2d Examples of the use of the described information elements. The AP and STA may use the association process to share their capabilities and find consensus on the enabled features of each part.

[0102] Associations include Figure 3a and Figure 3b Three main parts are shown: Probe Exchange, Authentication Exchange, and Association Exchange.

[0103] In step 300, a probe exchange begins when a STA sends a probe request, which contains a set of IEs that characterize the STA itself and asks the AP for some properties. The probe exchange allows the STA to scan neighboring BSSs and their capabilities. The probe response sent by the AP in step 360 provides basic properties of the BSS driven by the AP.

[0104] In step 350, the AP receives a probe request from a non-AP station. In step 360, the AP sends a probe response to the non-AP station. In step 310, the non-AP station receives a probe response from the AP. These exchanges are called probe exchanges. Probe exchanges allow STAs to scan neighboring BSSs and their capabilities. These capabilities may include capabilities related to privacy management. The probe response sent by the AP in step 360 provides basic properties of the BSS driven by the AP. It may include the PE parameter policy of the BSS.

[0105] Authentication exchanges are exchanges where the STA and AP exchange their identities at a mutually acceptable level. These exchanges include sending an authentication request in step 320. In step 370, the authentication request is received by the AP. In step 380, the AP sends an authentication response. In step 330, the authentication is received by the non-AP station. During this phase during steps 320, 330, 370, 380, some parameters such as encryption keys may be exchanged. In some embodiments, information elements related to privacy management may be included in the frames exchanged during authentication.

[0106] The association exchange is the last stage of the association process, during which the AP verifies or does not verify the membership of the STA in the BSS. The association begins with the STA sending an association request to the AP in step 340. In step 390, the association request is received by the AP. In step 391, the AP sends an association response to the non-AP station. In step 341, the association response is received by the non-AP station. The AP responds with an association response 341, 391. If the station is allowed, the association response is provided with the association status error code set to a zero value to indicate that the association is successful. If the station is not allowed, the association response is provided with the association status error code set to a non-zero value. The association status error code may indicate the reason why the AP does not allow the non-AP station. In an embodiment, as indicated in steps 340, 341, 390, 391, the association request frame and the association response frame contain a set of IEs that characterize the PE parameters of the STA itself and request the PE parameters and / or some attributes of the AP. Therefore, the association status error code may be related to privacy management. The capability exchange is completed at this stage, and the AP informs the STA of specific parameters within the BSS. In some embodiments, information elements related to privacy management may be included in the frames exchanged during association.

[0107] The Probe Request / Response frame, Authentication Request / Response frame, and Association Request / Response frame are management frames. Therefore, they can contain different information elements, including information elements related to privacy management. Therefore, they can be exchanged between the STA and the AP during the association process. Figure 2a , Figure 2b and Figure 2c Any kind of privacy IE as described in . Figure 3a and Figure 3b In one embodiment shown, the privacy information element is exchanged during the association exchange. A STA may transmit an association request with a privacy information element of the STA, which characterizes the status of the PE parameters supported by the STA (which means "the PE parameters can be manipulated or obfuscated").

[0108] like Figure 2cAs described, the status of the PE parameter is divided into two parts: the capability field 240 means that the STA is able to support the obfuscation of the corresponding PE parameter, and the enable field 241 means that the STA requests to enable the obfuscation of the corresponding PE parameter. The privacy information element of the association request frame may contain some privacy fields with the capability field set to 1 and the enable field set to 0, and some other privacy fields with the capability field set to 1 and the enable field set to 1. In the case where the STA sends a privacy information element containing a privacy field with the capability field set to 1 and the enable field set to 0, this means that the STA notifies the AP that the STA supports the corresponding PE parameter but does not require the PE parameter to be enabled during transmission. In the case where the STA sends a privacy information element containing a privacy field with the capability field set to 1 and the enable field set to 1, this means that the STA requires the AP to obfuscate the corresponding PE parameter. In the case where the capability field is set to 0, this means that the station cannot cope with the obfuscation of the parameter. It is worth noting that the situation where the capability field is set to 0 and the enable field is set to 1 should not occur, because if the station cannot cope with obfuscation, the station should not require obfuscation of the PE parameter.

[0109] In case all enable fields are set to 0, the message corresponds to a simple signaling of the station's privacy-related capabilities without requesting any privacy level. This signaling message alone does not require a response from other stations.

[0110] When a station signals the capabilities of the station related to supported PE parameters, typically all supported PE parameters are signaled. In some embodiments, it may occur that a station signals only a portion of the capabilities of the station. For example, when responding to a message signaled by a station indicating its own supported PE parameters, the AP may signal only the PE parameters supported by the AP in the set of PE parameters supported by the station.

[0111] In an embodiment, the capability field is implicit. In this case, Figure 2c The state shown includes only the Enable field. In this embodiment, the station does not advertise its full capabilities to the other party. The request to enable a PE parameter is made without the other party knowing whether the station supports it. In the event that the other party does not support the PE parameter for which obfuscation is requested, it may send a response (or any other type of signaling) with the Enable field set to 0 for that parameter. This response corresponds to a rejection of obfuscation of the PE parameter.

[0112] According to an embodiment, in the event of confusion of PE parameters requested by one party rejecting the other party, this may cause the station to abandon the association process, or to disassociate itself from the BSS if the station is already associated. In some cases, this may also cause the AP to reject the association, or to disassociate the station if the station is already associated.

[0113] The AP sends an Association Response frame in response, which may include a Privacy IE for specifying the PE parameters to be applied by the STA, which are supported and either enabled or not enabled. The list of PE parameters that the STA requires to be enabled may be different from the list of PE parameters transmitted by the AP inside the Association Response frame. Some PE parameters that are only signaled as supported by the STA may be enabled by the AP later when the AP will require, for example, an increase in the privacy level.

[0114] If the privacy alignment field 210 is set to 1 in the information element sent by the AP, it means that the BSS is subject to a unified privacy policy that applies the provided PE parameters to all other associated STAs. In other embodiments, this means that the provided PE parameters are applied to a predefined STA group. In this case, the privacy policy is uniformly applied to the STA group rather than the entire BSS.

[0115] In case the privacy alignment field 210 is set to 1 in the information element sent by the non-AP station, it means that the station requests a unified policy to be applied in the BSS, or alternatively in some embodiments, the station requests a unified policy to be applied in a station group (a group defined by the AP).

[0116] In the case where a non-AP station requires that all stations of the BSS apply a uniform privacy level, the AP broadcasts this requirement to all associated non-AP stations. In the case where some of the connected non-AP stations cannot meet the requested privacy level, the AP may decide to disassociate these non-AP stations. Alternatively, in other embodiments, the AP may decide to reject the association of non-AP stations that require this privacy level and keep the already associated stations.

[0117] Figure 3c A table showing the associated status error codes used in the embodiment of the present invention.

[0118] If the Association Status Error Code of the Association Response is set to 0 (indicating a status called SUCCESS), the privacy level of the STA is acceptable to the AP.

[0119] If the Association Status Error Code of the Association Response is set to REFUSED_REASON_LOW_PRIVACY (e.g., value 131), the association procedure fails and the STA must resend another Association Request with a Privacy IE that includes other PE parameters. In this case, the Association Response does not include any indication of the PE parameters that the AP can grant.

[0120] If the Association Status Error Code of the Association Response is set to REFUSED_WITH_SUGGESTED_HIGHER_PRIVACY (e.g., value 132), the AP includes a Privacy IE corresponding to the proposed PE parameters in the Association Response. To verify its membership in the BSS, the STA must resend another Association Request frame including a Privacy IE with the proposed PE parameters.

[0121] If the association status error code of the association response is set to REFUSED_WITH_SUGGESTED_OTHER_BSS (e.g., value 133), the AP recommends that the STA perform other association procedures in other BSSs linked to the AP. For example, in a multi-link environment, the linked BSS is announced in the multi-link information element.

[0122] Figure 4 A privacy action frame 400 is shown that can be used in exchanges between an AP and a non-AP station. The privacy action frame 400 includes:

[0123] Category field 410, which is set to a predefined value. This value may be defined as a new value for the Privacy Action Frame added in the 802.11-2020 specification, such as a value of 37;

[0124] Action field 420, which may be set to a value of 0 to indicate a request and a value of 1 to indicate a response;

[0125] Field 430, which may contain one or more privacy information elements. These information elements may be used to indicate a PE parameter set. The PE parameter set may be, for example, an updated PE parameter set requested by an upper layer of the station.

[0126] The privacy action frame is typically used in exchanges that occur between already associated non-AP stations and AP stations to change the privacy level of their communications.

[0127] Figure 5a and Figure 5b The main steps of the method for operating the method for modifying the privacy level by the non-AP STA in an embodiment of the present invention are shown. The method aims to modify the privacy level (meaning the enabled PE parameter set) between the non-AP station and the AP station. It is assumed that the non-AP station is already associated with the BSS controlled by the AP. Therefore, the initial privacy level has been used between the non-AP station and the AP station.

[0128] A change in privacy level may be requested by a non-AP station, for example, as a requirement of an application running on the non-AP station. Figure 5a and Figure 5b In some cases, for example, Figure 6 As detailed, the AP may be the station that requests the change.

[0129] In the case where the STA is associated with the BSS, the AP has verified the enabled PE parameter set during the association process. The STA is linked to the upper layer for managing user applications. For example, if a user application requires a higher privacy level, then in step 500, the STA receives a request from the upper layer to increase the privacy level. Then, the STA sends a privacy action frame to the AP, such as Figure 4 Action frame 400 is described.

[0130] Upon receiving the privacy request action frame in step 511, the AP accepts or does not accept the new PE parameter set. In step 540, the AP responds to the received request by sending a privacy response action frame. The privacy response action frame contains the PE parameter set to be applied from now on. If the AP has accepted the request, the PE parameter set in the privacy response action frame corresponds to the PE parameter set requested by the non-AP station. If the AP rejects the request, the PE parameter set in the privacy response action frame corresponds to the previous set that was used before the request and is to continue to be applied.

[0131] In step 520, it is tested whether the privacy request action frame contains a privacy IE with the privacy alignment field 210 set to 1. If the test is true, it means that the STA requests that the privacy level requested by the STA be applied to all STAs in the BSS, or alternatively to a group of STAs in the BSS in some embodiments. In this case, the AP must request a corresponding change in privacy level to all STAs in the BSS or to all STAs in the group of STAs in the BSS. This can be done by having the AP broadcast a privacy request action frame to all other associated STAs in step 530.

[0132] In other embodiments, the AP broadcasts a privacy request action frame to a group of STAs predefined by the AP. If the STA replies with a privacy response action frame rejecting the upgrade of the privacy level, the AP disassociates the STA from the BSS.

[0133] Figure 6 6 shows the main steps of the method for modifying the privacy level by the AP in an embodiment of the present invention. In step 600, a request for modifying the privacy level may be received from an upper layer on the AP side. In step 610, the AP sends a privacy request action frame including a PE parameter set. Figure 5a and Figure 5bThe method described is similar, in the case where the station accepts the request, the requested non-AP STA sends a privacy response action frame. The PE parameter set in the privacy response action frame is the new PE parameter set requested by the AP. In the case where the station refuses to change the privacy level, the previous PE parameter set to continue to be used is sent.

[0134] The change in privacy level requested by the upper layer of the AP may involve all non-AP stations of the BSS, or at least one non-AP station group in the BSS. Thus, the request to change the privacy level may be broadcast to all stations, or the request may be addressed to the station group.

[0135] In some embodiments, when the station cannot give a positive response to the request, the AP decides to disassociate the station.

[0136] Figure 3a , Figure 3b , Figure 3c , Figure 5a , Figure 5b and Figure 6 The methods described are merely examples of privacy management methods. Figure 2a , Figure 2b , Figure 2c , Figure 2d and Figure 4 The described information elements and action frames may be used to implement any privacy policy in a BSS. An AP or any non-AP station connected to an AP may require a privacy level and an associated privacy policy.

[0137] In some embodiments, the AP requires a uniform privacy level to be applied in the BSS. In this case, any non-AP station that cannot meet the required privacy level is not accepted during the association phase, or if an association has already been made, the association of the non-AP station is contacted.

[0138] In some embodiments, the AP may group non-AP stations according to any criteria. For example, the stations may be grouped according to their capabilities, which may correspond to the generation of the standard or the technology implemented in the station (e.g., high efficiency (HE), extremely high throughput (EHT), etc.). In other embodiments, the station group may consist of stations that are identified as exhibiting coherent motion. This may be the case where embedded devices such as devices held by a user (e.g., a user's phone, headphones, and a connected watch, etc.) are all connected to the same AP. The AP may also group stations identified as not moving together in a first group and stations identified as moving together in a second group.

[0139] Once the AP has created different station groups, it may require a uniform privacy level within each group. Alternatively, the AP may decide to manage virtual BSSs, one for each station group. In this case, a uniform privacy level may be applied to each virtual BSS managed by the AP.

[0140] Figure 7 A communication device 700 (typically a wireless network) configured to implement at least one embodiment of the present invention is shown. Figure 1 The communication device 700 may preferably be a device such as a microcomputer, a workstation, or a light portable device. The communication device 700 may include a communication bus 705, which may connect:

[0141] - a central processing unit 701, such as a processor, denoted as a CPU;

[0142] - a memory 703, denoted MEM, for storing executable code of a method or steps of the method according to an embodiment of the invention and registers adapted to record variables and parameters required to implement the method; and

[0143] At least two communication interfaces 702 and 702', connected to a wireless communication network (for example a communication network conforming to one of the IEEE 802.11 series of standards) via a transmitting antenna 704 and a receiving antenna 704', respectively.

[0144] Preferably, the communication bus 705 can provide communication and interoperability between various elements included in or connected to the communication device 700. The form of the bus is not limited, and in particular, the central processing unit can be operated to communicate instructions to any element of the communication device 700 directly or with the help of other elements of the communication device 700.

[0145] The executable code may be stored in a read-only memory, a hard disk, or may be stored on a removable digital medium such as a disk, etc. According to an optional variant, the executable code of the program may be received via the interface 702 or 702' by means of a communication network to be stored in the memory 703 of the communication device 700 before executing the executable code.

[0146] In an embodiment, the apparatus 700 may be a programmable device that implements embodiments of the invention using software. However, alternatively, embodiments of the invention may be implemented in whole or in part in hardware, for example in the form of an application specific integrated circuit (ASIC).

[0147] Any step of the algorithm of the present invention may be implemented in software by a programmable computing machine (such as a PC ("personal computer"), a DSP ("digital signal processor") or a microcontroller, etc.) executing a set of instructions or a program, or may be implemented in hardware by a machine or a dedicated component (such as an FPGA ("field programmable gate array") or an ASIC ("application-specific integrated circuit"), etc.).

[0148] Although the present invention has been described above with reference to specific embodiments, the present invention is not limited to these specific embodiments, and modifications within the scope of the present invention will be apparent to those skilled in the art.

[0149] Those skilled in the art will appreciate many further modifications and variations with reference to the embodiments illustrated above, which are given by way of example only and are not intended to limit the scope of the invention, which is determined solely by the appended claims. In particular, different features from different embodiments may be interchangeable where appropriate.

[0150] The above-mentioned embodiments of the present invention may be implemented separately or as a combination of multiple embodiments. In addition, when necessary or when it is beneficial to combine elements or features from various embodiments in a single embodiment, features from different embodiments may be combined.

[0151] In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. The mere fact that different features are recited in mutually different dependent claims does not mean that a combination of these features cannot be used to advantage.

Claims

1. A method for managing privacy levels in a wireless network, the wireless network comprising an access point station (AP station) and at least one non-AP station, the method comprising: Using the first station as a non-AP station or AP station, sending a message including information indicating a privacy enhancement parameter set (PE parameter set) to be obfuscated to a second station, the PE parameter set corresponding to the privacy level requested by the first station; and A response is received from the second station indicating whether the second station accepts the requested privacy level.

2. The method according to claim 1, wherein: The message also includes an indication of PE parameters supported by the first station.

3. The method according to claim 1, wherein: The information indicating the PE parameter set is an information element including, for each possible PE parameter, an indication of whether the PE parameter belongs to a PE parameter set corresponding to the requested privacy level.

4. The method according to claim 1, wherein: The information for indicating the PE parameter set is an information element including, for at least one privacy profile, whether the privacy profile corresponds to a requested privacy level, wherein the privacy profile corresponds to the PE parameter set.

5. The method according to claim 1, wherein: The message also includes a privacy alignment indication for indicating whether the requested privacy level must be applied to stations belonging to a group of stations connected to the AP station.

6. The method according to claim 5, wherein: The group of stations connected to the AP station includes all stations connected to the AP station.

7. The method according to any one of claims 1 to 6, wherein: The first station is a non-AP station, the message is a management frame sent during association of the non-AP station, and the method further comprises: In the event that the AP does not accept the requested privacy level, a message is received from the AP station indicating a rejection of association.

8. The method according to claim 5, wherein: The first station is a non-AP station; The privacy alignment indication is used to indicate that the requested privacy level must be applied to the station group; as well as The method further comprises: utilizing the AP station, A message requesting the requested privacy level is broadcast to all stations in the station group.

9. The method according to claim 7, wherein: The method further comprises: utilizing the AP station, In case at least one station in the group of stations cannot meet the requested privacy level, association of the first station is denied.

10. The method according to claim 7, wherein: The method further comprises: utilizing the AP station, disassociating stations in the station group that fail to meet the requested privacy level; and Accept the association of the first station.

11. The method according to any one of claims 1 to 5, wherein: The first station is the AP station; and The message is an action frame.

12. The method according to claim 10, wherein: The method further comprises: In the event that the second station cannot meet the requested privacy level, the second station is disassociated.

13. A method for managing privacy levels in a wireless network, the wireless network comprising an access point station (AP station) and at least one non-AP station, the method comprising: Using a station as a non-AP station or an AP station, A message including information indicating a privacy enhanced parameter set (PE parameter set) supported by the station is sent to other stations.

14. A computer program product for a programmable device, the computer program product comprising a sequence of instructions for implementing the method according to any one of claims 1 to 13 when the sequence of instructions is loaded into and executed by the programmable device.

15. A computer-readable storage medium storing computer program instructions for implementing the method according to any one of claims 1 to 13.

16. A computer program which, when executed, causes the method of any one of claims 1 to 13 to be performed.

17. A first station device for managing a privacy level in communication with a second station in a wireless network, the wireless network comprising access point stations (AP stations) and non-AP stations, the first station device being the non-AP station or the AP station, the first station device comprising a processor, the processor being configured to: sending a message including information indicating a privacy enhancement parameter set (PE parameter set) to be obfuscated to the second station, the PE parameter set corresponding to the privacy level requested by the first station; and A response is received from the second station indicating whether the second station accepts the requested privacy level.

18. A station device for managing a privacy level in a wireless network, the wireless network comprising an access point station (AP station) and at least one non-AP station, the station device being a non-AP station or an AP station, the station device comprising a processor, the processor being configured to: A message including information indicating a privacy enhanced parameter set (PE parameter set) supported by the station is sent to other stations.

19. A privacy information element capable of being inserted into a message for managing a privacy level in a wireless network comprising an access point station (AP station) and at least one non-AP station, in, The privacy information element includes information for indicating the privacy enhanced parameter set (PE parameter set) supported by the station and / or to be obfuscated.

20. The private information element of claim 19, wherein: The privacy information element includes the following status for each PE parameter, and the status includes: A capability field, used to indicate whether the PE parameter is supported; and The Enable field is used to indicate whether to obfuscate the PE parameters.

21. The private information element of claim 19, wherein: The private information element includes an identifier of a configuration file, the configuration file corresponds to a PE parameter set, and the private information element includes the following status for the configuration file, the status including: A capability field, used to indicate whether the PE parameter is supported; and The Enable field is used to indicate whether to obfuscate the PE parameters.

22. A privacy information element capable of being inserted into a message for managing a privacy level in a wireless network comprising an access point station (AP station) and at least one non-AP station, in, The privacy information element includes a privacy enhancement parameter set (PE parameter set) and a profile identifier for defining a profile corresponding to the PE parameter set.

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