Communication apparatus and method for enhanced tunneled direct link setup (TDLS)

Abstract

In one exemplary embodiment, a communication apparatus and method for enhanced Tunneled Direct Link Setup (TDLS) is provided, comprising: a first wireless communication device associated with a first access point (AP), the first wireless communication device including: a transmitter configured, in operation, to transmit a request frame for peer-to-peer communication to a second wireless communication device associated with a second AP; and a receiver configured, in operation, to receive a response frame from the second wireless communication device in response to the request frame.

Description

[Technical Field]

[0001] The present disclosure relates generally to communication methods and apparatus, and more particularly to methods and apparatus for enhanced Tunneled Direct Link Setup (TDLS). [Background technology]

[0002] Tunnelled Direct Link Setup (TDLS) enables peer-to-peer communication between two non-access point (non-AP) stations (STAs) in an 802.11 BSS. All management frames involved in TDLS setup (except TDLS discovery responses) are encapsulated within data frames, making TDLS setup completely transparent to the AP associated with the non-AP STA. In fact, the AP does not even need to support TDLS.

[0003] However, there is still limited discussion about communication devices and methods for enhanced TDLS.

[0004] Therefore, there is a need for a communications apparatus and method that can solve the above problems. Furthermore, other desirable features and characteristics will become apparent from the following detailed description and the appended claims, taken in conjunction with the accompanying drawings and this background of disclosure. Summary of the Invention

[0005] The non-limiting exemplary embodiments contribute to providing a communication apparatus and method for enhanced TDLS.

[0006] According to one aspect of the present disclosure, there is provided a first wireless communication device associated with a first access point (AP), the first wireless communication device including: a transmitter configured, in operation, to transmit a request frame for peer-to-peer communication to a second wireless communication device associated with a second AP, and a receiver configured, in operation, to receive a response frame from the second wireless communication device in response to the request frame.

[0007] According to another aspect of the present disclosure, there is provided a second wireless communication device associated with a second AP, the second wireless communication device including: a receiver configured, in operation, to receive a request frame from a first wireless communication device via a first AP associated with the first wireless device and the second AP, the request frame indicating a request for peer-to-peer communication with the second wireless communication device; and a transmitter configured, in operation, to transmit a response frame to the first wireless communication device in response to the request frame.

[0008] According to another aspect of the present disclosure, there is provided a communication method, including: transmitting a request frame from a first wireless communication device to a second wireless communication device via a first AP associated with the first wireless communication device and a second AP associated with the second wireless communication device, the request frame indicating a request for peer-to-peer communication with the second wireless communication device; and receiving a response frame from the second wireless communication device in response to the request frame.

[0009] It should be noted that the general or specific embodiments can be implemented as a system, a method, an integrated circuit, a computer program, a storage medium, or any selective combination thereof. Further advantages and effects of an embodiment of the present disclosure will be apparent from the specification and drawings. Such advantages and / or effects are provided by some embodiments and features described in the specification and drawings, but not all of them are necessarily provided to obtain one or more identical features. [Brief explanation of the drawings]

[0010] In the accompanying drawings, where like reference numerals refer to identical or functionally similar elements throughout several separate views, and which, together with the detailed description set forth below, are incorporated into or constitute a part of this specification, serve to further illustrate various embodiments and explain all of the various principles and advantages of the present invention. [Figure 1] Diagram showing an example Tunnelled Direct Link Setup (TDLS) scenario [Figure 2A] Diagram showing an example of the TDLS discovery process using the TDLS Discovery frame [Figure 2B] Diagram showing an example of the TDLS discovery process using Access Network Query Protocol (ANQP) frames [Figure 3] Diagram showing an example of an Extended Service Set (ESS) network [Figure 4] Diagram showing an example of a Basic Service Set (BSS) network [Figure 5] Diagram showing an example of an Overlapping Basic Service Set (OBSS) network [Figure 6] FIG. 1 illustrates an enhanced TDLS setup procedure in accordance with various embodiments of the present disclosure. [Figure 7A] FIG. 1 illustrates a TDLS Discovery Request frame format according to an embodiment of the present disclosure. [Figure 7B] FIG. 1 illustrates a TDLS Discovery Response frame format according to an embodiment of the present disclosure. [Figure 8] 1 is a flow diagram of TDLS Discovery frame exchange signaling for AP-to-AP wired backhaul according to one embodiment of the present disclosure; [Figure 9A]1 is a flow diagram of TDLS Discovery frame exchange signaling for AP-to-AP wireless backhaul according to one embodiment of the present disclosure; [Figure 9B] 1 is a flow diagram of TDLS Discovery frame exchange signaling for AP-to-AP wireless backhaul according to one embodiment of the present disclosure; [Figure 10] FIG. 1 illustrates a four-address data frame format for inter-AP communication, according to one embodiment of the present disclosure. [Figure 11] FIG. 1 illustrates an enhanced TDLS discovery procedure in which the Link Identifier element of the TDLS Discovery frame indicates the BSS Identifier (BSSID) of the BSS associated with the TDLS initiator, according to one embodiment of the present disclosure. [Figure 12] FIG. 1 illustrates an enhanced TDLS discovery procedure in which the Link Identifier element of a TDLS Discovery frame indicates the BSSID of the BSS associated with a TDLS peer STA, according to one embodiment of the present disclosure. [Figure 13] FIG. 1 illustrates an enhanced TDLS discovery procedure in which the Link Identifier element of the TDLS Discovery frame indicates the BSSIDs of the BSS associated with the TDLS initiator and the BSS associated with the TDLS peer STA, according to one embodiment of the present disclosure. [Figure 14A] FIG. 12 illustrates the Link Identifier element used in the example of FIG. 11 , according to one embodiment of the present disclosure. [Figure 14B] FIG. 13 illustrates the Link Identifier element used in the example of FIG. 12, according to one embodiment of the present disclosure. [Figure 14C] FIG. 14 illustrates the Link Identifier element used in the example of FIG. 13, according to one embodiment of the present disclosure. [Figure 15] FIG. 1 illustrates the overall signaling details of an enhanced TDLS discovery procedure according to one embodiment of the present disclosure. [Figure 16]FIG. 1 illustrates a security negotiation procedure for a TDLS link according to one embodiment of the present disclosure. [Figure 17] FIG. 1 illustrates a Fast BSS Transition (FTE) element for deriving a TDLS PeerKey (TDK) in a TDLS link security negotiation procedure, according to one embodiment of the present disclosure. [Figure 18] FIG. 10 illustrates a modified example of a TDLS Discovery Response frame format according to an embodiment of the present disclosure. [Figure 19] FIG. 1 illustrates a TDLS implementation with multiple BSSIDs, according to one embodiment of the present disclosure. [Figure 20] FIG. 1 is a block diagram illustrating a STA suitable for communication according to various embodiments of the present disclosure. [Figure 21] 1 is a flow diagram illustrating an enhanced TDLS method according to various embodiments of the present disclosure. [Figure 22] 1 is a schematic partial schematic diagram of a STA that can be implemented for enhanced TDLS in accordance with various embodiments of the present disclosure.

[0011] Those skilled in the art will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. DETAILED DESCRIPTION OF THE INVENTION

[0012] The following detailed description is merely exemplary in nature and is not intended to limit the embodiments or their application and uses. There is no intention to be bound by the preceding background or theories presented in this detailed description. Furthermore, other desirable features and characteristics will become apparent from the following detailed description and the appended claims, taken in conjunction with the accompanying drawings and this background of the disclosure.

[0013] Some embodiments of the present disclosure will now be described, by way of example only, with reference to the following drawings in which like reference numbers and letters indicate similar or equivalent elements:

[0014] In the following paragraphs, a particular exemplary embodiment is described with reference to an access point (AP) and a station (STA) for enhanced TDLS.

[0015] In the context of IEEE 802.11 (Wi-Fi) technology, a station, also interchangeably referred to as a STA, is a communication device capable of using the 802.11 protocol. Based on the definition in IEEE 802.11-2016, a STA can be any device that includes a media access control (MAC) and physical layer (PHY) interface to the wireless medium (WM) compliant with IEEE 802.11. For example, a station can be a laptop, desktop personal computer (PC), personal digital assistant (PDA), access point or non-access point (e.g., AP STA or non-AP STA), or Wi-Fi phone in a wireless local area network (WLAN) environment. A station can be fixed or mobile. In a WLAN environment, the terms "STA," "non-AP STA," "wireless client," "user," "user device," and "node" are often used interchangeably.

[0016] Similarly, an AP, also interchangeably called a Wireless Access Point (WAP) in the context of IEEE 802.11 (Wi-Fi) technology, is a communications device that allows STAs in a WLAN to connect to a wired network. APs are typically connected to a router (through the wired network) as standalone devices, but can also be integrated into or used within a router.

[0017] As mentioned above, a STA in a WLAN may function as an AP at other times, and vice versa. This is because a communication device in the context of IEEE 802.11 (Wi-Fi) technology may include both STA and AP hardware components. In this manner, the communication device can switch between STA mode and AP mode based on the conditions and / or requirements of the actual WLAN.

[0018] 1 illustrates an example 100 of a Tunneled Direct Link Setup (TDLS) between STA 102 and STA 104 associated with AP 106. In this example, STA 102 initiates the TDLS setup and is therefore referred to as the TDLS initiator, and STA 104 is referred to as the TDLS responder or peer STA. The setup generally involves STA 102 sending a TDLS discovery or setup request to STA 104 via AP 106, after which STA 104 sends a TDLS discovery or setup response to STA 102 via AP 106. After the TDLS setup is successfully completed, STA 102 and STA 104 can communicate directly without going through AP 106.

[0019] TDLS discovery is performed using a TDLS Discovery frame, as shown in example 200 of FIG. 2A . TDLS initiator STA 202 sends a TDLS Discovery Request frame to STA 204 via AP 206. If STA 204 supports TDLS, it sends a TDLS Discovery Response frame directly to STA 202 (e.g., via a direct link or path without going through AP 206). TDLS discovery can also be performed by exchanging Access Network Query Protocol (ANQP) Request / Response frames (e.g., Group Address GAS Request / Response frames) via a direct path, as shown in example 208 of FIG. 2B . For example, STA 210 sends an ANQP Request frame directly to STA 212 (e.g., via a direct link or path without going through AP 214). If STA 212 supports TDLS, it sends an ANQP response directly to STA 210.

[0020] In home and enterprise scenarios, there may be multiple APs in close proximity, making a large number of STAs available, forming an Overlapping Basic Service Set (OBSS). In an OBSS scenario, there may be multiple clients in close proximity to each other. Future improvements in mainstream WiFi may take advantage of this to enable peer-to-peer communication with clients in the OBSS.

[0021] Furthermore, in current home and enterprise scenarios, a network may consist of multiple APs forming an Extended Service Set (ESS). An ESS refers to a collection of one or more basic service sets (BSSs) interconnected by a single distribution system (DS). An ESS appears to the Logical Link Control (LLC) sublayer as a single IEEE 802 access domain. Figure 3 shows an example ESS network 300, in which APs 302, 304, and 306 (with BSSs 310, 312, and 314, respectively) are interconnected by a DS 308. To improve throughput, 802.11 also specifies co-located APs, where, for example, the same physical device may include two APs operating on different channels.

[0022] In the current IEEE specification, Tunneled Direct Link Setup (TDLS) is a procedure characterized by "encapsulating a setup frame in a data frame so that the setup frame can be transmitted through an AP." For example, referring to example 400 in FIG. 4, STA 402 is wirelessly connected to AP 406, and STA 404 is wirelessly connected to AP 408. APs 406 and 408 are connected via a backhaul link and form part of an ESS. By performing a TDLS setup, STA 402 and STA 404 can communicate directly over the direct link without passing through AP 406 and AP 408.

[0023] In the current 802.11 specification, the TDLS mechanism is only for peer-to-peer communication within the same BSS. This disclosure proposes a solution that enables the TDLS mechanism to establish peer-to-peer (P2P) links with clients in an OBSS scenario, where STA 502 (associated with AP 506 in the BSS) can communicate directly with STA 504 (associated with AP 508 in the OBSS), as shown in example 500 in Figure 5.

[0024] The solution for a TDLS initiator to establish a TDLS setup with a TDLS responder in an OBSS is as follows: The TDLS initiator performs discovery of clients in the OBSS by forwarding a TDLS Discovery frame from its AP to the OBSS AP. If an OBSS STA (e.g., a TDLS responder) is within the radio range of the TDLS initiator, a TDLS Discovery Response is received by the TDLS initiator on the direct link. The TDLS initiator performs TDLS link setup by forwarding a TDLS Setup Request from its AP to the OBSS AP. For security purposes, a TDLS PeerKey (TPK) security key may be generated for both peer STAs that incorporates the Link Identifier element taking the OBSS AP into account.

[0025] FIG. 6 illustrates an example 600 of an enhanced TDLS setup procedure according to various embodiments of the present disclosure. A TDLS initiator STA 602 encapsulates a TDLS Discovery Request frame 610 to be transparent to the AP and transmits it to a peer STA 604 in the OBSS via an AP 606 (e.g., associated with STA 602) and an AP 608 (e.g., associated with STA 604). For example, the TDLS Discovery Request frame 610 is forwarded from the AP 606 to the AP 608. A TDLS Discovery Response frame 612 (from STA 604 to STA 602) is received on the direct link between STA 604 and STA 602. This confirms that the STAs are within radio range of each other and can initiate TDLS setup. In this way, the OBSS STA 604 is identified during the discovery phase. Upon receiving the TDLS Discovery Response frame 612, the TDLS initiator STA 602 may establish a TDLS link with the peer STA 604. TDLS-related parameters are then exchanged during the exchange of a TDLS Setup Request frame 614 and a TDLS Setup Request Response frame 616. To establish a secure direct link for data communication, security-related negotiations for the direct link may be performed during the TDLS setup. A TPK key may be generated based on the BSS Identifiers (BSSIDs) of both BSSs (the BSS associated with STA 602 and AP 606 and the BSS associated with STA 604 and AP 608) or information contained in a Link Identifier element with either of these BSSIDs.

[0026] Enhanced TDLS (eTDLS) features encapsulation of setup frames into data frames, allowing them to be transmitted transparently through one or more APs. Therefore, each AP does not need to be direct link capable or similarly support the capabilities used in a TDLS link between two TDLS peer STAs. eTDLS also provides power-saving modes in the form of TDLS peer PSM (scheduled) and TPU (unscheduled). STAs that have set up an eTDLS direct link remain associated with their respective BSSs but have the option to transmit frames directly over the direct link. Class 3 data frames may be used for data frames transmitted between STAs within an infrastructure BSS or MBSS and between TDLS peer STAs in different BSSs. Management frames used in eTDLS follow the same rules as traditional TDLS.

[0027] During eTDLS discovery, a TDLS initiator can send a TDLS Discovery Request frame to a peer STA within an OBSS by encapsulating the TDLS Discovery Request frame in the payload of an Ethertype 89-0d data frame. Because the peer STA resides within an OBSS, the TDLS Discovery Request frame is transmitted to the peer STA via multiple APs. The TDLS Discovery Request frame is relayed from an AP within the TDLS initiator's BSS to the peer STA's AP (frame relay between APs is outside the scope of 802.11). A peer STA that receives a TDLS Discovery Request frame responds with a TDLS Discovery Response frame on its direct link to the TDLS initiator. The BSSID of the peer STA and / or the TDLS initiator's BSSID may be included in the exchanged TDLS Discovery and Setup frames to identify that the TDLS setup belongs to the peer STA between these BSSIDs. Furthermore, it is assumed that the peer STA is operating on the same channel as the TDLS initiator.

[0028] FIG. 7A illustrates a TDLS Discovery Request frame format 700 in which a TDLS Discovery Request frame 706 is encapsulated in an Ethertype 89-0d data frame according to one embodiment of the present disclosure. The Payload Type field 702 is set to enhanced TDLS, indicating that the data frame is for enhanced TDLS. Alternatively, the Payload Type field may be set to TDLS, the same as traditional TDLS. In that case, some signaling is included in the Payload field 704 to indicate eTDLS capabilities or preferences, as described below. These Payload Type field options may also be applied to other TDLS frames. The Payload field 704 includes a TDLS Discovery Request frame 706 with a Category field 708 set to TDLS, a TDLS Action field 710 indicating that the frame 706 is for a TDLS discovery request, and a Link Identifier element 712. The TDLS Discovery Request frame format 700 may be used as the encapsulated TDLS Discovery Request frame 610 of FIG. 6. When an Aggregated Media Access Control (MAC) service data unit (A-MSDU) is used to encapsulate the TDLS Discovery Request frame 706, the source and destination addresses are carried in the sub-frame header instead of the address field, in which case the destination address (DA) and source address (SA) are included in the sub-frame header.

[0029] 7B illustrates a TDLS Discovery Response frame format 714 according to one embodiment of the present disclosure. For the TDLS Discovery Response frame format 714, a Public Action frame is used. A Public Action field 716 indicates that the frame is for an enhanced TDLS discovery response. The TDLS Discovery Response frame 714 also includes a Link Identifier element 718.

[0030] 8 shows a flow diagram 800 of TDLS discovery frame exchange signaling for AP-to-AP wired backhaul according to one embodiment of the present disclosure. The process begins with a TDLS initiator STA 802 sending a TDLS discovery request 810 to an associated AP 806 under BSS1. The TDLS discovery request 810 may have a format similar to the TDLS discovery request frame format 700, with the Address 1 field indicating the BSSID of the AP 806 as the receiving address (RA), the Address 2 field indicating the address of the STA 802 as the transmitting address (TA), the Address 3 field indicating the address of the STA 804 (e.g., the TDLS responder) as the destination address (DA), and the Payload Type field indicating Enhanced TDLS. The TDLS discovery request 810 is relayed from the AP 806 to the AP 808 under BSS2 (e.g., OBSS) via a wired backhaul (e.g., the AP 806 and the AP 808 are connected via a wired backhaul), and then forwarded from the AP 808 to the STA 804. If Ethernet (or other wired backhaul) is used between the AP 806 and the AP 808, the AP 806 and the AP 808 are included in the same L2 broadcast segment, and therefore no RA and TA are required. The TDLS discovery request 810 received by the STA 804 from the AP 808 differs in that the Address 1 field indicates the address of the STA 804 as the RA, the Address 2 field indicates the BSSID of the AP 808 as the TA, and the Address 3 field indicates the address of the STA 802 as the SA. The Payload Type field remains unchanged. In response, the STA 804 sends a TDLS discovery response 812 to the STA 802 over the direct link.The TDLS discovery response 812 may have a format similar to the TDLS Discovery Response frame format 714, where the Address 1 field indicates the address of the STA 802 as the RA, the Address 2 field indicates the address of the STA 804 as the TA, the Address 3 field indicates the BSSID of the AP 806, and the payload type field indicates Enhanced TDLS. Other options for the Address 3 field of the TDLS discovery response 812 may include indicating the BSSID to which the TDLS responder (e.g., STA 804) belongs, or a unique ID assigned to the TDLS discovery request by the TDLS initiator (e.g., STA 802). Before attempting TDLS discovery, the STA 802 may know in some way that the STA 804 is a peer STA for the intended service. A typical example is through upper layer or application-level service discovery such as UPnP or Bonjour. After learning the IP address of the peer STA through service discovery, STA 802 can determine the MAC address of STA 804 through Address Resolution Protocol (ARP), but STA 802 may not know anything about (or even the existence of) AP2 and BSS2 during this process.

[0031] 9A and 9B show a flow diagram 900 of TDLS discovery frame exchange signaling for AP-to-AP wireless backhaul according to one embodiment of the present disclosure. The process begins with a TDLS initiator STA 902 sending a TDLS discovery request 910 to an associated AP 906 under BSS1. The TDLS discovery request 910 may have a format similar to the TDLS discovery request frame format 700, where the Address 1 field indicates the BSSID of the AP 906 as the RA, the Address 2 field indicates the address of the STA 902 as the TA, the Address 3 field indicates the address of the STA 904 (e.g., the TDLS responder) as the DA, and the Payload Type field indicates Enhanced TDLS. The TDLS discovery request 910 is then forwarded from the AP 906 to the AP 908 under BSS2 (e.g., BSS) via the wireless backhaul (e.g., the AP 906 and the AP 908 are connected via the wireless backhaul). Here, the TDLS discovery request 910 that the AP 908 receives from the AP 906 has different settings, with the Address 1 field indicating the BSSID of the AP 908 as the RA and the Address 2 field indicating the BSSID of the AP 906 as the TA. The Address 3 field and the Payload Type field remain unchanged.

[0032] The TDLS discovery request 910 received by the AP 908 is forwarded from the AP 908 to the STA 904. The TDLS discovery request 910 received by the STA 904 from the AP 908 has further different settings, with the Address 1 field indicating the address of the STA 904 as the RA, the Address 2 field indicating the BSSID of the AP 908 as the TA, and the Address 3 field indicating the address of the STA 902 as the SA. In response, the STA 904 transmits a TDLS discovery response 912 to the STA 902 via the direct link. The TDLS discovery response 912 may have a format similar to the TDLS discovery response frame format 714, with the Address 1 field indicating the address of the STA 902 as the RA, the Address 2 field indicating the address of the STA 904 as the TA, the Address 3 field indicating the BSSID of the AP 906, and the Payload Type field indicating Enhanced TDLS.

[0033] When wireless backhaul (e.g., connecting AP 906 and AP 908) is used, AP 906 may use a three-address format and set the Address 1 field to the MAC address of AP 908 as RA, the Address 2 field to its own MAC address as TA, and the Address 3 field to the MAC address of STA 904 as DA. However, the TDLS responder STA 904 needs to know the MAC address of the TDLS initiator STA 902, which is missing from the MAC header, as the SA. In this case, the TDLS initiator STA 902 may include the MAC address of STA 902 (as SA) in the payload by adding an SA field in addition to the TDLS Discovery Request Action field or by modifying the TDLS Discovery Request Action field format for eTDLS to include the SA field. Alternatively, AP 906 may use the three-address format (RA / TA / DA) to disguise the TA as the MAC address of STA 902. The AP 908 treats the frame as a frame from the DS. For example, the AP 908 sets the SA to the MAC address of the STA 902 (the TA of the received frame) and forwards the frame. Special security processing may be performed for the link, for example, using a unique security method. In another implementation, the contents of the TDLS discovery request 910 may be encapsulated in a forwarded frame indicating the SA (e.g., the MAC address of the STA 902), and the forwarded frame may be sent to the AP 908. The AP 908 interprets the forwarded frame and forwards its contents to the STA 904 in a data frame. The SA of the data frame forwarded to the STA 904 is set to the MAC address of the STA 902 using the information embedded in the forwarded frame. From an 802.11 perspective, the implementation of these AP-to-AP links is out of scope and implementation-specific. In yet another implementation, a 4-address format may be used to include RA / TA / DA / SA. These options for the AP-to-AP link may also apply to other TDLS frames forwarded by the AP.

[0034] 10 illustrates a four-address data frame format 1000 for AP-to-AP communication, according to an embodiment of the present disclosure. Based on the example 900 as an example, the addressing in the frame format 1000 is as follows for communication between APs (e.g., between AP 906 and AP 908): The From DS field and the To DS field (not shown) are both set to 1. The Address 1 field 1002 is set to the BSSID of BSS2 (e.g., the BSS associated with AP 908) as the RA. The Address 2 field 1004 is set to the BSSID of BSS1 (e.g., the BSS associated with AP 906) as the TA. The Address 3 field 1006 is set to the address of STA 904 as the DA. The Address 4 field 1008 is set to the address of STA 902 as the SA. Furthermore, the Payload Type field 1010 is set to TDLS.

[0035] 11 illustrates an example 1100 of an enhanced TDLS discovery procedure in which a Link Identifier element in a TDLS Discovery frame indicates the BSS Identifier (BSSID) of a BSS associated with a TDLS initiator, according to one embodiment of the present disclosure. An STA 1102 initiates the TDLS procedure (e.g., a TDLS initiator) similarly to a conventional TDLS procedure, except that an enhanced TDLS flag (indicating the STA's 1102's enhanced TDLS capabilities or preferences) is included in the TDLS Discovery Request frame 1110. The flag may be carried in a capabilities element (e.g., an Extended Capabilities element) or a newly defined Extended TDLS element. In a TDLS Discovery Request frame 1110 sent from the STA 1102 to its associated AP 1106, the Address 1 field is set to the address of the AP 1106 as the RA, the Address 2 field is set to the address of the STA 1102 as the TA, the Address 3 field is set to the address of the STA 1104 (e.g., the TDLS responder) as the DA, and the Link Identifier element indicates BSSID1 (e.g., an identifier of the BSS associated with the AP 1106, or the MAC address of the AP 1106). The TDLS Discovery Request frame 1110 is forwarded by the AP 1106 to the AP 1108 (e.g., the AP associated with the TDLS responder STA 1104). The inter-AP path between the AP 1106 and the AP 1108 may be a wired or wireless backhaul, a wireless relay, or other similar path.

[0036] After receiving the TDLS Discovery Request frame 1110, the AP 1108 transmits the frame to the STA 1104. The TDLS Discovery Request frame 1110 received by the STA 1104 now has different settings: the Address 1 field is set to the address of the STA 1104 as the RA (e.g., the frame 1110 is received by the STA 1104), the Address 2 field is set to the address of the AP 1108 as the TA (e.g., the frame 1110 is sent from the AP 1108), the Address 3 field is set to the address of the STA 1102 as the SA (e.g., the frame 1110 is sent from the TDLS initiator STA 1102), and the Link Identifier element indicates BSSID 1. However, the STA 1104 does not know at this point whether BSS 1 is a trustworthy network (e.g., whether the inter-AP path is secure). Therefore, the STA 1104 may verify whether the BSS with BSSID1 is trustworthy by sending a Probe Request frame 1112 requesting a list of trusted AP BSSs from the AP 1108, and the requested list may be provided from the AP 1108 to the STA 1104 in a Probe Response frame 1114. An example of a trusted AP (or BSS) is the AP 1106 (or BSS1) in the ESS to which the TDLS initiator STA 1102 belongs. If the STA 1104 finds BSSID1 in the trusted AP list, the STA 1104 may send a TDLS Discovery Response frame 1116 to the STA 1102 on the direct link. The TDLS Response frame 1116 may have the Address 1 field set to the address of STA1102 as RA (e.g., frame 1116 is received by STA1102), the Address 2 field set to the address of STA1104 as TA (e.g., frame 1116 is transmitted from STA1104), the Address 3 field set to indicate BSSID1, and the Link Identifier element also set to indicate BSSID1.After receiving the Response frame 1116, the STA 1102 may approve the setup of the TDLS direct link.

[0037] In one implementation, the STA 1104 may already have information about trusted APs, for example, by receiving a beacon frame or a probe response frame from the AP 1108 that includes trusted AP information. In this case, the exchange of probe request / response frames can be omitted after receiving the TDLS discovery request frame 1110. In another implementation, the STA 1104 may learn about trusted APs from the association process by receiving the trusted AP information carried by the association response frame. In another implementation, the trusted AP information may be included in one or more elements, such as a reduced neighbor report (RNR) or a neighbor report element. In multi-AP operation, a specific element (e.g., a multi-AP element) may include the trusted AP information. For example, the trusted AP information may be included in the RNR element carried by the multi-AP element, or may be included directly in a field outside the RNR element within the multi-AP element.

[0038] 12 illustrates an example 1200 of an enhanced TDLS discovery procedure in which a Link Identifier element in a TDLS Discovery frame indicates the BSSID of a BSS associated with a TDLS peer STA according to an embodiment of the present disclosure. In this example, it is assumed that the TDLS initiator STA 1202 has already discovered STA 1204 as a potential TDLS peer STA and also somehow knows which AP and BSS STA 1204 is associated with (e.g., AP 1208 and BSS 2 in this case). For example, this can be done by utilizing a Fast Initial Link Setup (FILS) Discovery frame for peer STA discovery. However, STA 1202 does not know at this point whether BSS 2 is a trusted network (e.g., whether the inter-AP path is secure). Thus, the STA 1202 may verify whether the BSS with BSSID2 is trustworthy by sending a Probe Request frame 1210 requesting a list of trusted AP BSSs from the associated AP 1206, and the requested list may be provided from the AP 1206 to the STA 1202 in a Probe Response frame 1212. If the STA 1202 determines that a potential TDLS peer STA (STA 1204) is associated with a trusted AP / BSS (AP 1208 / BSS2, e.g., within the same ESS), the STA 1202 may perform a TDLS discovery / setup procedure in which the Address field or the BSSID field in the Link Identifier element is set to BSSID2. For example, the STA 1202 may send a TDLS Discovery Request frame 1214 to the AP 1206 to initiate TDLS with the STA 1204.The TDLS Discovery Request frame 1214 may be configured with the Address 1 field set to the address of the AP 1206 as the RA, the Address 2 field set to the address of the STA 1202 (e.g., the TDLS initiator) as the TA, the Address 3 field set to the address of the STA 1204 (e.g., the TDLS responder) as the DA, and the Link Identifier element indicating BSSID2 (e.g., an identifier of the BSS2 associated with the AP 1206, or the MAC address of the AP 1206). The TDLS Discovery Request frame 1214 is then forwarded by the AP 1206 to the AP 1208 (e.g., the AP associated with the TDLS responder STA 1204). The inter-AP path between the AP 1206 and the AP 1208 may be a wired or wireless backhaul, a wireless relay, or other similar path.

[0039] After receiving the TDLS Discovery Request frame 1214, the AP 1208 transmits the frame to the STA 1204. The TDLS Discovery Request frame 1214 received by the STA 1204 now has a different configuration: the Address 1 field is set to the address of the STA 1204 as the RA (e.g., the frame 1214 is received by the STA 1204), the Address 2 field is set to the address of the AP 1208 as the TA (e.g., the frame 1214 is transmitted from the AP 1208), the Address 3 field is set to the address of the STA 1202 as the SA (e.g., the frame 1214 is transmitted from the TDLS initiator STA 1202), and the Link Identifier element indicates BSSID2. Because the Link Identifier element contains BSSID2, e.g., the BSS associated with the STA 1204, the STA 1204 may operate in the same manner as in conventional TDLS procedures. The STA 1204 may transmit a TDLS Discovery Response frame 1216 to the STA 1202 via the direct link. The TDLS discovery response frame 1216 may have the Address 1 field set to the address of STA 1202 as the RA (e.g., frame 1216 is received by STA 1202), the Address 2 field set to the address of STA 1204 as the TA (e.g., frame 1216 is sent from STA 1204), the Address 3 field set to indicate BSSID2, and the Link Identifier element also set to indicate BSSID2. After receiving the response frame 1216, STA 1202 may approve the setup of the TDLS direct link.

[0040] 13 illustrates an example 1300 of an enhanced TDLS discovery procedure in which a Link Identifier element in a TDLS Discovery frame indicates the BSSID of the BSS associated with the TDLS initiator and the BSSID of the BSS associated with the TDLS peer STA, according to one embodiment of the present disclosure. The STA 1302 initiates the TDLS procedure (e.g., TDLS initiator) in the same manner as the conventional TDLS procedure, except that an Enhanced TDLS flag (indicating the STA's 1302's enhanced TDLS capabilities or preferences) is included in the TDLS Discovery Request frame 1310. The flag may be included in a capability element (e.g., an Extended Capabilities element) or a newly defined Extended TDLS element. In a TDLS Discovery Request frame 1310 sent from the STA 1302 to its associated AP 1306, the Address 1 field is set to the address of the AP 1306 as the RA, the Address 2 field is set to the address of the STA 1302 as the TA, the Address 3 field is set to the address of the STA 1304 (e.g., the TDLS responder) as the DA, and the Link Identifier element indicates BSSID1 (e.g., the identifier of BSS1 associated with the AP 1306, or the MAC address of the AP 1306). The TDLS Discovery Request frame 1310 is then forwarded by the AP 1306 to the AP 1308 (e.g., the AP associated with the TDLS responder STA 1304). The inter-AP path between the AP 1306 and the AP 1308 may be a wired or wireless backhaul, a wireless relay, or other similar path.

[0041] After receiving the TDLS Discovery Request frame 1310, the AP 1308 transmits the frame to the STA 1304. The TDLS Discovery Request frame 1310 received by the STA 1304 has different settings: the Address 1 field is set to the address of the STA 1304 as the RA (e.g., the frame 1310 is received by the STA 1304), the Address 2 field is set to the address of the AP 1308 as the TA (e.g., the frame 1310 is sent from the AP 1308), the Address 3 field is set to the address of the STA 1302 as the SA (e.g., the frame 1310 is sent from the TDLS initiator STA 1302), and the Link Identifier element indicates BSSID 1. However, the STA 1304 does not know at this point whether BSS 1 is a trustworthy network (e.g., whether the inter-AP path is secure). Therefore, the STA 1304 may verify whether the BSS with BSSID1 is trustworthy by sending a Probe Request frame 1312 requesting a list of trusted AP BSSs from the AP 1308, and the requested list may be provided from the AP 1308 to the STA 1304 in a Probe Request frame 1314. An example of a trusted AP (or BSS) is the AP 1306 (or BSS1) in the ESS to which the TDLS initiator STA 1302 belongs. If the STA 1304 finds BSSID1 in the trusted AP list, the STA 1304 may send a TDLS Discovery Response frame 1316 to the STA 1302 on the direct link.The TDLS Response frame 1316 may have the Address 1 field set to the address of the STA 1302 as the RA (e.g., the frame 1316 is received by the STA 1302), the Address 2 field set to the address of the STA 1304 as the TA (e.g., the frame 1316 is transmitted from the STA 1304), the Address 3 field indicating BSSID2 (e.g., the identifier of BSS2 associated with the AP 1306 or the MAC address of the AP 1306), and the Link Identifier element also set to indicate BSSID2. After receiving the Response frame 1316, the STA 1302 may approve the setup of the TDLS direct link. In implementation, if the STA 1302 receives a valid TDLS Discovery Response frame except that the BSSID field of the Link Identifier element is invalid (e.g., other address fields, such as the Dialog Token field, are valid), the STA 1302 may still recognize that BSSID2 (e.g., indicated in the Address 3 field of the TDLS Discovery Response frame 1316) is trustworthy. STA 1302 may then include BSSID1 in the BSSID field when sending frames and acknowledge BSSID2 in the BSSID field when receiving frames from STA 1304 during TDLS setup.

[0042] During TDLS setup, the STA 1302 may transmit a TDLS Setup Request frame 1318 and a TDLS Setup Confirm frame 1322 to the STA 1304 via the AP 1306 and the AP 1308. In implementation, the address field and the link identifier element of the TDLS Setup Request frame 1318 when transmitted from the STA 1302 to the AP 1306 and the TDLS Setup Confirm frame 1322 when transmitted from the AP 1308 to the STA 1304 may be set similarly to the address field and the link identifier element of the TDLS Discovery Request frame 1310 transmitted from the STA 1302 to the AP 1306 and from the AP 1308 to the STA 1304, respectively. Furthermore, the STA 1304 may transmit a TDLS Setup Response frame 1320 to the STA 1302 via the AP 1308 and the AP 1306. A TDLS Setup Response frame 1320 sent from STA 1304 to AP 1308 may have the Address 1 field set to the address of AP 1308 as RA (e.g., frame 1320 is received by AP 1308), the Address 2 field set to the address of STA 1304 as TA (e.g., frame 1320 is sent from STA 1304), the Address 3 field set to the address of STA 1302 as DA, and the Link Identifier element set to indicate BSSID2. A TDLS Setup Response frame 1320 sent from AP 1306 to STA 1302 may have the Address 1 field set to the address of STA 1302 as RA (e.g., frame 1320 is received by STA 1302), the Address 2 field set to the address of AP 1306 as TA (e.g., frame 1320 is sent from AP 1306), the Address 3 field set to the address of STA 1304 as SA, and the Link Identifier element set to indicate BSSID2.

[0043] FIG. 14A illustrates a Link Identifier element 1400 used in the diagram of FIG. 11 according to one embodiment of the present disclosure. For example, a BSSID field 1402 of the Link Identifier element 1400 (e.g., included in the TDLS Discovery Request frame 1110 and the TDLS Discovery Response 1116) may indicate the BSSID of the initiator (e.g., BSSID1 in example 1100). FIG. 14B illustrates a Link Identifier element 1404 used in FIG. 12 according to one embodiment of the present disclosure. For example, a BSSID field 1406 of the Link Identifier element 1404 (e.g., included in the TDLS Discovery Request frame 1214 and the TDLS Discovery Response frame 1216) may indicate the BSSID of the responder (e.g., BSSID2 in example 1200). Furthermore, FIG. 14C illustrates a Link Identifier element 1408 used in FIG. 13 according to one embodiment of the present disclosure. For example, the BSSID1 field 1410 and the BSSID2 field 1412 of the Link Identifier element 1408 (e.g., included in the TDLS Discovery Request frame 1314 and the TDLS Discovery Response frame 1316, and the TDLS Setup Request / Response frames 1318, 1322, and 1320) may indicate the BSSID of the initiator (e.g., BSSID1 in example 1300) and the BSSID of the responder (e.g., BSSID2 in example 1300), respectively.

[0044] 15 is an example 1500 illustrating overall signaling details of an enhanced TDLS discovery procedure according to one embodiment of the present disclosure. In this example, the address fields of a TDLS Discovery Request frame 1510, a TDLS Setup Request frame 1514, and a TDLS Setup Confirm frame 1518 transmitted from a STA 1502 (e.g., a TDLS initiator) to an AP 1506 (e.g., an AP associated with the STA 1502) and from an AP 1508 (e.g., an OBSS AP associated with a peer STA 1504) to the STA 1504 (e.g., a TDLS responder) may be set similarly to the address fields of TDLS Discovery Request frames 1110, 1214, and 1310 and TDLS Setup Request frames 1318 and 1322 transmitted from the respective TDLS initiator STAs (via the respective APs) to the respective TDLS responders. However, the Link Identifier element of the TDLS Discovery Request frame 1510, the TDLS Setup Request frame 1514, and the TDLS Setup Confirm frame 1518 may be set to indicate BSSID1 (e.g., the BSSID of BSS1 associated with AP 1506), BSSID2 (e.g., the BSSID of BSS2 associated with AP 1508), or both BSSID1 and BSSID2, depending on the desired implementation.

[0045] Similarly, the address fields of a TDLS Discovery Response frame 1512 (e.g., when transmitted from STA 1504 to AP 1508 and from AP 1506 to STA 1502) may be set similarly to the address fields of the TDLS Discovery Response frames 1116, 1216, and 1316 when transmitted from the respective TDLS responder STAs to the respective TDLS initiator STAs (via the respective APs), except that the Address 3 field and the Link Identifier element of the TDLS Discovery Response frame 1512 may be set to indicate BSSID1, BSSID2, or both BSSID1 and BSSID2, respectively, depending on the desired implementation.

[0046] Furthermore, the address field of the TDLS Setup Response frame 1516 (e.g., when sent from the STA 1504 to the AP 1508 and from the AP 1506 to the STA 1502) may be configured similarly to the address field of the TDLS Setup Response frame 1320 sent from each TDLS responder STA to each TDLS initiator STA (via each AP). However, the Link Identifier element of the TDLS Setup Response frame 1516 may be set to indicate BSSID1, BSSID2, or both BSSID1 and BSSID2, depending on the desired implementation. After the TDLS Setup Confirm frame 1518 is received by the STA 1504, TDLS direct link communication on the direct path may continue between the STA 1502 and the STA 1504 until a TDLS release is performed.

[0047] A peer STA in an OBSS may be operating on a channel different from that of the TDLS initiator. In this case, the peer STA (TDLS responder) switches its channel to the primary channel of the TDLS initiator's BSS and responds on the switched channel. The channel switch request can be signaled either during the TDLS discovery or TDLS setup phase. For example, the TDLS initiator includes its operating channel in the TDLS discovery request or TDLS setup request. The TDLS responder may respond to the TDLS initiator by performing the channel switch procedure and sending a TDLS discovery response or TDLS setup response on the TDLS initiator's operating channel. When the TDLS responder switches its operating channel, it must enter power save (PS) mode with its associated AP, so that the AP recognizes that the TDLS responder STA will not receive traffic from the AP for a while. Optionally, if desired, off-channel TDLS may be negotiated by defining an enhanced TDLS channel switching procedure that is similar to the conventional TDLS channel switching procedure, but is performed via the AP rather than the direct link.

[0048] Security negotiation may be performed for the TDLS link. As described in the next paragraph, a three-way TPK handshake protocol performed on the setup link may be used to derive a security key, e.g., a TDLS PeerKey (TPK), to provide confidentiality and authentication for frames exchanged on all direct links. To enable a secure TDLS link with an OBSS peer STA, it is assumed that the OBSS peer STA resides in the same ESS as the TDLS initiator. The main advantage is that it helps protect the entire path between the TDLS initiator and the TDLS responder, including the path between APs. Alternatively, if the link between APs is not secure, a four-way handshake may be used instead of the three-way handshake, for example, by adding the transmission of an Authentication frame encapsulated in a data frame after the TDLS Setup Confirm frame or before the TDLS Setup Request frame.

[0049] 16 illustrates a security negotiation procedure for a TDLS link according to an embodiment of the present disclosure. For example, a TDLS initiator STA 1602 sends a TDLS setup request 1610 to an OBSS peer STA 1604 (e.g., a TDLS responder) via an associated AP 1606 and an OBSS AP 1608. In the TDLS setup request 1610, the BSSID of AP1 is indicated as RA (e.g., in the Address 1 field), the address of STA 1602 is indicated as TA (e.g., in the Address 2 field), and the address of STA 1604 is indicated as DA (e.g., in the Address 3 field). The TDLS setup request 1610 may include a Fast BSS Transition (FTE) element used to derive a TPK for security negotiation, and the TDLS setup request 1610 may be referred to as a TDLS Pairwise Master Key (PMK) handshake message 1. In response to the request 1610, the STA 1604 may send a TDLS setup response 1612 (e.g., TDLS PMK handshake message 2) to the STA 1602 via the AP 1608 and the AP 1606. In the TDLS setup response 1612, the address of AP1 is indicated as RA (e.g., Address 1 field), the address of the STA 1604 is indicated as TA (e.g., Address 2 field), and the address of the STA 1602 is indicated as DA (e.g., Address 3 field). The TDLS setup response 1612 may include an FTE element. In response to the response 1612, the STA 1602 may send a TDLS setup confirmation 1614 (e.g., TDLS PMK handshake message 3) to the STA 1604 via the AP 1606 and the AP 1608. In the TDLS setup confirm 1614, the BSSID of AP 1606 is indicated as RA (e.g., Address 1 field), the address of STA 1602 is indicated as TA (e.g., Address 2 field), and the address of STA 1604 is indicated as DA (e.g., Address 3 field). The TDLS setup confirm 1614 may include an FTE element.A Link Identifier element may be included in each of frames 1610, 1612, 1614, and the BSSID indicated in each Link Identifier element, as in example 1500, is up to the desired implementation.

[0050] 17 illustrates an FTE element for deriving a TDK in a TDLS link security negotiation procedure according to one embodiment of the present disclosure. The FTE element 1700 may include a Message Integrity Code (MIC) field, an Anonce field 1704, and an Snonce field 1706. For example, the contents of the Anonce field 1704 and the Snonce field 1706 are used to generate the TPK-KEY-Input as follows: - TPK-Key-Input = Hash(min (SNonce, ANonce) || max (SNonce, ANonce)) - TPK = KDF-Hash-Length(TPK-Key-Input, “TDLS PMK”, min (MAC_I, MAC_R)|| max (MAC_I, MAC_R) || BSSID) - TPK-KCK = L(TPK, 0, 128) - TPK-TK = L(TPK, 128, Length - 128)

[0051] The Key Confirmation Key (KCK) is used to provide data origin authenticity in the TDLS Setup Response and TDLS Setup Confirm frames, and the same TPK-TK is used to provide confidentiality for all protected frames sent over the direct link, where BSSID, MAC_I, and MAC_R are the values ​​of the TDLS Initiator STA Address and TDLS responder STA Address fields of the Link Identifier element carried in the TDLS Setup frame, respectively.

[0052] The MIC value may be calculated for TPK handshake messages 2 and 3 (e.g., TDLS Setup Response 1612 and TDLS Setup Acknowledgement 1614, respectively). The values ​​of the TDLS Initiator STA Address and TDLS Responder STA Address fields of the Link Identifier element included in the TDLS Setup frame are used as the TDLS initiator STA MAC address and TDLS responder STA MAC address, respectively. The MIC is calculated based on the concatenated data in the following order: TDLS initiator STA MAC address (6 octets) TDLS responder STA MAC address (6 octets) Transaction sequence number (1 octet) set to a value of 2 or 3 Link Identifier Element RSNE Timeout Interval element ·FTE whose MIC field is set to 0

[0053] The MIC may be calculated using the TPK-KCK and AES-128-CMAC algorithms.

[0054] The rules for calculating Additional Authenticated Data (AAD) and Nonce during Counter Mode with Cipher Block Chaining Message Authentication Code Protocol (CCMP) or Galois / Counter Mode Protocol (GCMP) for data frames exchanged between two non-APs over a direct link are as follows: The MAC address of the receiver is used as the Address 1 field for AAD construction. The MAC address of the sending AP is used as the Address 2 field for AAD and Nonce construction. If a non-AP STA is associated with an AP, the MAC address of the OBSS AP is used as the Address 3 field for AAD construction. Otherwise, the Address 3 field of the protected frame is used for AAD construction. Alternatively, the addresses carried in the TDLS Initiator STA Address field, TDLS Responder STA Address field, and BSSID field of the Link Identifier element carried in the TDLS Setup frame may be used instead for AAD and Nonce construction.

[0055] In one embodiment, TDLS can be extended to a virtual BSS (VBSS) architecture. A VBSS scenario might involve multiple APs in an ESS belonging to a "multi-AP group" forming a virtual BSS. Each AP may be associated with a corresponding multi-link device (MLD). Alternatively, the virtual BSS might consist of an MLD instead of multiple APs. APs in a multi-AP group may follow multi-AP cooperative behavior, which may be defined in future IEEE 802.11 standards. Such a multi-AP group may be referred to as a "cooperative AP group." A multi-AP group may form a virtual AP device or an extended MLD, where the APs or MLDs associated with the virtual device may not be collocated. A multi-AP group may also be a group of APs in Wi-Fi EasyMesh. A virtual BSS has an ID similar to a BSSID. Such an ID may be referred to as a "VBSSID" or a "multi-AP group ID." In this way, TDLS can be extended to an OBSS scenario, where peer STAs reside in a VBSS rather than the same BSS. For example, the TDLS initiator resides in one BSS and the TDLS responder resides in another BSS, but both are part of the same VBSS. In one implementation, if both STAs support enhanced TDLS, the BSSID field of the Link Identifier element sets the BSSID to the VBSSID. Enhanced TDLS capability is indicated by each capable STA during the TDLS discovery phase.

[0056] In the VBSS scenario, STA1 sends a TDLS Discovery Request frame encapsulated in an Ethertype 89-0d data frame in BSS1 with the following parameters: To DS field = 1, From DS field = 0, Address 1 field: RA = BSSID (e.g., AP1, or the AP associated with the TDLS initiator), Address 2 field: TA = STA1 (e.g., the address of the TDLS initiator), Address 3 field: DA = STA2 (e.g., the address of the TDLS responder in BSS1). AP1 (in BSS1) forwards the data frame to AP2 (e.g., the AP associated with the TDLS responder in BSS2) over the DS. AP1 and AP2 may belong to an ESS and are connected to a single common DS. While DS may be implemented in various ways (e.g., on wired or wireless backhaul), the source address (STA1 MAC address) and destination address (STA2 MAC address) information are communicated from AP1 to AP2, for example, via an Ethernet frame header on wired backhaul or a 4-address format data frame header on wireless backhaul. The 4-address format is used in AP-to-AP communication in some devices that support on-channel relaying and in some EasyMesh implementations. Furthermore, AP2 sends a data frame to STA2 in BSS2 with the following parameters: To DS field = 0, From DS field = 1, Address 1 field: RA = BSSID (AP1), Address 2 field: TA = STA1, Address 3 field: DA = STA2 (in BSS).

[0057] 18 shows a variation of a TDLS Discovery Response frame format 1800 that may be used with VBSSID configuration in accordance with one embodiment of the present disclosure. A Payload Type field 1802 indicates that the data frame is for TDLS. A Payload field 1804 includes a TDLS Discovery Response frame 1806 that includes a Category field 1808 set to TDLS, a TDLS Action field 1810 indicating that the frame 1806 is for a TDLS discovery response, and a Link Identifier element 1812. The Link Identifier element 1812 may indicate the VBSSID in the BSSID field 1814.

[0058] In one embodiment, AP1 (the AP associated with the TDLS initiator STA1) and AP2 (the AP associated with the TDLS responder STA2) may be co-located within a multi-BSSID set (e.g., within a single wireless router). For example, AP1 belongs to a main BSS (BSS1) with a broadcasted BSSID, and AP2 belongs to a guest BSS (BSS2) with an unbroadcasted BSSID, each belonging to a separate VLAN. In this case, although the APs do not belong to a single ESS, the barrier is lower than when the APs are independent because both STAs are aware of the common broadcasted BSSID and the data path from AP1 to AP2 is considered secure because both APs are implemented in a single device (e.g., a wireless router). In this scenario, the TDLS initiator may know from the multi-BSSID set information (signaling) that the data path from AP1 to AP2 and AP2 are secure. Signaling may be specified in the TDLS Discovery Request frame and other TDLS frames (e.g., using a frame format similar to Figures 7A and 7B) that indicates "enhanced TDLS" capability (e.g., in a reserved bit or element). For example, the BSSID field of the Link Identifier element is set to the transmitted BSSID. If the TDLS responder supports enhanced TDLS and the BSSID in the Link Identifier element is the transmitted BSSID, the responder may return a TDLS Discovery Response frame to the initiator. Similar signaling and criteria may also apply to TDLS setup or other TDLS processes. Additional security processing may be implemented because BSSs within a multi-BSSID set are intentionally isolated (e.g., for guest users).

[0059] 19 illustrates an example TDLS implementation 1900 with multiple BSSIDs in accordance with one embodiment of the present disclosure. AP 1908 (e.g., the AP associated with STA 1902), AP 1910 (e.g., the AP associated with STA 1904), and AP 1912 (e.g., the AP associated with STA 1906) are implemented in the same physical AP device within a wireless router 1914. AP 1908 is the AP with the transmitting BSSID, while APs 1910 and 1912 are APs with the non-transmitting BSSID. APs 1908 and 1910 belong to logically independent VLANs, but are allowed to forward traffic between each other. AP 1912 is isolated from other co-located APs by security policy; for example, forwarding between AP 1912 and AP 1908 and between AP 1912 and AP 1910 is not allowed. For example, a direct link can be established between STA1902 and STA1904 using enhanced TDLS, but a direct link cannot be established between STA1906 and STA1902, or between STA1906 and STA1904. The Neighbor Report or RNR approach for security verification can also be applied to this implementation. For example, each STA can collect trusted AP information (e.g., the route between its own BSS and peer BSS) from each associated AP.

[0060] 20 is a block diagram of a STA 2000 suitable for communication according to various embodiments of the present disclosure. The STA 2000 may be implemented as a non-AP STA or a STA suitable for enhanced TDLS according to various embodiments of the present disclosure. The STA 2000 may include a power supply 2002, memory 2004, a central processing unit (CPU) 2006, and a secondary storage device 2008. The STA 2000 may also include a wired interface 2010 and a wireless interface 2012 (including a MAC layer 2014 and a physical (PHY) layer 2016) for transmitting and receiving signals to and from other communication devices (e.g., other STAs / APs) for enhanced TDLS.

[0061] 21 shows a flow diagram 2100 illustrating a communication method according to various embodiments. In step 2102, a request frame is transmitted from a first wireless communication device to a second wireless communication device via a first AP associated with the first wireless communication device and a second AP associated with the second wireless communication device. The request frame indicates a request for peer-to-peer communication with the second wireless communication device. In step 2104, a response frame is received from the second wireless communication device in response to the request frame.

[0062] 22 illustrates a schematic partial cross-sectional view of a communication device 2200 that can be implemented for enhanced TDLS according to various embodiments. The communication device 2200 can be implemented as a STA or an AP according to various embodiments.

[0063] The various functions and operations of the communications device 2200 are arranged in layers according to a hierarchical model, where lower layers report to higher layers and receive instructions according to IEEE specifications, and for the sake of brevity, the details of the hierarchical model will not be described in this disclosure.

[0064] As shown in FIG. 22 , communications device 2200 may include circuitry 2214, at least one wireless transmitter 2202, at least one wireless receiver 2204, and multiple antennas 2212 (for simplicity, only one antenna is depicted in FIG. 22 for illustrative purposes). The circuitry may include at least one controller 2206 used for software- and hardware-assisted execution of tasks it is designed to perform, including controlling communications with one or more other devices in a wireless network. At least one controller 2206 may control at least one transmit signal generator 2208 that generates frames to be transmitted to one or more other STAs or APs via at least one wireless transmitter 2202, and at least one receive signal processor 2210 that processes frames received from one or more other STAs or APs via at least one wireless receiver 2204. At least one transmit signal generator 2208 and at least one receive signal processor 2210 may be standalone modules of communications device 2200 that communicate with at least one controller 2206 for the above functions. Alternatively, the at least one transmission signal generating unit 2208 and the at least one reception signal processing unit 2210 may be included in the at least one control unit 2206. It is apparent to those skilled in the art that the arrangement of these functional modules is flexible and may vary according to actual needs and / or requirements. Data processing, storage devices, and other related control devices may be provided in an appropriate circuit board and / or chipset.

[0065] In various embodiments, in operation, at least one wireless transmitter 2202, at least one wireless receiver 2204, and at least one antenna 2212 may be controlled by at least one controller 2206. Furthermore, while only one wireless transmitter 2202 is shown, it will be understood that there may be multiple such transmitters.

[0066] In various embodiments, in operation, at least one radio receiver 2204, together with at least one receive signal processor 2210, form the receiver portion of the communications device 2200. In operation, the receiver portion of the communications device 2200 provides the functionality required for enhanced TDLS. While only one radio receiver 2204 is shown, it will be understood that there may be multiple such receivers.

[0067] The communication device 2200, in operation, provides functionality required for enhanced TDLS. For example, the communication device 2200 may be a first wireless communication device. The transmitter 2202, in operation, may transmit a request frame to a second wireless communication device associated with a second AP for peer-to-peer communication. The receiver 2204, in operation, may receive a response frame from the second wireless communication device in response to the request frame.

[0068] The request frame may be a Tunneled direct-link setup (TDLS) Discovery Request frame, an Access Network Query Protocol (ANQP) request frame, or a TDLS Setup Request frame. The first AP may be connected to the second AP via a wireless backhaul or a wired backhaul. The first wireless communication device and the first AP may belong to a first basic service set (BSS), and the second wireless communication device and the second AP may belong to a second BSS different from the first BSS. The first and second wireless communication devices may be part of a virtual BSS (VBSS) that shares the same virtual BSSID (VBSSID).

[0069] In operation, the circuit 2214 may generate a request frame including a Link Identifier element, where the Link Identifier element indicates a first BSSID associated with the first wireless communication device, a second BSSID associated with the second wireless communication device, or both the first and second BSSIDs. The second wireless communication device may be a STA in an Extended Service Set (ESS), and the circuit 2214 may be further configured to generate a request frame including an FTE element for obtaining a TDLS peer key, where the FTE element indicates a MIC value, and to calculate the MIC value based on the Link Identifier element.

[0070] The first and second wireless communication devices may be part of a multi-BSSID set, and the first wireless communication device may be configured to collect, from the first AP, information about one or more APs along a path between a BSS associated with the first wireless communication device and a peer BSS associated with the second wireless communication device. The first and second APs may be part of multiple co-located APs, and these multiple co-located APs are implemented on the same physical AP device.

[0071] For example, the communication device 2200 may be a second wireless communication device associated with a second AP. The receiver 2204, in operation, may receive a request frame from the first wireless communication device via the first AP associated with the first wireless communication device and the second AP. The request frame indicates a request for peer-to-peer communication with the second wireless communication device. The transmitter 2202, in operation, may transmit a response frame to the first wireless communication device in response to the request frame.

[0072] The response frame may be a TDLS Discovery Response frame, an ANQP response frame, or a TDLS Setup Response frame. The response frame may be a TDLS Discovery Response frame, and the transmitter 2202 may be configured to transmit the response frame to the first wireless communication device via a direct link. The response frame may be a TDLS Setup Response frame in a payload of a data frame, and the transmitter 2202 may be configured to transmit the response frame to the first wireless communication device via the second and first APs.

[0073] The second wireless communication device may be an OBSS STA and may be further configured to, upon receiving the request frame, the TDLS Discovery Request frame, request information about neighboring BSSs from an associated AP. The information requested from the associated AP may include a Reduced Neighbor Report (RNR) or Neighbor Report element reporting a list of trusted APs.

[0074] In operation, the circuit 2214 may generate a response frame including a Link Identifier element indicating a first BSSID associated with the first wireless communication device, a second BSSID associated with the second wireless communication device, or both the first and second BSSIDs. The second wireless communication device may be a STA in an ESS, and the circuit 2214 may be further configured to generate a response frame including an FTE element for obtaining a TDLS peer key, where the FTE element indicates a MIC value, and to calculate the MIC value based on the Link Identifier element.

[0075] The present disclosure may be realized by software, hardware, or software in cooperation with hardware. Each functional block used in the description of the above embodiments may be partially or entirely realized as an LSI, which is an integrated circuit. Each process described in the above embodiments may be partially or entirely controlled by a single LSI or a combination of LSIs. The LSI may be formed as an individual chip, or a single chip may be formed to include some or all of the functional blocks. The LSI may include a data input / output unit coupled to it. Depending on the degree of integration, the LSI may also be referred to as an IC, system LSI, super LSI, ultra LSI, or system-on-chip (SoC). However, the technology for implementing an integrated circuit is not limited to LSI, and may be implemented using dedicated circuits, general-purpose processors, or dedicated processors. Furthermore, FPGAs (field programmable gate arrays), which can be programmed after LSI fabrication, and reconfigurable processors, which can reconfigure the connections and settings of circuit cells arranged within the LSI, may also be used. The present disclosure may be implemented using digital or analog processing. If, as a result of advances in semiconductor technology or other derivative technologies, LSI is replaced by a future integrated circuit technology, that future integrated circuit technology can be used to integrate functional blocks. Biotechnology is also applicable.

[0076] The present disclosure may be implemented in any type of apparatus, device, or system having a communication capability (collectively referred to as a communication device).

[0077] Non-limiting examples of such communication devices include telephones (e.g., mobile phones, smartphones), tablets, personal computers (PCs) (e.g., laptops, desktops, netbooks), cameras (e.g., digital still / video cameras), digital players (digital audio / video players), wearable devices (e.g., wearable cameras, smart watches, tracking devices, head-mounted displays (HMDs), smart glasses), game consoles, digital book readers, telemedicine (remote healthcare / medicine prescription) devices, vehicles (e.g., cars, airplanes, ships) that provide communication capabilities, and the like, including various combinations thereof.

[0078] Communication devices are not limited to portable or mobile devices, but also include non-portable or fixed equipment, devices, and systems of any kind, such as smart home devices (appliances, lighting equipment, smart meters or metering devices, control panels, etc.), vending machines, and any other "things" that may exist on an IoT (Internet of Things) network.

[0079] Communication may include, for example, exchanging data through cellular systems, wireless LAN systems, satellite systems, etc., and various combinations thereof.

[0080] A communications device also includes devices, such as controllers and sensors, coupled to a communications unit that perform the communications functions described in this disclosure, such as controllers and sensors that generate control and data signals used by the communications unit to perform the communications functions of the communications device.

[0081] Communication devices also include infrastructure facilities, such as base stations, access points, and any other apparatus, device, or system that communicate with or control the various non-limiting devices listed above.

[0082] Thus, it can be seen that the present embodiment provides a communication apparatus and method for enhanced TDLS.

[0083] While exemplary embodiments have been presented in the detailed description of the present embodiments, it should be understood that numerous variations exist. Furthermore, it should be understood that the exemplary embodiments are examples and are not intended to limit the scope, applicability, operation, or configuration of the present disclosure in any way. Rather, the above detailed description provides those skilled in the art with a convenient roadmap for implementing the exemplary embodiments, with the understanding that various changes can be made in the function and arrangement of steps described in the exemplary embodiments, and in the modules and structure of the devices described in the exemplary embodiments, without departing from the scope of the subject matter set forth in the appended claims.

Claims

1. a first wireless communication device associated with a first access point (AP), a transmitter that, in operation, transmits a request frame for peer-to-peer communication to a second wireless communication device associated with the second AP; a receiving unit configured to receive a response frame from the second wireless communication device in response to the request frame during operation; A first wireless communication device comprising:

2. The request frame is a Tunneled Direct-link Setup (TDLS) discovery request frame, an Access Network Query Protocol (ANQP) request frame, or a TDLS setup request frame. The first wireless communication device according to claim 1 .

3. The first AP is connected to the second AP via a wireless backhaul or a wired backhaul. The first wireless communication device according to claim 1 .

4. The first wireless communication device and the first AP belong to a first basic service set (BSS), and the second wireless communication device and the second AP belong to a second BSS different from the first BSS. The first wireless communication device according to claim 1 .

5. and further comprising circuitry that, when operational, generates the request frame including a link identifier element, the link identifier element indicating a first BSSID associated with the first wireless communication device, a second BSSID associated with the second wireless communication device, or both the first BSSID and the second BSSID. The first wireless communication device according to claim 1 .

6. the second wireless communication device is a STA in an Extended Service Set (ESS), The circuit further comprises: generating the request frame including an FTE element for obtaining a TDLS peer key, the FTE element indicating a MIC value; configured to calculate the MIC value based on the link identifier element; The first wireless communication device according to claim 5 .

7. the first and second wireless communication devices are part of a Virtual BSS (VBSS), and the Virtual BSSs share the same Virtual BSSID (VBSSID); The first wireless communication device according to claim 1 .

8. the first and second wireless communication devices are part of a multi-BSSID set, and the first wireless communication device is configured to collect information from the first AP about one or more APs along a path between a BSS associated with the first wireless communication device and a peer BSS associated with the second wireless communication device. The first wireless communication device according to claim 1 .

9. the first and second APs are part of a plurality of collocated APs, and the plurality of collocated APs are implemented in the same physical AP device; The first wireless communication device according to claim 8 .

10. a second wireless communication device associated with the second AP, a receiver that, during operation, receives a request frame from a first wireless communication device via a first AP associated with the first wireless communication device and the second AP, the request frame indicating a request for peer-to-peer communication with the second wireless communication device; a transmitter configured to, in operation, transmit a response frame to the first wireless communication device in response to the request frame; A second wireless communication device comprising:

11. The response frame is a TDLS discovery response frame, an ANQP response frame, or a TDLS setup response frame. The second wireless communication device according to claim 10.

12. the response frame is a TDLS discovery response frame, and the transmitter is configured to transmit the response frame to the first wireless communication device via a direct link; or the response frame is a TDLS setup response frame in a payload of a data frame, and the transmitter is configured to transmit the response frame to the first wireless communication device via the second AP and the first AP. The second wireless communication device according to claim 10.

13. the second wireless communication device is an OBSS STA, and is further configured to, upon receiving the request frame, request information about neighboring BSSs from an associated AP, wherein the request frame is a TDLS discovery request frame. The second wireless communication device according to claim 10.

14. The information requested from the associated AP includes a Reduced Neighbor Report (RNR), or Neighbor Report element, reporting a list of trusted APs. The second wireless communication device according to claim 13.

15. and further comprising circuitry that, when operational, generates the response frame including a link identifier element, the link identifier element indicating a first BSSID associated with the first wireless communication device, a second BSSID associated with the second wireless communication device, or both the first BSSID and the second BSSID. The second wireless communication device according to claim 10.

16. the second wireless communication device is a STA in an ESS; The circuit further comprises: generating the response frame including an FTE element for obtaining a TDLS peer key, the FTE element indicating a MIC value; configured to calculate the MIC value based on the link identifier element; The second wireless communication device according to claim 15.

17. 1. A communication method comprising: transmitting a request frame from a first wireless communication device to a second wireless communication device via a first AP associated with the first wireless communication device and a second AP associated with a second wireless communication device, the request frame indicating a request for peer-to-peer communication with the second wireless communication device; receiving a response frame from the second wireless communication device in response to the request frame; A communication method, including:

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