U-connectXpress, Bluetooth Security, Application Note
u-connectXpressBluetooth securityApplication noteAbstractThis application note describes the features and supported security modes in u-blox short rangestand-alone modules.UBX-16022676 - R06C1-Publicwww.u-blox.com
u-connectXpress Bluetooth security - Application noteDocument informationTitleu-connectXpressSubtitleBluetooth securityDocument typeApplication noteDocument numberUBX-16022676Revision and dateR06Disclosure restrictionC1-Public4-Feb-2021This document applies to the following products:Product nameu-connectXpress software versionANNA-B112AllNINA-B1114.0.0 or laterNINA-B1124.0.0 or lNINA-W152AllNINA-W1563.1.0 or laterODIN-W2605.0.0 or laterODIN-W2625.0.0 or laterODIN-W2635.0.0 or lateru-blox or third parties may hold intellectual property rights in the products, names, logos and designs included in thisdocument. Copying, reproduction, modification or disclosure to third parties of this document or any part thereof is onlypermitted with the express written permission of u-blox.The information contained herein is provided “as is” and u-blox assumes no liability for its use. No warranty, either express orimplied, is given, including but not limited to, with respect to the accuracy, correctness, reliability and fitness for a particularpurpose of the information. This document may be revised by u-blox at any time without notice. For the most recentdocuments, visit www.u-blox.com.Copyright u-blox AG.UBX-16022676 - R06C1-PublicDocument informationPage 2 of 19
u-connectXpress Bluetooth security - Application noteContentsDocument information . 2Contents . 31Introduction . 41.1 Documentation . 42Introduction to secure simple pairing . 53Low energy secure connections . 63.1 Introduction . 63.2 Payment Card Industry security requirements . 64Security modes . 74.1 Introduction . 74.2 Bluetooth low energy security modes and levels. 74.2.1Low energy security mode 1 . 74.2.2Low energy security mode 2 . 74.3 Bluetooth BR/EDR security modes and levels . 74.4 Security mode 1: Security Disabled Auto Accept . 84.5 Security mode 2: Just Works . 84.6 Security mode 3: Display Only . 94.7 Security mode 4: Display Yes/No . 94.8 Security mode 5: Keyboard Only . 94.9 Security mode 6: Out Of Band . 94.10 Fixed pin Bluetooth 2.0 .105Supported use cases . 116Sample use cases . 126.1 Cellphone and headset pairing .126.2 PC and keyboard pairing .126.3 PC and cellphone pairing .137Security in s-center . 14Appendix . 15AKnown vulnerabilities. 15A.1 CVE-2019-9506, “KNOB”-attack . 15BGlossary . 16Related documents . 17Revision history . 18Contact. 19UBX-16022676 - R06C1-PublicContentsPage 3 of 19
u-connectXpress Bluetooth security - Application note1IntroductionThis document describes: Secure Simple Pairingu-connect security solutions for Bluetooth BR/EDR and Bluetooth Low Energy (LE)Bluetooth LE secure connectionsSome common user scenariosBluetooth security in u-blox s-center toolTo see which features are applicable for each product, refer to the Product Summary documentfor the product in question. See Related documents.1.1 Documentation The s-center user guide [2] describes how to use s-center to configure theu-blox short range modules, and the u-connectXpress user guide [9] contains details of the varioususe cases. The u-connect AT commands manual [1] contains a detailed description of the supported ATcommands. The product summary for each applicable product describes which security features are applicablefor each product.o ODIN-W2 product summary [3]o NINA-W15 product summary [12]o NINA-B1 product summary [4]o NINA-B2 product summary [5]o NINA-B30 product summary [6]o NINA-B31 product summary [7]o ANNA-B112 product summary [8]UBX-16022676 - R06IntroductionPage 4 of 19
u-connectXpress Bluetooth security - Application note2Introduction to secure simple pairingSecure Simple Pairing was introduced in Bluetooth v4.0.The main goals for Secure Simple Paring are: To simplify the pairing process from the end user’s point of view To maintain or improve the security in BluetoothSecure Simple Pairing aims to improve protection against passive eavesdropping, using Elliptic CurveDiffie-Hellman (ECDH) public key cryptography. This means about 95 bits of entropy, which exceedsthe requirements of the Bluetooth SIM Access Profile (profile with the strongest securityrequirements).Secure Simple Pairing also protects the user from “man-in-the-middle attacks” (activeeavesdropping) with a goal of offering a 1 in 1,000,000 risk that any man-in-the-middle could mounta successful attack. This probability is considered low enough to meet the FIPS 140-29 requirementsfor authentication.Consider the following three main use cases for Secure Simple Pairing:1. Just Works: Intended for cellphone-to-headset (or similar) pairing scenarios, where one devicehas neither display nor keyboard. In these instances, the Bluetooth device only allows pairingduring the time that the phone and headset are performing the pairing procedure. During thistime, all pairing attempts are automatically accepted.2. Numeric Comparison: Intended for cellphone-to-PC (or similar) pairing scenarios, where the twoconnecting devices both include some interactive mechanism (display, keyboard, switch, orsimilar) that allows the respective users to confirm either “yes” or “no” to a connection request.To make the connection, a common six-digit confirmation number is displayed for the respectiveusers of both devices. Pairing between the two devices is only completed after the users haveconfirmed that the numbers match. The pairing is aborted if the numbers do not match.3. Passkey Entry: Intended for keyboard-to-PC (or similar) pairing scenarios, where only one of theconnecting devices has input (but no output) capability and the other has output (but no input)capability. The device with output capability displays a six-digit confirmation number that mustbe confirmed by the user of the device with input capability. The pairing of the two devices is onlymade after the user has confirmed that the number is correct.The pairing arrangements for connecting devices that support different Bluetooth versions differ: Bluetooth 2.1 (or newer) devices pairing with Bluetooth 2.0 (or earlier) devices must connect inaccordance with Bluetooth 2.0 (or earlier) security protocols. This means that Secure SimplePairing cannot be used. Bluetooth 2.1 (or newer) devices connecting with similarly versioned devices must connect inaccordance with Secure Simple Pairing protocols and cannot use Bluetooth 2.0 (or earlier)security mechanisms.UBX-16022676 - R06Introduction to secure simple pairingPage 5 of 19
u-connectXpress Bluetooth security - Application note3Low energy secure connections3.1 IntroductionBluetooth Low Energy (LE) Secure Connection is an improved pairing mechanism introduced inBluetooth v4.2. It uses Elliptic Curve Diffie Hellman (ECDH) encryption for key generation and providesstronger protection against Man-In-The-Middle (MITM) attacks. This encryption method uses publicprivate key pairs for exchanging the Long Term Key between paired devices.Low energy secure connections can only be used if both devices support this feature. If only one devicesupports low energy secure connections, the devices must connect using legacy low energy pairinginstead.In Secure Connections Only Mode, the device rejects both new outgoing and incoming service levelconnections when the other device does not support low energy secure connections.Secure connections can be enabled by the following AT command:AT UBTST 1A device is set in the Secure Connections Only Mode by setting it in FIPS only mode:AT UBTST 2Low energy secure connections support the following four association models: Just worksNumeric Comparison (only in Low Energy Secure Connections)Passkey Entry(Out of Band (OOB)) Not supported by u-connectXpressIn order to use the Numeric comparison association model, the IO capabilities of the involved devicesmust be matched as specified in Table 1.Bluetooth low energyInitiatorNo sec(1)Just Works (2) Display Only(3)Display Y/N(4)Keyboard Only(5)Out Of Band(6)Responder No sec (1)Just Works (2)Display Only (3)Display Y/N (4)NumericcomparisonKeyboard Only (5)Out Of Band (6)Table 1 IO Capabilities for numeric comparison3.2 Payment card industry security requirementsIn order to set up a device to be compatible with Payment Card Industry (PCI) security requirements,it is essential to fulfill the following requirements: Low Energy Security Mode 1 Level 4 only Just Works association model cannot be used.This means that a u-blox module must be set in the FIPS-only mode (AT UBTST 2) and it is not possibleto use the Just Works security mode. See the u-connectXpress user guide ([9]) and PCI SecurityStandards Council ([11]) for more information.UBX-16022676 - R06Low energy secure connectionsPage 6 of 19
u-connectXpress Bluetooth security - Application note4Security modes4.1 IntroductionNote that the Security Modes in u-blox u-connect products do not directly correspond to the Securitymodes or the Security levels of the Bluetooth specification.This chapter provides an overview of the different security modes in u-blox u-connect products, anda mapping to the Bluetooth standard. Sections 4.2 and 4.3 give an introduction to the securityfeatures of the Bluetooth standard while the sections that follow describe the security modes used inu-blox u-connect products.4.2 Bluetooth low energy security modes and levelsThe security modes and levels described here are according to the Bluetooth standard (reference[10]), volume 3, part C, chapter 10.2.Bluetooth low energy has two Security Modes with different levels.4.2.1 Low energy security mode 1Low energy security mode 1 uses data encryption but no signing of data. It has the following securitylevels:1.2.3.4.No security (No authentication and no encryption)Unauthenticated pairing with encryptionAuthenticated pairing with encryptionAuthenticated Bluetooth LE Secure Connections pairing with encryption using a 128-bit strengthencryption key (see chapter 3 for more information).All of these security levels are applicable for u-blox u-connect products. Please see the productspecification and u-connect AT commands manual [1] for details on each product.4.2.2 Low energy security mode 2Low energy security mode 2 uses data signing. It has two security levels:1. Unauthenticated pairing with data signing2. Authenticated pairing with data signingLow energy security mode 2 is not used in u-blox products.4.3 Bluetooth BR/EDR security modes and levelsDifferent security modes are available to support all kinds of use cases regarding the pairingprocedure. Each mode is specified for Bluetooth v2.0 (or earlier) and v2.1 (or newer) security. This isto comply with the version in the remote device. If the remote device supports only Bluetooth 2.0 (orearlier), a Bluetooth 2.1 (or newer) device must conform to the Bluetooth 2.0 security algorithms.All security modes except security Modes 1 and 2 for Bluetooth 2.0 devices use encryption. Thesecurity modes 1 and 2 (Security Disabled) for Bluetooth 2.1 still use encryption. The encryptionalgorithm is a 128-bit cipher called E0.For secure connections, 128-bit equivalent strength for link and encryption keys are required usingFIPS approved algorithms (E0 not allowed, SAFER not allowed, and P-192 not allowed).UBX-16022676 - R06Security modesPage 7 of 19
u-connectXpress Bluetooth security - Application noteThe security modes 1 and 2 are implemented to keep the behavior similar to the previous versions ofu-blox Bluetooth products.The Display Only, Display Yes/No, and Keyboard Only modes (modes 3, 4 and 5) can only be used inthe AT or Extended Data mode since it requires user interaction (AT commands and events). Note that the Security Modes in u-blox u-connect products do not directly correspond to theSecurity modes or the Security levels of the Bluetooth specification.Security level required for serviceLink key typerequired forremote devicesLink key typerequired for pre-v2.1remote deviceCommentsLevel 4 MITM protection required Encryption required User interaction acceptableAuthenticatedNA(P-256 based SecureSimple Pairing and SecureAuthentication)Level 3 MITM protection required Encryption required User interaction acceptableAuthenticatedCombination (16-digit High SecurityPIN recommended)Level 2 MITM protection not necessary Encryption desiredUnauthenticatedCombinationMedium SecurityLevel 1 MITM protection not necessary Encryption not necessary1 Minimal user interaction desiredUnauthenticatedNoneLow SecurityLevel 0 MITM protection not necessary Encryption not necessary No user interaction desiredNoneNonePermitted only for SDP andservice data sent via either L2CAPfixed signaling channels or theL2CAP connectionless channel toPSMs that correspond to theservice class UUIDs, which areallowed to utilize Level 0Highest SecurityOnly possible when both devicessupport Secure ConnectionsTable 2: Security level mapping to link key requirements, according to the Bluetooth standard4.4 Security mode 1: Security Disabled Auto AcceptFor security modes 1 and 2, pairing will be auto accepted and the link keys are generated without usinga passkey; the pairing devices must allow pairing. This corresponds to Bluetooth v2.1 Security Mode 4 Level 1 in the Bluetooth specification, whichis also shown in Table 2.4.5 Security mode 2: Just WorksJust Works is the configuration to use when no user interaction can be done and all possible pairingcomparisons should be done.The I/O capability is set to “no input/no output” and no authentication is required. The Bluetoothdevice replies to all pairing requests. If the remote device has a higher authentication requirement,the remote device takes the decision whether this is an acceptable bond.Pairing is initially disabled and needs to be explicitly enabled using switch SW2. You set the JustWorks configuration with the AT command AT UBTPM or by pressing the “external connect” button for5 seconds. Pressing the button enables the pairing for 60 seconds during which time signal BLUE(typically connected to an LED) toggles/flashes.UBX-16022676 - R06Security modesPage 8 of 19
u-connectXpress Bluetooth security - Application note This corresponds to Bluetooth v2.1 Security Mode 4, Level 2 in the Bluetooth specification, whichis also shown in Table 2.4.6 Security mode 3: Display OnlyThe security mode 3 suits devices that support output capabilities. It is intended to be used togetherwith remote devices that support input capabilities. MITM protection is required to get a successfulbond.When pairing is initiated, the User Passkey Display event ( UUBTUPD) will be sent to the host with a sixdigit number. The local host shall then display the number so that it can be entered at the remotedevice. This corresponds to Bluetooth 2.1 Security Mode 4 Level 3 in the Bluetooth specification, which isalso shown in Table 2.4.7 Security mode 4: Display Yes/NoThe security mode 4 suits devices with both output and input capabilities. It is intended to be usedwith remote devices supporting both output and input capabilities. MITM protection is required to geta successful bond.When pairing is initiated, the User Confirmation event ( UUBTUC) will be sent to the host with asix-digit number and the Bluetooth address of the remote device. The host shall then display thenumber and let the user accept or reject the pairing attempt by calling the User Confirmationcommand (AT UBTUC). This corresponds to Bluetooth v2.1 Security Mode 4 Level 3 in the Bluetooth specification, whichis also shown in Table 2.4.8 Security mode 5: Keyboard OnlyThe security mode 5 suits devices with input capabilities. It is intended to be used with remote devicesthat support output capabilities. MITM protection is required to get a successful bond.When pairing is initiated, the User Passkey Entry event ( UUBTUPE) is sent to the host with theBluetooth address of the remote device. The User Passkey Entry command (AT UBTUPE) shall then becalled with the six-digit number that is displayed at the remote device. This corresponds to Bluetooth 2.1 Security Mode 4 Level 3 in the Bluetooth specification, which isalso shown in Table 2.4.9 Security mode 6: Out Of BandThe security mode 6 is suitable if both devices can transmit and/or receive data over an out-of-bandchannel. It is indicated by a one field in the Pairing Request/Response message (OOB Data Flag) ifOOB data is available. Both devices must set the OOB flag in order to use OOB pairing.Before pairing is initiated, a temporary key is initiated on one side, which must serve as an input onthe other side.AT UBTOTK 0AT UBTOTK? UBTOTK:9A4F4D0377ED71B023BD82C16499609AThis key needs to be set on the other side before pairing can be performed.AT UBTOTK 1,9A4F4D0377ED71B023BD82C16499609AUBX-16022676 - R06Security modesPage 9 of 19
u-connectXpress Bluetooth security - Application notePairing is possible now using the Bond (AT UBTB) command. Use NFC as the typical OOB medium.4.10 Fixed pin Bluetooth 2.0Two Bluetooth 2.1 EDR devices acting as Keyboard Only devices will work similarly to the Bluetooth2.0 pairing using a fixed pin. Instead of having a user enter the six-digit numerical passkey, a fixedpasskey stored in flash is used (AT UBTSM with the Bluetooth 2.0 fixed pin option must be enabled).The passkey consists of 1 to 6 numerical digits.This security mode is intended for use cases between two Bluetooth 2.1 EDR products where bothare configured for Fixed Pin security.Pairing will then be automatic (no user interaction) using the stored passkey (AT UBTSM) and a link keyis generated. This corresponds to Bluetooth v2.1 Security Mode 4 Level 3 in the Bluetooth specification, whichis also shown in Table 2. In Bluetooth v2.0, it is called a “pin code”. In Bluetooth 2.1, it is called a “passkey”.UBX-16022676 - R06Security modesPage 10 of 19
u-connectXpress Bluetooth security - Application note5Supported use casesMan in the middle protection is required for the security modes 3 (Display Only), 4 (Display Yes/No),and 5 (Keyboard Only). This means it is not possible to pair with devices having security modes 1 (autoaccept) or 2 (Just Works) without authentication, which is in accordance with the Bluetooth CoreSpecification ([10]).Table 3 and Table 4 show the combinations where pairing is possible.When the device is configured with a required MITM protection, the pairing will only be successful ifthe remote side also requires authentication. In the two tables below, “MITM” means not supported due to Man in the Middle attack risk.Bluetooth BR/EDRResponder No sec (1)InitiatorNo sec (1)Just Works (2)Display Only (3)Display Y/N (4)Keyboard Only (5)YesYes1MITMMITMMITMJust Works (2)Yes1Yes1MITMMITMMITMDisplay Only (3)MITMMITMMITMMITMYes3Display Y/N (4)MITMMITMMITMYes2Yes3Keyboard Only (5)MITMMITMYes4Yes4Yes51Table 3: Bluetooth BR/EDR association modelsBluetooth Low EnergyInitiatorNo sec (1) Just Works (2) Display Only (3) Display Y/N (4)Responder No sec (1)Out Of Band (6)MITMMITMMITMMITMYes1Yes1MITMMITMMITMMITMDisplay Only (3)MITMMITMMITMMITMYes3MITMDisplay Y/N (4)MITMMITMMITM(MITM)8Yes3MITMKeyboard Only (5) MITMMITMYesYesYes5Yes7Out Of Band (6)MITMMITMYes7Yes6YesMITMYesKeyboard Only (5)Just Works (2)1144MITMTable 4: Bluetooth Low Energy association modelsPairing is possible in the following scenarios:1when both devices have pairing enabled (AT UBTPM).when receiving UUBTUC event on both initiator and responder and both sides accept the incoming passkey by sendingAT UBTUC.2when the initiator receives UUBTUPE event and accepts it by sending AT UBTUPE with passkey from the UUBTUPD event onresponder side.34when the responder receives UUBTUPE event and accepts it by sending AT UBTUPE with passkey from the UUBTUPD eventon initiator side.5when both initiator and responder receive a UUBTUPE event and both devices send equal random passkey in AT UBTUPEcommand.6when OOB temporary keys match7when there is a fallback to Just Works association model due to mismatching capabilities; see Bluetooth Core Specification[10], Vol3, Part H, Table 2.7 and 2.8 (v. 5.1). This fallback is not valid in Low Energy Secure Connections mode.when Low Energy Secure Connections is enabled. This combination will result in the Numeric Comparison association model;see chapter 3.8UBX-16022676 - R06Supported use casesPage 11 of 19
u-connectXpress Bluetooth security - Application note6Sample use cases6.1 Cellphone and headset pairingJust Works is the security mode recommended for having an easy and sufficient security level. Whenat least one side does not have any input and output capabilities (for example, in the cellphone pairedwith headset scenario) and Bluetooth 2.1 EDR security must be used, the Just Works security mode(security mode 2) is the only applicable security level.In this security mode, the u-blox Bluetooth device is invisible for pairing until pairing is enabled.AT Mode1. Enable pairing using the Pairing Mode command (AT UBTPM)2. Initiate pairing by connecting or bonding (AT UBTB)3. Disable pairing using the Pairing Mode command (AT UBTPM)Data Mode1. Enable pairing for 60 seconds by pressing the "External Connect" button for at least 5 seconds.The LED will blink when the 5 seconds has elapsed and continuously during the time when themodule has pairing enabled.2. Initiate pairing by connecting.3. After 60 seconds, pairing will be disabled automatically. Pairing must be enabled on both the initiator and the responder sides.6.2 PC and keyboard pairingThe PC paired with keyboard use case is intended when only one device has input capabilities (forexample, the keyboard) and the other device has output capabilities (for example, the PC or cellphone).Hence, the keyboard side is configured with the security mode 5 (keyboard only) and the PC side isconfigured for the security mode 3 (display only).In the figure below, the Bond command (AT UBTB) is used to initiate pairing and the Bond event( UUBTB) is sent to inform the result of the pairing attempt. The Bond command (AT UBTB) can becalled from either side.When the PC gets the User Passkey Display event ( UUBTUPD), it must display the six-digit numberreceived in the event. Simultaneously, the keyboard side will get the User Passkey Entry event( UUBTUPE) to inform the host to insert a six-digit number using the User Passkey Entry command(AT UBTUPE). If the inserted number is the same as the displayed number, pairing is successful.UBX-16022676 - R06Sample use casesPage 12 of 19
u-connectXpress Bluetooth security - Application noteThe above sample describes a case where neither the PC nor the keyboard supports Bluetooth andboth sides use a u-blox Bluetooth device for Bluetooth support. This case can be separated into twouse cases where either the PC or the keyboard has built-in Bluetooth without the need of a Bluetoothdevice.6.3 PC and cellphone pairingThe PC paired with cellphone use case is intended where both the local and remote device have inputcapabilities as well as output capabilities (for example, PC or Cellphone). Hence, both sides areconfigured with the security mode 4 (Display Yes/No).In the figure below, the Bond command (AT UBTB) is used to initiate pairing and the Bond event ( UBTB)is sent to inform the result of the pairing attempt. The Bond command (AT UBTB) could be called fromeither side.For both the PC and Cellphone, when it gets the User Confirmation event ( UUBTUC), it must displaythe six-digit number and allow for the user to accept/reject pairing. The user input is then sent to theu-blox Bluetooth device using the User Confirmation command (AT UBTUC). When the users on bothsides accept the pairing, it is successful.UBX-16022676 - R06Sample use casesPage 13 of 19
u-connectXpress Bluetooth security - Application note7Security in s-centers-center implements support to configure the security mode and initiate bonding. For the securitymodes Display Only, Display Yes/No, and Keyboard Only, s-center provides some additional support.Keyboard OnlyAfter receiving the keyboard-only event UUBTUPE, the user enters the remote Bluetooth address andthe received six-digit passkey number in the window and clicks OK to send the AT UBTUPE command.Display Yes/NoAfter receiving the keyboard-only event UUBTUPE, the user must verify that the passkey is correct.The user enters the remote Bluetooth address and clicks OK to send the AT UBTUC command. The usermay accept or reject the pairing attempt.Display OnlyA six-digit number, which may be read or copied is received in the UUBTUPD event, and should be usedon the remote device.Example: UUBTUPD:78A5042F673Dp,209471UBX-16022676 - R06Security in s-centerPage 14 of 19
u-connectXpress Bluetooth security - Application noteAppendixA Known vulnerabilitiesIn the following sub chapters the status of some known issues are listed. Please see reference [14] foran online list of issues and information on how to report security issues.A.1 CVE-2019-9506, B1NoN/ANINA-B1NoN/ANINA-B2v1.0.xv2.1.0 onwardsNINA-B3NoN/ANINA-W15v1.0.xv2.1.0 onwardsODIN-W2v1.0.x – v7.1.x (partly)ODIN-W2 up to v7.1.x requires a minimum key length of 5 bytes.UBX-16022676 - R06AppendixPage 15 of 19
u-connectXpress Bluetooth security - Application noteB GlossaryAbbreviationDefinitionBR/EDRBasic Rate/Enhanced Data RateEVKEvaluation KitMITMMan in the MiddleN/ANot ApplicableNFCNear Field CommunicationOOBOut of BandPCIPayment Card IndustryTable 5: Explanation of the abbreviations and terms usedUBX-16022676 - R06AppendixPage 16 of 19
u-connectXpress Bluetooth security - Application noteRelated 3][14][15] u-connectXpress AT commands manual, UBX-14044127s-center use
The pairing arrangements for connecting devices that support different Bluetooth v ersions differ: Bluetooth 2.1 (or newer ) devices pairing with Bluetooth 2.0 (or earlier) device s must connect in accordance with Bluetooth 2.0 (or earlier) security protocols.
Using your Bluetooth headset with the Logitech wireless hub 2 Start the Bluetooth Setup Wizard in one of three ways: Press the Connect button on your Bluetooth wireless hub.-or- Right-click the Bluetooth icon, , in the Windows taskbar and select Add a Bluetooth Device from the menu displayed.-or- Select Add a Bluetooth Device from the Bluetooth Tasks panel in the My Bluetooth
Targus USB Ultra-Mini Bluetooth 2.0 Adapter with EDR Basic Operations Start or Stop Bluetooth (for Windows 2000/ XP only) To start Bluetooth In the Windows system tray, right-click the Bluetooth icon and select Start the Bluetooth Device.The Bluetooth icon is blue in color with a white insert when the Bluetooth software is running. To stop Bluetooth
Bluetooth Hands-Free Bluetooth Hands-Free When connecting a Bluetooth device (mobile phone) to the vehicle's Bluetooth unit via radio wave transmission, calls can be made or received. For example, even if a Bluetooth device is in your coat pocket, a call can be made without taking the Bluetooth device out and operating it directly.
BLUETOOTH - Bluetooth Function 1. Bluetooth Function 1.1. Registering a Bluetooth Mobile Phone or Music Player 1.1.1. Pairing Mode A Bluetooth connection must first be established between your Bluetooth mobile phone
Settings Bluetooth Bluetooth OPPO R9s huawei Avantree HS134 Connected Bose Bluetooth Audio. Not Connected Now discoverable as “iPhone(2)” MY DEVICES OTHER DEVICES To pair an Apple Watch with your iPhone, go to the Watch app. 4:30 4G Settings Bluetooth Bluetooth OPPO R9s huawei Avantree HS134 Not Connected Bose Bluetooth Audio. Not Connected
entertainment audio hub! As a Bluetooth transmitter to Bluetooth-enable your TV or AV receiver, to stream audio to your Bluetooth headphones or speakers. As a Bluetooth receiver to Bluetooth-enable your traditional non-wireless music system. It supports both wireless (Bluetooth) and wired (bypass) modes simultaneously.
When using the Bluetooth device in the pocket of the chest or pants, or a bag while listening to the audio. This is because the human body blocks the Move the Bluetooth device to a position where there is no obstacle, such as a human body, to Bluetooth communication when using the Bluetooth device in a pocket or a bag.
1) General characters, structure, reproduction and classification of algae (Fritsch) 2) Cyanobacteria : General characters, cell structure their significance as biofertilizers with special reference to Oscillatoria, Nostoc and Anabaena.
