Bluetooth Basics: Communication and Security

[Inigo]

With numerous upgrades and enhancements of the standard tried the Bluetooth Special Interest Group (Bluetooth SIG or BSIG) to secure a successful future in the standard competition of radio technologies. The host controller interface (HCI) is a command interface to the baseband controller and link manager. It also provides access to the connection parameters. Typically, the HCI will be equated roughly with the TCP socket interface. The HCI and host developers to come into contact, because the commands are addressed in HCI provided by a Bluetooth HCI driver on the host. The Host Control Transport Layer, which is provided by the physical connection, connecting the two instances of HCI two communicating Bluetooth controller. The respective hosts are informed by asynchronous messages through the HCI events and are then responsible for parsing the possible events and carry out the necessary actions.

More details about the topic would be grateful..

[Janhavi4U]

The extensive command of the HCI are divided into the following groups: Generic Events, device setup, controller flow control, controller information, controller configuration, device discovery, connection setup, remote information, Synchronous Connections, Connection State, Piconet Structure, Quality of Service, Physical Links, host Flow Control, Link Information, Authentication and Encryption and testing. The devices responsible for finding commands (Device Discovery) may illustrate the scope and responsibilities of the HCI: Inquiry Command, Inquiry Result Event Inquiry Result with RSSI Event Inquiry Cancel Command, Periodic Inquiry Mode command, Exit Periodic Inquiry Mode command, Read Inquiry Scan Activity Command, Write Inquiry Scan Activity Command, Read Inquiry Scan Type Command, Write Inquiry Scan Type Command, Read and Write Inquiry Mode Command Mode Command Inquiry.

[yuppicide]

An important role in the course of a Bluetooth communication does the Service Discovery Protocol (SDP). Thus different Bluetooth devices, enabling the services and characteristics of the respective peer. Behind this system, plug-saving ideas: Thanks to SDP, the manufacturer must not obstruct the full Bluetooth stack in their devices, but their systems can build modular. If two devices establish a connection to each other, they can query the services available and build a connection based. SDP is an essential foundation to build spontaneous (ad hoc) networks.

[Norberd]

The RFCOMM standard is one of the major application protocols. It emulates a serial RS-232 interface and adapts to a part of the ETSI specification TS 7:10 for the Bluetooth standard to. This describes the point-to-point connection between two devices on the "serial port" air. For this reason, for example, and LAN connections over TCP / IP over serial point-to-Point Protocol (PPP) over RFCOMM implemented. RFCOMM has a similar meaning as the central wire RS232 interface. In this case, this means that the RFCOMM protocol is present in virtually all Bluetooth-stack implementations, and many proprietary applications are processed through here.

[Sanith]

Among the most abundant Bluetooth use cases include the coupling of different devices. In everyday life, likely, the coupling of a speakerphone and a telephone most often, such as a headset or speakerphone in cars. This indicates Telephony Control Service - Binary (TCS Binary) the Q.931 call setup and termination based on the ITU-T Recommendation. In addition, the Bluetooth SIG a set of so-called AT commands from the relevant ITU and ETSI specifications adopted to ensure the control of modems and mobile phones. In addition, and fax services. It should be noted that only the call is connected via the TCSBIN protocol and the L2CAP level takes place. The transfer of user data via the audio protocol that directly accesses a SCO link in the baseband.