| Bluetooth is the name given to a new technology | | | | transferring of information between devices:Core |
| standard using | | | | Protocols in Bluetooth:Baseband: The Baseband |
| short-range radio links, intended to replace the | | | | and Link Control layer enables the physical RF |
| cable(s) connecting | | | | link between Bluetooth forming a piconet. It |
| portable and fixed electronic devices. The | | | | provides two different |
| standard defines a uniform | | | | kind of physical links with their corresponding |
| structure for a wide range of devices to | | | | baseband packets, |
| communicate with each other.Its important | | | | Synchronous Connection-Oriented and |
| features of Bluetooth are robustness, low | | | | Asynchronous Connectionless which |
| complexity, | | | | can be transmitted in a multiplexing manner on |
| low power and low cost. Bluetooth is considered | | | | the same RF |
| a wireless PAN | | | | link.Asynchronous Connectionless (ACL) packets |
| technology that offers fast and reliable | | | | are used for the |
| transmission for both voice | | | | transmission of data only while Synchronous |
| and data. Bluetooth offers wireless access to | | | | Connection-Oriented can |
| LANs, PSTN, the mobile | | | | contain either audio or a combination of audio and |
| phone network and the Internet for home or | | | | information.Link Manager Protocol: The link |
| office and other hand held | | | | manager protocol is responsible for |
| devices.A complete Bluetooth system will require | | | | link set-up between Bluetooth devices. This |
| these elements:An RF portion for collecting and | | | | includes setting up of |
| sending data or information: | | | | security functions like authentication and |
| A module with a baseband microprocessor for | | | | encryption by generating, |
| processing function | | | | exchanging and checking of link and encryption |
| Memory module | | | | keys and the control, |
| An interface to the electronic device (such as a | | | | negotiation of baseband packet sizes and duty |
| mobile phone, camera, or PC)The lower-layer | | | | cycles of the Bluetooth |
| Bluetooth protocols are normally embedded in the | | | | radio device, and the receiving device on the |
| baseband module, and the host processor must | | | | other end.Logical Link Control and Adaptation |
| support the upper-layer | | | | Protocol: The Bluetooth logical |
| protocols (like file transfer). In other words, the | | | | link control and adaptation protocol (L2CAP) |
| RF/baseband | | | | adapts upper layer |
| solution provides the means to communicate | | | | protocols over the baseband. It can be thought |
| with the host, but need to | | | | to work in parallel |
| implement a connection interface, as well as any | | | | with LMP in difference that L2CAP provides |
| upper-layer | | | | services to the upper layer |
| protocols, to use applications supported by the | | | | when the payload data is never sent at LMP |
| final product.The higher/upper layers of the | | | | messages.Service Discovery Protocol: Using SDP, |
| Bluetooth technology called as the | | | | device information, services |
| Bluetooth profiles and these are nothing but a set | | | | and the characteristics of the services can be |
| of protocols. These | | | | queried and after that, |
| protocols are optimized for particular applications. | | | | a connection between two or more Bluetooth |
| In the case of | | | | devices can be established.Telephony and Cable |
| file transfer between two devices, it requires | | | | Replacement Protocol:Telephony Control protocol: |
| interoperability among | | | | Binary (TCS Binary or TCS BIN), a bit |
| devices. Each of the linked devices needs to | | | | oriented protocol, defines the call control signaling |
| have similar applications | | | | for the |
| ensures interoperability across a spectrum of | | | | establishment of speech and data calls between |
| devices.The Bluetooth stack: It has the following | | | | Bluetooth devices.RFCOMM:It is a serial line |
| components:RF portion for reception and | | | | emulation protocol and is based on ETSI |
| transmission | | | | 07.10 ( European Telecommunications |
| Baseband portion with micro controller | | | | Standardization Institute ) |
| Link control unit | | | | specification. This protocol emulates RS-232 |
| Link manager to support lower-layer protocols | | | | control and data signals |
| Interface to the host device | | | | over Bluetooth baseband, providing both |
| Host processor to support upper-layer protocols | | | | transport capabilities for |
| L2CAP to support upper-layer protocolsThe radio | | | | upper level services that use serial line as |
| frequency (RF) portion provides the digital | | | | transport mechanism.Adopted Protocols:PPP:PPP is |
| signal-processing (DSP) component of the | | | | the IETF Point-to-Point Protocol (Internet |
| system, | | | | Engineering Task |
| and the baseband micro controller processes | | | | Force, IETF Directory List of RFCs) and |
| these signals. | | | | PPP-Networking is the means of |
| The link controller handles all the baseband | | | | taking IP packets to/from the PPP layer and |
| functions and supports | | | | placing them onto the LAN.TCP/UDP/IP: TCP/IP |
| the link manager. It sends and receives data, | | | | PPP is used for the all Internet Bridge usage |
| identifies the sending | | | | scenarios in Bluetooth 1.0 and for OBEX in future |
| device, performs authentication, and determines | | | | versions. UDP/IP/PPP |
| the type of frame to | | | | is also available as transport for WAP.OBEX |
| use for sending a transmissions. The link | | | | Protocol: IrOBEX (Short name is OBEX) is a |
| controller also directs how | | | | session protocol developed |
| devices listen for transmissions from other | | | | by the Infrared Data Association (IrDA) to |
| devices and can move | | | | exchange data in a simple and automatic |
| devices into sleep state in order to save | | | | way.Advantages: Using peer-to-peer connectivity, |
| power.The link manager, located on top of the link | | | | Bluetooth technology |
| controller, controls | | | | simplifies personal area wireless connections, |
| setup, authentication, link configuration, and other | | | | enabling all digital |
| low-level | | | | devices to communicate automaticaly. Bluetooth |
| protocols. Together, the baseband and the link | | | | technology also |
| manager establish | | | | provides fast, secure voice and data |
| connections for the network.The host controller | | | | transmissions. The range for |
| interface (HCI) communicates the lower-layer | | | | connectivity is less than 10 meters, and line of |
| protocols to the host device(Like mobile phone, | | | | sight is not required. |
| hand held PC etc).The host contains a | | | | The Bluetooth radio unit can functions even in |
| processor.L2CAP: it supports the upper-layer | | | | noisy radio environments, |
| protocols and communicates with | | | | ensuring audible voice transmissions in severe |
| the lower layers. The Higher/upper-layer | | | | conditions. It can |
| protocols consist of service-specific applications | | | | protect data by using error-correction methods |
| that must be integrated into the host application | | | | and provides a high |
| as explained above. RFCOMM protocol, which | | | | transmission rate. It is possible encryption and |
| allows for the emulation of serial ports over the | | | | authentication for |
| L2CAP, which is also an important part of | | | | privacy in the transmitted data.In Bluetooth ad |
| Bluetooth.The Service Discovery Protocol (SDP) | | | | hoc networking enables personal devices to |
| gives the required services and the properties and | | | | automatically exchange information and |
| characteristic of the service that a particular | | | | synchronize with each other.Jith is an Electrical and |
| Bluetooth device is made for.The ACL Link: | | | | Electronic Engineer by profession from Southern |
| Bluetooth uses five logical channels to support | | | | india. |