A Brief Explanation of Bluetooth Technology - Term Paper Example

Student’s Name Your Instructor’s name The Course 06 May 2011 Brief explanation of Bluetooth technology Bluetooth technology is an open standard used for short-range radio frequency communication between two or more devices. Bluetooth connection enables a formation of a Wireless Personal Area Network (WPAN) which is essentially known as an ad hoc network or a peer-to peer (P2P) network. Bluetooth technology has found usage in a wide range of devices including cellular phones, laptops, automobiles, personal digital assistants and headsets. It is thus possible to form an ad hoc network between many different devices and create a wireless file sharing process because of the Bluetooth interoperability (Scarfone 2). Bluetooth also enables secure voice and data transfer between devices that are Bluetooth enabled. When two or more devices are connected creating a Bluetooth network, it is usually referred as a piconet. Bluetooth standardization is within IEEE 802.15 Working Group used in Wireless Area Networks which was created in 1999 and thus considered IEEE 802.15.1-2002. The frequency range of Bluetooth is about 2.4 Gigahertz (GHz) which is unlicensed. Because this range of frequency is crowded, Bluetooth implements frequency hopping spread spectrum (FHSS) to transmit data and voice (Minoli 309). FHSS minimizes transmission errors, interferences and also provides a considerable level of transmission security. Bluetooth is also capable of radio link power control which allows devices to regulate their radio power according to the desired signal levels as measured. Basic components making up Bluetooth wireless specification There are many components that make up a Bluetooth wireless specification, some of the fundamental components of this wireless specification is as elaborated below. The host- hosts can be a variety of devices but they are mainly computers and laptops that are specifically responsible for the higher levels of the Bluetooth stack architecture which includes; the Logical Link Control and Adaptation Protocol (L2CAP) and the Service Directory Protocol (SDP). The host controller – this can also be a variety of devices such as Bluetooth dongle, the host controller is mainly responsible for the management of the lower levels such as the RF-Baseband and the Link Manager Protocol (LMP). The Host Controller Interface (HCI) - this is an interface which is essentially manages the link between the host and the host controller. It is also important to note that there are devices that integrate the host and the host controller in the same device; examples of such devices are Bluetooth handset. The Radio link and the Baseband are also imperative components of the Bluetooth because the baseband layer allows the physical RF link between two units in a piconet. The baseband layer is especially responsible for maintaining formatting and addressing of packets. The two types of baseband layers are Synchronous Connection Oriented (SCO) and Asynchronous Connectionless (ACL) (Bagad 21). Benefits of Bluetooth wireless Convenience Bluetooth devices create convenience as it eliminates the need of cables to connect devices such as mobile phones and notebooks. This is specifically important in a business trip as the traveller worries less about the cables since a wireless synchronization can be enhanced via Bluetooth technology. Most importantly a Bluetooth user can easily create a connection to the internet without using any cable because the Bluetooth standard allows for internet connection via Bluetooth. Interoperability Bluetooth technology enables communication between devices from different manufacturers and hence enabling interoperability. The Bluetooth specification version 1.1 enhances interoperability through; minimizing number of options, restricting scope of parameters, adding number of clarifications and supporting a number of profile enhancements (Reddi 21). Reliability The reliability of the protocol is enhanced through three major techniques implemented by the Bluetooth technology. These techniques are Received Signal Indicator, Error Correction and Frequency-hopping Code Division Multiple Access (FH-CDMA). FH-CDMA mitigated interference within the Bluetooth network, Error Correction ensures usability of the data by use of Forward Error Correction (FEC). RSSI reduces power consumption by validation of the required amount of power to be used in the communication process (Reddi 21). Speed Bluetooth technology allows for transmissions up to 1 Mbps and can also handle up to three voice channels at the same time. The asynchronous channel is capable of a maximum of 723.2 kbps (Reddi 22). The transmission of the voice and data is of high quality and can also function in a noisy environment and still maintain an audible voice service. Power Bluetooth is capable of limiting the radio transmitter’s power output as required by the connection. The Bluetooth receiver with the aid of RSSI is capable of determining the power to be utilized by the transmitter. The information provided helps in the determination of the amount of power to be consumed by the connection and hence mitigating unnecessary power consumption (Reddi 23). Security Bluetooth provides a wireless solution between two devices; it provides secure data and voice transmission, encryption, authentication and security of the data or voice transmission. The authentication process eliminates intrusion of the data being transferred. Encryption of the data carried over the air helps in preventing eaves- droppings since decryption of the data requires a defined key. Frequency Hopped Spread Spectrum helps to further mitigate eaves-dropping (Reddi 22). Block diagram of Bluetooth showing core system architecture and their functions The functions of the major parts as shown in the block diagram above are as follows; The Radio Frequency (RF) - This section provides digital signal processing channel of the system which is the processed by the baseband section. The baseband is thus the section where a piconet Bluetooth can be established, a piconet is formed when two devices are connected together via Bluetooth. In a piconet connection orientation one device acts as a slave while the other one acts as a master. The Link Manager Protocol- This is located at the top of the link controller and this responsible for authentication, configuration of the link and also performs other minor low level protocols. The baseband and the link manager jointly form connection to the network. The Host Controller Interface (HCI) - This section or interface is responsible for the initiating communication between the host and the host controller. Fundamentally it initiates communication between the lower-layer protocols with the host device like a mobile phone or a computer. This host usually contains a processor L2CAP which can support the upper layer protocol and thus enables communication between the upper and the lower layers. In essence the upper layer consists of protocols that have service specific applications that should be integrated into the host application. Notably the radio communication protocol RFCOMM allows emulation of the serial ports over the L2CAP (Noergaard 56). Logical Link Control and Adaptation protocol (L2CAP) - This layer provides connection-oreinted and connectionless data connection services to the upper layers. It provides multiplexing, segmentation and reassembly of data packets above the predetermined size for transmission (Harte 21). The Quality of Service (QoS) is enhanced via the Bluetooth connection and thus allowing smooth exchange of information. The Group abstraction in the L2CAP allows for mapping groups in the piconet connection. Service Discovery Protocol (SDP) - This protocol provides for the means in which Bluetooth application can discover the characteristics and the services that are available and unique for Bluetooth. The device manger is responsible for the connection management and provision of inquiry services (Harte 21). RFCOMM- This section is responsible for the emulation of the RS-232 serial port which is essentially important for the transfer and management of data signals over the Bluetooth devices. It also provides transportation capabilities for the upper level services like the Object Exchange Protocol (OBEX) (Da 81). Concept, configuration and operation of a piconet used with Bluetooth wireless devices A network of Bluetooth devices is called a piconet, a piconet can have a minimum of two devices and a maximum of eight devices. It is thus possible to connect a device containing Bluetooth devices together and create a Bluetooth network or rather a piconet. In order to have a piconet, there has to be a slave and a master device. It is thus mandatory to configure one device as a master and the others as a slave. A piconet usually contains one master and several slaves. A piconet can also be configured to create what is called a scatternet, this is done by setting one master devices that coordinates several masters (Kumar 29). This means that one device which is a master in a piconet thus becomes a slave in a scatternet. The routing capabilities which are supported by Bluetooth network allows for changing network topologies of both piconet and scatternets and thus allowing for the control of data between the devices in the network. Bluetooth technology also supports both circuit switching and packet switching technologies (Scarfone 4). Packet switching in Bluetooth technology allows devices to route multiple packets over the same channel and thus saving on resource usage which then enables maintenance of data flow in the scatternet. The data rate transfer in a Bluetooth network is about 1 megabyte per second; the actual data rate is about 432 Kilo-bytes per second. A piconet offers a secure connection up to 128-bit public/ private key authentication. A 0 dBm radio offers a connection of 10 metres while a +20 dBm offers a radio link of up to 100 metres. The figure1 below shows a Bluetooth network which creates a piconet and a scatternet. Figure 1(Scarfone 4) References Da, Vinu and Thomas, Gylson. Information Technology and Mobile Communication: International Conference, AIM 2011. New York: Wiley, 2011. 80-93. Harte, Lawrence. Introduction to Bluetooth, Technology, Market, Operation, Profiles, and Services. Michigan: Althos, 2004. 1-34. Kumar, Bala and Kline, Paul J. Bluetooth application programming with the Java APIs. London: Morgan Kaufmann, 2004. 29-40. Minoli, Daniel. Telecommunications technology handbook. Johnstown, PA: Artech House, 2003. 307-310. Noergaard, Tammy. Embedded systems architecture: a comprehensive guide for engineers and programmers. New York: Newnes, 2005. 54-60. Reddi, Prathap. Bluetooth Technology and Its Applications with JAVA and J2ME. PHI Learning Pvt. Ltd., 2006. 20-29. Bagad, V.S and Dhotre, I.A. Computer Communication Networks. Technical Publications, 2009. 20-25 Scarfone, Karen. Guide to Bluetooth Security: Recommendations of the National Institute of Standards and Technology. New York: DIANE Publishing, 2009. 2-10. Read More