network protocols handbook.pdf

214Protocols GuideLAN - Wilress LAN ProtocolsProtocol NameIEEE 802.15 and Bluetooth:WPAN CommunicationsProtocol DescriptionIEEE 802.15, a standardization of Bluetooth wireless specificationdefined by IEEE, is for wireless personal area networks(WPANs). IEEE 802.15 has characters such as short-range, lowpower, low cost, small networks and communication of deviceswithin a Personal Operating Space.The initial version, 802.15.1, was adapted from the Bluetoothspecification and is fully compatible with Bluetooth 1.1. Bluetoothbecomes widely used specification for wireless communicationsamong portable digital devices including notebook computers,peripherals, cellular telephones, beepers, and consumerelectronic devices. The specification also allows for connectionto the Internet. 802.15.1/Bluetooth specify standards in on thePhysical layer and Data link layer of the OSI model with the followingfour sub-layers:RF layer: The air interface is based on antenna power rangestarting from 0 dBm up to 20 dBm. Bluetooth operates in the 2.4GHz band and the link range is anywhere from 10 centimetersto 10 meters.Baseband layer: establishes the Bluetooth physical link betweendevices forming a piconet -- a network of devices connected inan ad hoc fashion using Bluetooth technology.Link manager: sets up the link between Bluetooth devices. Otherfunctions of the link manager include security, negotiation ofBaseband packet sizes, power mode and duty cycle control ofthe Bluetooth device, and the connection states of a Bluetoothdevice in a piconet.Logical Link Control and Adaptation Protocol (L2CAP): providesthe upper layer protocols with connectionless and connectionorientedservices.The IEEE 802.15 Working Groups are making progress to improvethe Bluetooth standards. They proposed two general categoriesof 802.15: the low rate 802.15.4 (TG4) and high rate802.15.3 (TG3). The TG4 version provides data speeds of 20Kbps or 250 Kbps, low power and low cost solutions. The TG3version supports data speeds ranging 20 Mbps or greater, formulti-media applications.IEEE 802.15/Bluetooth, IEEE 802.11/WLAN and IEEE 802.16/WiMAX technologies are complementary to each other andeach play a unique role in today’s wireless communications. Thefollowing table outlines the three technologies:Parameters8 0 2 . 1 6 a(WiMAX)8 0 2 . 1 1(WLAN)802.15 (Bluetooth)F r e q u e n c y 2-11GHz 2.4GHz VariesBand:Range ~31 miles ~100 meters ~10metersData transferrate:Numberusers:ofRelated Terms:70 Mbps 11 Mbps – 55Mbps20Kbps – 55MbpsThousands Dozens DozensWLAN, WMAN, WiMAX, IEEE 802.11, IEEE 802.16765ApplicationPersentationSessionReference Links:http://standards.ieee.org/getieee802/802.15.htmlIEEE 802.15 Specification Download Page4321TransportNetworkData LinkPhysicalLogical Link Control(LLC)Medium Access Layer(MAC)Physical Control(PHY)ApplicationsOthers TCP/IP RFCOMM SDPL2CAPLink ManagerBasebandRFAudioISO OSI ModelLayersIEEE 802 Standards IEEE 802.15.1Bluebooth WPANFigure 2-14: IEEE 802.15 (Bluetooth) Protocol Stack