Short-Range Radio Frequency NetworkingPurposeIntroductionFigure 3.18 A typical NAT-based home networkFigure 3.22 IEEE 802 network standardsDetailsRadio technologyProtocol StackBluetooth Protocol StackTypical application ScenariosApplication activitiesDiscoveryBluetooth clientsService/device discoveryService discovery (contd.)Serial PortSerial Port Profile (SPP)Interoperable ProfilesProfilesHow does it work? Bluetooth frame structureServer operationClient operationUses of Bluetooth01/14/19 1Short-Range Radio Frequency NetworkingB. Ramamuthy01/14/19 2PurposeStudy personal area network PAN and related standard in bluetoothBased on java.sun.com Bluetooth API overview, design and development.Other sources: Colouris text and palo wireless bluetooth resource center.Bluetooth.com source:01/14/19 3IntroductionBluetooth is protocol for short range, frequency hopping radio link between devices.Devices such as phones, PDAs, medical devices that are bluetooth-enabled.Based on Industrial, Scientific and Medical (ISM) frequency band.Unlicensed and globally available.Originally from Ericsson; bluetooth named after a Nordic king instrumental in integration of Scandinavian countries.01/14/19 4Figure 3.18 A typical NAT-based home network 83.215.152.95Ethernet switc hModem / firewall / router (NAT enabled)printerDS L or Cableconnec tion to IS P192.168.1.xx subnetPC 1WiFi base station/access point 192.168.1.10192.168.1.5192.168.1.2192.168.1.1192.168.1.104PC 2192.168.1.101Laptop192.168.1.105Game box192.168.1.106Media hubTV monitorBluetoothadapterBluetoothprinterCamera01/14/19 5Figure 3.22IEEE 802 network standardsIEEE No. Name Title Reference802.3 Ethernet CSMA/CD Networks (Ethernet) [IEEE 1985a]802.4 Token Bus Networks [IEEE 1985b]802.5 Token Ring Networks [IEEE 1985c]802.6 Metropolitan Area Networks [IEEE 1994]802.11 WiFi Wireless Local Area Networks [IEEE 1999]802.15.1 Bluetooth Wireless Personal Area Networks [IEEE 2002]802.15.4 ZigBee Wireless Sensor Networks [IEEE 2003]802.16 WiMAX Wireless Metropolitan Area Networks[IEEE 2004a]01/14/19 6DetailsRadio technologyProtocol stackInteroperable profilesHow does the technology work?How is the technology used?Sample APIs to work with bluetooth:javax.bluetooth; javax.obex (for object exchange)01/14/19 7Radio technology2.5Ghz ISM bandThe bluetooth devices in a proximity form a piconet comprising a master and upto 7 devices.Piconets can connect, the master in a piconet can provide a bridge.Global and unlicensed.01/14/19 8Protocol StackProtocol stack provides a number of higher level APIs for service discovery and serial IO simulation, lower-level protocols for packet segmentation and reassembly, protocol multiplexing and QoS01/14/19 9Bluetooth Protocol StackBluetooth RadioBaseband Link Controller (LC)Link Manager protocol (LMP)Host Controller Interface FirmwareBluetooth Host ControllerFirmware + HardwareHost controller interface (HCI)Logical link control & Adaptation Protocol (L2CAP)RFCOMM (serial port emulation)OBEXWAPUDP/TCPIPPPPService discovery protocol (SDP)Bluetooth HostController Stack(software)Java API for Bluetooth wireless technology (JSR-082)Application01/14/19 10Typical application ScenariosBluetooth application can be either server or clientPeer-peer exposing both client and server functionalityApplication need not be in JavaHowever J2ME-based devices can avail of the bluetooth API.Though we discuss Java-based API here, MS Vista has a WS based API for devices.01/14/19 11Application activitiesjava.sun.comBluetooth intro01/14/19 12Discovery01/14/19 13Bluetooth clientsDiscoveryAgent support discovery of services and devices.Clients wanting to be notified should implement and register Discovery Listener interface.01/14/19 14Service/device discoveryA similar sequence can be assumed for device Discovery.Services have a UUIDThere is LocalDeviceAnd RemoteDevice APIs to control the devices.01/14/19 15Service discovery (contd.)Once the local device has discovered at least one remote device, it can begin to search for available services – Bluetooth applications it can use to accomplish useful tasks. Because service discovery is much like device discovery, DiscoveryAgent also provides methods to discover services on a Bluetooth server device, and to initiate service-discovery transactions01/14/19 16Serial PortThe RFCOMM protocol, which is layered over the L2CAP protocol, emulates an RS-232 serial connection. The Serial Port Profile (SPP) eases communication between Bluetooth devices by providing a stream-based interface to the RFCOMM protocol. Some capabilities and limitations to note: Two devices can share only one RFCOMM session at a time. Up to 60 logical serial connections can be multiplexed over this session. A single Bluetooth device can have at most 30 active RFCOMM services. A device can support only one client connection to any given service at a time.Serial Port Profile (SPP)01/14/19 1701/14/19 18Interoperable ProfilesProfiles have been developed to manage cross-platform interoperability among different manufacturer’s products. They describe how implementations of user models have to be accomplished.Lets examine the bluetooth profile as provided by palowireless.01/14/19 19Profiles01/14/19 20How does it work?Bluetooth frame structureSCO packets (e.g. for voice data) have a 240-bit payload containing 80 bits of data triplicated, filling exactly one timeslot.bits: 72 18 18 18 0 - 2744 Access code Headercopy 1Headercopy 2Headercopy 3Data for transmissionbits: 3 1 1 1 4 8Destination Flow Ack Seq Type Header checksumAddress withinPiconet= ACL, SCO,poll, nullHeader01/14/19 21Server operationConstruct a URL that indicates how to connect to the service, and store it in the service record Make the service record available to the client Accept a connection from the client Send and receive data to and from the client The URL placed in the service record may look something like: btspp://102030405060740A1B1C1D1E100:501/14/19 22Client operationTo set up an RFCOMM connection to a server the client must: Initiate a service discovery to retrieve the service record Construct a connection URL using the service record Open a connection to the server Send and receive data to and from the server01/14/19 23Uses of BluetoothSome are from Accenture:Wiring the wiredLocating lost itemsActivity