Bluetooth A cable replacement technology 1 Mbs symbol
Bluetooth � � A cable replacement technology 1 Mb/s symbol rate Range 10+ meters Single chip radio � at low power & low price point 1
Value proposition of Bluetooth Cordless headset mouse Cell phone Cable replacement Data access point Internet access Ad hoc networking 2
Bluetooth Overview � ISM band divided into 79 freq. channels: � 2. 402 - 2. 480 GHz of 1 MHz each � FHSS: 1600 hops/sec � Reduces interference Cordless Baby monitors LANs Bluetooth 802. 11 g, b Microwave oven Unused 802. 11 a Channel divided into 625 µs time slots � 1 Mb/s rate, 10+ meter range � Point to Multipoint � � Master to slave communication Service discovery mechanism � Native support for voice (Time Division Duplex scheme) � 3
Class Maximum Permitted Power m. W (d. Bm) Range (m) Class 1 Class 2 100 m. W (20 d. Bm) 2. 5 m. W (4 d. Bm) ~100 ~10 Class 3 1 m. W (0 d. Bm) ~1 Version Data Rate Version 1. 2 IEEE Standard 802. 15. 1 -2005 1 Mbit/s Version 2. 0 + EDR (Enhanced Data Rate) (November 10, 2004) 3 Mbit/s Version 3. 0 + HS (High Speed) (April 21, 2009) Version 4. 0 (Bluetooth Low Energy (BLE)) 24 Mbit/s 200 kbit/s ~ 4
Bluetooth Radio • Radio specification Goal is a single chip radio Relaxed RF specifications reduce cost • 2. 4 GHz ISM band radio Frequency Hop Spread Spectrum (FHSS) : 1600 hops/sec 5
Bluetooth Radio Bluetooth is a 2. 4 GHz ISM band spread spectrum radio – 2400 - 2483. 5 MHz allows world wide (almost) operation – 1600 hops/sec (625 msec) frequency hopper – 79 One MHz channels (23 in France, Japan) – Tx power 1 m. W – Range 10 cm to 10 m at low power – Data rates: from 432/432 kbps symmetric channel to 723/57 kbps asymmetric channel 6
BT Topology Scatternet Piconets Master / Slave Piconet Scatter. Net Bluetooth Piconet and Scatternet formation 7
Master/Slave Piconet • One unit becomes the master and the others Slaves with maximum of 8 devices in a piconet. • Master/slave relationship establishes timing • A slave can become a master in another Piconet. This connects two Piconets into a Scatter Net MASTER 8
Bluetooth Pico and Scatter nets • Master in one piconet can be a slave in another • Addressing limits number of active devices in a piconet to 7 • An indefinite number of parked devices remain synchronized with the piconet but are not active 9
Scatter net 10
Scatter net scenario 2 11
Inter Piconet communication Cordless headset mouse Cordless headset Cell phone 12
Connection Setup � Inquiry - scan protocol � to learn about the clock offset and device address of other nodes in proximity 13
Piconet formation � Page - scan protocol � to establish links with nodes in proximity Master Active Slave Parked Slave Standby 14
Bluetooth Connection States Link Manager Controls BT operational modes – Active Mode • BT can accommodate only 7 active slaves • AM_ADDR: 3 bit address given to each active slave – Hold Mode – Park Mode – Sniff Mode 15
Bluetooth Addressing � BT device address (BD_ADDR) � 48 -bit � IEEE MAC address 3 -bit active member address (AM_ADDR) � Maximum 8 active members in a piconet � All zero broadcast address � 8 -bit parked member address (PM_ADDR) � 255 � parked members 3 low power modes � Sniff : Reduced listening, Keeps AMA, communication during specified Sniff time slots � Hold : Keeps AMA, Do other things or sleep � Park : Release AMA, Gets PMA, Keeps synced to piconet 16
The Protocol Stack 17
Bluetooth Protocol Stack Simplified protocol architecture High Level Applications Standards Adaptation APIs Adaptation RFCOMM, BNEP Host Application(s) AT UDP TCP Legacy OBEX IP Commands APIs Host (PC, …) L 2 CAP Logical link control for each separate connection Performs Segmentation, Reassembly of packets Multiplexing of High Level Applications, Qo. S HCI Core Link Manager Handles physical Link Setup and Control Baseband Low level processing of packets. Inquiry and page scan Active, Hold, Sniff, Park state management, Freq. Hop calculation Host Controller (BT Module) Radio 18
BT Profile Each Bluetooth device supports one or more profiles � A profile represents a default solution for a usage model � Vertical slice through the protocol stack � Basis for interoperability between devices from different vendors � Profile List � Generic Access Profile � Service Discovery Application Profile � Cordless Telephony Profile � Intercom � Serial Port Profile � Headset Profile � Dial-up Networking Profile � Fax Profile � LAN Access Profile � Generic Object Exchange Profile � Object Push Profile � File Transfer Profile � Synchronization Profile � And more coming 19
Bluetooth Profiles 20
Bluetooth Profile Specifications Publish Date Hands-Free Profile 1. 5 (HFP 1. 5) 25 -Nov-05 Advanced Audio Distribution Profile 1. 2 16 -Apr-07 Hardcopy Cable Replacement Profile (HCRP) 1. 2 27 -Apr-06 Advanced Audio Distribution Profile 1. 0 4 -Jun-03 Hardcopy Cable Replacement Profile (HCRP) 1. 0 23 -Sep-02 Audio/Video Remote Control Profile 1. 4 26 -Jun-08 Headset Profile (HSP) 1. 2 18 -Dec-08 Audio/Video Remote Control Profile 1. 3 16 -Apr-07 Headset Profile (HSP) 1. 1 22 -Feb-01 Audio/Video Remote Control Profile 1. 0 4 -Jun-03 Health Device Profile (HDP) 26 -Jun-08 Basic Imaging Profile (BIP) 25 -Jul-03 Human Interface Device Profile (HID) 24 -May-03 Basic Printing Profile (BPP) 1. 2 27 -Apr-06 Intercom Profile (ICP) 22 -Feb-01 Basic Printing Profile (BPP) 1. 0 10 -Feb-04 Message Access Profile (MAP) 4 -Jun-09 Cordless Telephony Profile (CTP) 22 -Feb-01 Object Push Profile (OPP) 22 -Feb-01 Device Identification Profile (DI) 1. 3 26 -Jul-07 Personal Area Networking Profile (PAN) 20 -Feb-03 Device Identification Profile (DI) 1. 2 27 -Apr-06 Phone Book Access Profile (PBAP) 27 -Apr-06 Dial-Up Networking Profile (DUN) 22 -Feb-01 Serial Port Profile (SPP) 22 -Feb-01 Fax Profile (FAX) 22 -Feb-01 Service Discovery Application Profile 22 -Feb-01 File Transfer Profile (FTP) 22 -Feb-01 SIM Access Profile (SAP) 1. 1 18 -Dec-08 Generic Audio/Video Distribution Profile 1. 2 16 -Apr-07 SIM Access Profile (SAP) 1. 0 12 -May-05 Generic Audio/Video Distribution Profile 1. 0 24 -May-03 Synchronization Profile (SYNC) 22 -Feb-01 Generic Object Exchange Profile (GOEP) 22 -Feb-01 Video Distribution Profile (VDP) 8 -Sep-04 21
Protocol Stack & Profiles Protocol Stack with profiles Simplified protocol stack 22
IP over Bluetooth v 1. 0 Applications SDP IP RFCOMM Data Audio L 2 CAP Link Manager Baseband RF GOALS Internet access using cell phones � Connect PDA devices & laptop computers to the Internet via LAN access points � 23
Bluetooth v 1. 1 Bluetooth Network Encapsulation Protocol (BNEP) 24
IP over Bluetooth Quick Solution: Use PPP over Virtual Serial Link 25
Current: Bluetooth PAN � Test bed: Private IP Network over Bluetooth eth 0 Linux Kernel 2. 4. 20 Blue. Z Bluetooth Stack 802. 1 d Ethernet Bridge bnep 0: 0. 0 bnep 1: 0. 0 master 1 br 0: 10. 0. 0. 1 bnep 0: 10. 0. 0. 2 slave 1 Socket Bluetooth Compact. Flash Cards D-Link DBT 120 USB Dongles bnep 0: 10. 0. 0. 3 slave 2 26
References � � � Bluetooth core specification v 1. 1 Bluetooth BNEP profile specification Dynamic Location Discovery in Ad-Hoc Networks: http: //nesl. ee. ucla. edu/projects/ahlos/reports. htm Blue. Z Bluetooth stack: http: //bluez. sourceforge. net Tutorial: Bluetooth Vs. 802. 11 http: //www. winlab. rutgers. edu/~pravin/publications/papers/T 3 -Bluetooth. zip Location Based Services: https: //doc. telin. nl/dscgi/ds. py/Get/File-23319/location_based_services. pdf 27
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