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Bluetooth Wireless System Joe Decuir Microsoft Chair, Seattle COM-19 [email protected] Agenda Wireless Overview (from Tim Moore of Microsoft) Bluetooth System Overview (from Jim Kardach of Intel) Windows Bluetooth Stack (from Ken Ray and Stan Adermann of Microsoft) References: http://www.microsoft.com/winhec Windows Wireless Architecture Tim Moore Lead Program Manager Windows Networking Microsoft Corporation Wireless Overview Agenda Wireless trends WAN, LAN, PAN Scenarios Adhoc, home, small business Enterprise, ISP Wireless Trends IP networks Always connected Increased bandwidth Convenience Moving from vertical market to horizontal markets Moving from proprietary to standards based Proliferation of smart devices New scenarios enabled Outsourcing Adhoc networks Information Anytime, Anywhere Connecting Everything Windows 98 Windows 2000 Desktop Windows NT Embedded Windows CE Intelligent appliance Micro-browser Services Servers Smart object Smart Card for Windows Wide-Area Wireless Wide Area Wireless US Summary 1999 Q1 Q2 Q3 2000 Q4 Q1 Q2 Q3 2001 Q4 Q1 Q2 Q3 2002 Q4 Q1 Q2 Q3 2003 Q4 Q1 Q2 Q3 Q4 Mobitex 8, DataTAC 19.2 Packet CDPD 19.2 Packet GSM 9.6 Circuit-Switched iDEN - Nextel - 9.6 Packet and Circuit-Switched cdmaOne Circuit-Switched 14.4 - IS-95A General Deployment Trials Start General Deployment Trials AirTouch GTE, Sprint Limited Deployment cdma2000 1XRTT 153 Kbps - Packet Trials Start GSM GPRS Technologies Trials Start General Deployment 19.2 Rx/9.6 Tx 57.6 Kbps 38.4 Rx/9.6 Tx EDGE 384 Kbps Packet Limited Deployment Trials Start General Deployment Materials from Andrew Seybold-Microsoft Exchange Conference 1999 Local-Area Wireless Local Area Network Technology 1999 Q1 Q2 Q3 2000 Q4 Q1 Q2 Q3 2001 Q4 Q1 Q2 Q3 2002 Q4 Q1 Q2 Q3 2003 Q4 Q1 Q2 Q3 Q4 802.11 (FHSS) 2.4 GHz 1 Mbps Freq. Hopped Spread Spectrum 802.11 (DSSS) 2.4 GHz 1 or 2 Mbps Direct Sequence Spread Spectrum Hiperlan 23.5 Mbps High Performance Radio LAN Initial Shipments P802.11b (DSSS) 2.4 GHz Initial 11 Mbps Shipments Direct Sequence Spread Spectrum Final Specification P802.11a 5 GHz Specifications 54 Mbps Approved Direct Sequence Spread Spectrum Initial Mobile Shipments Materials from Andrew Seybold-Microsoft Exchange Conference 1999 Personal Area Wireless Local Area Network Technology 1999 Q1 Q2 Q3 2000 Q4 Q1 Q2 Q3 2001 Q4 Q1 Q2 Q3 2002 Q4 Q1 Q2 Q3 2003 Q4 Q1 Q2 Q3 Q4 IrDA 4Mbps Bluetooth 721 Kbps Computer Integrated Products Initial Shipments Integrated Handsets PC Card and CF Module Materials from Andrew Seybold-Microsoft Exchange Conference 1999 Ad Hoc Networks Many diverse devices to be connected Desktops, Notebooks TVs, games Books, tablets, handheld PCs Phones, Pagers PC companions A Connected Home 1394 STB IrDA 802.11 Ethernet/1394b Internet Bluetooth PLC xDSL Cable Satellite POTS, ISDN Residential Gateway Phone A Connected Small Office Phone Internet T1, T3, … Small Business Server Ethernet Edge Server 802.11 Bluetooth Enterprise GPRS GPRS IrDA Information at your fingertips GPRS At meetings, in the office, on the road Reliable, secure, multimedia LAN Bluetooth Internet Web Server 802.11 T1, T3, … Ethernet Proxy Server An ISP Connected Public Space Bluetooth Phone GPRS Discovery of proximity services (flight schedules at airport, mall directories, …) IrDA Internet Web Server 802.11 T1, T3, … Ethernet Proxy Server Wireless Architecture “Just works” Always connected Unified transport: IP Mobility Unified security model Adhoc QoS Performance Wireless Architecture WinSock 2.0 TAPI 3.0 Routing APIs Dial-up Networking APIs Network streaming (DirectX) Networking APIs Network Location 802.1X DNS DHCP Networking Services RSVP UPnP NetBT IP packet filtering IP forwarder TCP/IP Route table Protocol stacks Packet classifier Packet scheduler NDIS WAN PPTP IGMP NDIS 5.1 Ethernet Async Bluetooth IRDP RNDIS TR 802.1D 802.11 Affected by Wireless Just Works No configuration CDPD Especially when roaming Configure Network Equipment Identifier 802.11 Configure network name and security keys Per location Bluetooth Configure PIN numbers Per device Adhoc Architecture FTP OBEX WinSock 2.0 Networking Services 802.1X RSVP UPnP Network EAP-TLS DHCP Location Netbt IrDA Protocol stacks TCP/IP RFCOMM NDIS 5.1 802.1D BthNet IrDA Bluetooth 802.11 1394 Ethernet What is an adhoc network? No network infrastructure at all Interconnections not managed Multiple interconnections to destinations Loops in the network Home network E.g. back to back Ethernet APIPA when no DHCP server NetBT broadcast for adhoc name resolution ICS contains DNS proxy and DDNS support for the adhoc home network Service Discovery Protocols SSDP protocol enables UPnP discovery SDP protocol enables Bluetooth wireless technology discovery IrLAP protocol enables IrDA discovery IrDA/Bluetooth Architecture FTP Winsock IrTRAN-P Print server monitor IrOb NDISWAN IrDial TinyTP NDIS OBEX Unimodem IPOb BthOb UPnP IrCOMM IrLMP IrLAP IrLPT TCP/IP IrSIR SERIAL IrDA hardware RFComm HID KsMixer 802.1D BthNet FIR driver Hardware BthMDM BthUSB USBD BtHID BtAudio BthPORT BthPCCARD PCMCIA BT hardware IrDA Applications File transfer Integrated into shell Image exchange from camera Dial-up networking via cellphone Printing Synchronization ActiveSync® Bluetooth Applications Subset of IrDA File transfer Integrated into IrDA ftp transfer Dial-up Networking via cellphone IR and Bluetooth applications are tied to particular media Do not inter-operate Bluetooth Architecture Overview Andrew Liu Technical Marketing Manager Intel Architecture Labs Intel Corporation "The Bluetooth Specification is still preliminary; All information regarding Bluetooth is subject to change without notice" Agenda Bluetooth SIG update Bluetooth architectural overview Summary/call to action What Does Bluetooth Wireless Technology Do For You? Landline Cable Replacement Data/Voice Access Points Personal Ad-hoc Networks Program Update Final specification published Monday 7/26/99 Bluetooth membership exceeds 1,800 companies! Core technology specs and Profile requirements Result of work from ~200 engineers Bluetooth wireless technology becoming the choice for wireless connectivity Full list of member companies on Web site www.bluetooth.com Bluetooth program on track for products available in 2000 Products available this year Next step is qualification program SIG now focusing on ensuring product interoperability Bluetooth qualification program started Bluetooth wireless technology is the basis for the IEEE 802.15.1 standard Bluetooth SIG has expanded New contracts and membership types The SIG Formally Known As Bluetooth ; ) New Contracts Adopter/Early Adopter = Early Adopter Early Adopter in working group = Associate Early Adopter Contract, Associate Amendment Open IP license to Bluetooth wireless technology Early Adopter Contract Original “Foundation Specifications” New technology in and around the 12 specification working groups Only need to sign 1 contract to use any Bluetooth wireless technology (the new one) Bluetooth Momentum 1600 SIG Expands 1400 Byte.com Award 1200 1.0 Spec Release 1000 Adopters Conferences Discover Awards Total 800 #/Mon 600 400 200 SIG Formed 0 A-98 M-98 ® R R J-98 J-98 A-98 S-98 O-98 N-98 D-98 J-99 F-99 M-99 A-99 M-99 SIG is still growing J-99 J-99 A-99 S-99 O-99 N-99 D-99 J-00 F-00 Future Directions for Bluetooth I. II. III. IV. V. VIII. IX. X. XI. XII. XIII. XIV. ® R R Bluetooth Second Generation Radio Bluetooth Personal Area Networking Bluetooth in and around the Car Bluetooth “Wake-up” Bluetooth Human Interface Devices (HID) Bluetooth Audio/Visual Bluetooth ISM interference/Interoperability Bluetooth Printing Bluetooth Still Image Bluetooth Extended Service Discovery Protocols Bluetooth Local Positioning Bluetooth UDI What is Bluetooth? Applications TCP/IP HID RFCOMM Application Framework and Support Data Host Controller Interface L2CAP Audio Link Manager Baseband Link Manager and L2CAP LMP Radio & Baseband RF A hardware description An application framework Latest Version on Bluetooth Website: www.Bluetooth.com What is Bluetooth? Software Applications TCP/IP HID RFCOMM Data L2CAP Audio Link Manager LMP Baseband RF A hardware description An application framework Modules Testing to Specification T e c h n o l o g y Certification T e c h n o l o g y Applications TCP/IP HID vCard vCal RFCOMM vCard Data IrOBEX vCal PPP IrOBEX PPP Audio TS0710 Ctrl L2CAPAudio Audio A Ctrl U D I O A U D I O TS0710 Link Manager Baseband RF Application Framework Application Layer Framework Certification Certification Certification Classes UDP WAP WAP TCP/IP L2CAP TCP/IP LM L2CAP BB LM RF BB RF Lower Interface Application Framework Certification Class Class BT.OBEX Layer Certification Classes BT.vCard BT.OBEX BT.vCal Service UDP Still Img Still Img HID HID LMP vCard vCal UDP Service PPP IrOBEX vCard WAP vCalImages Still UDP PPP Ctrl Audio IrOBEX RFCOMM WAP TCP/IP Still Images HID Audio Ctrl RFCOMM TCP/IP HID Type IrOBEX IrOBEX PPP RFCOMM Type RFCOMM IrOBEX TCP/IP IrOBEX HID PPP RFCOMM L2CAP RFCOMM L2CAP TCP/IP L2CAP 2 L HID CAP 2 L CAP 2 L CAP L2CAP L2CAP BT.PPP Lower Interface BT.TS0710 Class BT.TS0710 BT.OBEX BT.TCP/IP BT.OBEX BT.HID BT.PPP 2 BT.TS0710 BT.L CAP-A 2 BT.TS0710 BT.L CAP-D 2 BT.TCP/IP BT.L CAP-D 2 BT.HID BT.L CAP-D 2 BT.L CAP-A 2 BT.L CAP-D BT.L2CAP-D BT.L2CAP-D BT.UDP Certification BT.PPPClass BT.OBEX BT.vCard BT.WAP BT.vCal BT.SImg BT.UDP BT.PPP BT.AudioCtrl BT.OBEX BT.TS0710 BT.WAP BT.TCP/IP BT.SImg BT.HID BT.AudioCtrl BT.TS0710 BT.TCP/IP BT.HID Basic Layer Certification Classes Lower Interface Class Audio Data 2 L CAP LM BT.LM-A BT.LM-D LM BB BT.BB-A BT.BB-D Lower Interface Service BB RF BT.RF BT.RF Type Class RF Air Audio Data A unit that supports both audio and data gets the certification class A and D. 2 Example: BT.BB-A,D L CAP LM BT.LM-A BT.LM-D LM BB BT.BB-A BT.BB-D BB RF BT.RF BT.RF RF Air - Service Certification Class Basic Layer Certification Audio Basic Layer Certification Classes Type Data 2 2 BT.L CAP-A BT.L CAP-D BT.LM-A BT.LM-D Certification Class BT.BB-A BT.BB-D BT.RF BT.RF Audio Data 2 2 BT.L CAP-A BT.L CAP-D BT.LM-A BT.LM-D BT.BB-A BT.BB-D BT.RF BT.RF A unit that supports both audio and data gets the certification class A and D. Example: BT.BB-A,D Bluetooth devices will be tested against the specification Bluetooth Qualified Test Facilities (BQTF) What does Bluetooth Do? Topology Supports up to 7 simultaneous links Flexibility Data rate Goes through walls, bodies, cloths... Line of sight or modified environment 1 MSPS, 720 Kbps Varies with use and cost Power 0.1 watts active power 0.05 watts active power or higher Size/Weight 25 mm x 13 mm x 2 mm, several grams Cost Long-term $5 per endpoint Size is equal to range. Typically 1-2 meters. Weight varies with length (ounces to pounds) ~ $3-$100/meter (end user cost) Range 10 meters or less Up to 100 meters with PA Intended to work anywhere in the world Range equal to size. Typically 1-2 meters Cables vary with local customs Very, link layer security, SS radio Secure (its a cable) Universal Security Cable Replacement Each link requires another cable Who is Bluetooth? Harald Blaatand “Bluetooth” II King of Denmark 940-981 Son of Gorm the Old (1st King of Denmark) and Thyra Danebod (daughter of King Ethelred of England) This is one of two Runic stones erected in his capitol city of Jelling (central Jutland) This is the front of the stone depicting the chivalry of Harald. The stone’s inscription (“runes”) say: Harald christianized the Danes Harald controlled Denmark and Norway Harald thinks notebooks and cellular phones should seamlessly communicate Bluetooth RF Specifications Specified for low cost, single chip implementation Noise floor margin for substrate noise and low current LNA Linearity set by near-far problem In-band image allows low-cost low IF VCO phase noise enables integrated VCO TX-RX turn around time enables single synthesizer 2.4 ISM band chosen for global use and process capabilities Sensitivity traded for low cost integration of transceiver and baseband Basic Baseband Protocol Frame Frame fk fk+1 One Slot Packet Master One Slot Packet Slave 625 us One Slot 625 us One Slot Spread spectrum frequency hopping radio 79/23 one MHz channels Hops every packet Packets are 1, 3, or 5 slots long Frame consists of two packets fk+1 Three Slot Packet Master One Slot Packet Slave fk Transmit followed by receive Nominally hops at 1600 times a second (1 slot packets) Network Topology Radio Designation Connected radios can be master or slave Radios are symmetric (same radio can be master or slave) Piconet Master can connect to 7 simultaneous or 200+ active slaves per piconet Each piconet has maximum capacity (1 MSPS) Unique hopping pattern/ID Scatternet High capacity system Minimal impact with up to 10 piconets within range S P M sb Radios can share piconets! M P S P sb S S The Piconet IDa IDd IDa IDd IDa D A P M IDe IDe sb E IDa IDb IDb B IDc S In forming a piconet, master gives slaves its clock and device ID IDc C All devices in a piconet hop together IDa S Hopping pattern determined by device ID (48-bit) Phase in hopping pattern determined by Clock Non-piconet devices are in standby Piconet Addressing M or S Active Member Address (AMA, 3-bits) Parked Member Address (PMA, 8-bits) sb P IDa Functional Overview Standby Ttypical=2s Connecting States Page Actively on a piconet (master or slave) Ttypical=0.6s Active States Low Power connected states Transmit data AMA Connected AMA Ttypical=2 ms Park/Hold/Sniff Inquiry Connect to a specific radio Connected Ask about radios to connect to Page Standby Inquire Waiting to join a piconet Unconnected Standby Low Power States Releases AMA Address PARK PMA Ttypical=2 ms Ttypical=2 ms SNIFF AMA HOLD AMA Packet Types/Data Rates Packet Types TYPE SCO link 1 0000 0001 0010 0011 NULL POLL FHS DM1 2 0100 0101 0110 0111 1000 1001 SEGMENT Data Rates (Kbps) ACL link TYPE NULL POLL FHS DM1 DH1 HV1 HV2 HV3 DV AUX1 3 1010 1011 1100 1101 DM3 DH3 4 1110 1111 DM5 DH5 ASL –Packet like behavior SCO – Circuit like behavior symmetric asymmetric DM1 108.8 108.8 108.8 DH1 172.8 172.8 172.8 DM3 256.0 384.0 54.4 DH3 384.0 576.0 86.4 DM5 286.7 477.8 36.3 DH5 432.6 721.0 57.6 Mobile = Battery Life Low power consumption* Standby current < 0.3 mA Voice mode 8-30 mA Þ 75 hours Data mode average 5 mA (0.3-30mA, 20 kbit/s, 25%) Þ 3 months Þ 120 hours Low Power Architecture Programmable data length (else radio sleeps) Hold and Park modes 60 µA Devices connected but not participating Hold retains AMA address, Park releases AMA, gets PMA address Device can participate within 2 ms *Estimates calculated with 600 mAh battery and internal amplifier, power will vary with implementation Error Handling 72b 54b access code header Forward-error 0-2745b payload correction (FEC) headers are protected with 1/3 rate FEC and HEC payloads may be FEC protected 1/3 rate: simple bit repetition (SCO packets only) 2/3 rate: (10,15) shortened Hamming code 3/3 rate: no FEC ARQ 16-bit CRC (CRC-CCITT) & 1-bit ACK/NACK 1-bit sequence number ® R R (ACL packets only) Bluetooth Security Features Fast Frequency Hopping (79 channels) Low Transmit Power (range <= 10m) Authentication of remote device Encryption of payload data Based on link key (128 Bit) May be performed in both directions Stream cipher algorithm ( 128 Bit) Affects all traffic on a link Initialization PIN entry by user Application Level Security Builds on-top of link-level security Security levels for services Creates trusted device groups Authorization required Authentication required Encryption required Different or higher security requirements could be added: Personal authentication Higher security level Public key Application level security Builds on-top of link-level security creates Security trusted device groups levels for services authorization required authentication required encryption required Different or higher security requirements could be added: Personal ® R R Authentication Higher Security Level Public Key Bluetooth Is Global One version for the world Architecture compliant with global emission rules (2.4 GHz ISM band) Architecture compliant and safe for use on airlines Working through FCC, EC, MPT for spectrum, and power harmonization Working with FAA, JAA, FCC, airplane manufacturers, and airlines Reviewing security architecture with affected countries Bluetooth Radio Modules Complete radio on a module Designed to meet “Limited Module Compliance” (LMA) requirements Pre-certified to meet global regulatory requirements Allows devices assembled with modules to be “self-certified” USB Interface Solder-ball connections External Antennae Compact FLASH Card 25 mm dia 17x33mm 36x43mm Bluetooth Protocols Still Image WAE vCard/vCal WAP OBEX HID Service Discovery TCP/UDP Audio Printing RFCOMM IP TCS L2CAP Host Controller Interface - Bluetooth Specific - Reused Spec - Modified Bluetooth protocols Host Controller Interface (HCI) provides a common interface between the Bluetooth host and a Bluetooth module Interfaces in spec 1.0: USB; UART; RS-232 Link Layer Control & Adaptation (L2CAP) A simple data link protocol over baseband ® R R connection-oriented & connectionless protocol multiplexing segmentation & reassembly QoS flow specification per connection (channel) group abstraction Bluetooth protocols Service Discovery Protocol (SDP) Defines a service record format Defines a inquire/response protocol for discovering services ® R R Information about services provided by attributes Attributes composed of an ID (name) and a value IDs may be universally unique identifiers (UUIDs) Searching for and browsing services Bluetooth protocols RFCOMM (based on GSM TS 07.10) emulates a serial-port to support a large base of legacy (serial-port-based) applications allows multiple “ports” over a single physical channel between two devices Telephony Control Protocol Spec (TCS) call control (setup & release) group management for gateway serving multiple devices Legacy ® R R protocol reuse resuse existing protocols, e.g., IrDA’s OBEX, or WAP for interacting with applications on phones Interoperability And Profiles Represents default solution for usage model Vertical slice through the protocol stack Basis for interoperability and logo requirements Each Bluetooth device supports one or more profiles Applications Protocols Profiles Summary Bluetooth is a global, RF-based (ISM: 2.4GHz band), short-range, connectivity technology and solution for portable, personal devices It is not just a radio Create piconets on-the-fly (approximately 1Mbps) The Bluetooth spec comprises Piconets may overlap in time and space for high aggregate bandwidth A hardware and software protocol specification Usage case scenario profiles and interoperability requirements To learn more: http://www.bluetooth.com Call To Action Join the SIG if you haven't already Learn how Bluetooth wireless technology works NOW! See Microsoft's presentation on Bluetooth wireless technology Big conference in Monte Carlo - check it out! More information: http://www.Bluetooth.com Implement Bluetooth software and hardware in your products and systems Help advance Bluetooth functionality by supporting the working groups committees Got a new usage model? Submit a request Insure interoperability via Un-plugfests Help support native operating system development Provide test hardware to Microsoft Bluetooth Stack In Windows Ken Ray and Stan Adermann Software Development Engineers Windows Division Microsoft Corporation Agenda Bluetooth Architecture in Windows Goals Components of the Stack Functionality Opportunities for IHVs and ISVs Applications Services Devices High Level Goals PC work with all devices Bluetooth Devices as PC peripherals Bluetooth Devices as PC companions Bluetooth Devices bridge to network resources through a PC Easy to configure and operate Extensible architecture Platform for third parties to add value Scenarios Device configuration: Syncing and transfer through OBEX Files Pictures Vcards Dial up Networking Discovery Bonding Cell as modem Null Modem for Peer to peer Generic RFComm applications Non-OBEX synchronization Other serial-type applications Technical Requirements Bluetooth 1.0 Type II device classification supported Required profiles Bus Management Infrastructure Device and radio configuration Control panels System Trays Extensible framework for value adds Devices Profiles Bus mgmt software RFComm applications Object Exchange and special object handling RAS and TAPI over Unimodem Bluetooth Stack Diagram OBEX.DLL TAPI WinSock2 UNIMODEM.TSP SDP/Advisor MODEM.SYS AFD.SYS HID AUDIO BTHMODEM.SYS RFCOMM.SYS BTHPORT.SYS Stack Components BthPort L2Cap / HCI Hardware abstraction: Serial, USB… Enumeration of Found Bound Services SDP/Management UI Bus management: User notification of newly discovered devices User assisted Configuration and Bonding Configuration of radio Local Service Exposure and Publication Stack Components RFCOMM RFComm Profile TDI interface for WinSock (AFD) Bus enumeration for DUNs BthModem (a WDM modem) OBEX.DLL Object Exchange 1.2 Bus Agnostic BthPort Support Currently Defined buses: USB, Serial, 16550 Plug and Play events Bluetooth Request Blocks SDP Provide a “builder” interface to easily create a service record Kernel mode Client drivers can submit a list of UUIDs to search for on all newly discovered devices or initiate a SDP search outside of device discovery BThPort will search for all the services in the browse group hierarchy User mode Initiate searches Browse service records Management UI Present user with devices in range and bound devices Allows the user to easily change the relationship with remote device Provide unobtrusive PIN and authorization notifications UI is accessible from third-party applications for a standard user experience Advanced features Filter devices based on COD or address Local radio settings Manage power policies OBEX Full OBEX 1.2 implementation: Put Get SetPath Definable transactions COM API Extensible to other media and transports OBEX OBEX.DLL OBEXBT.DLL SDP OBEXIrDA.DLL OBEXIP.DLL WINSOCK 2 ? RFCOMM Modem.SYS OBEX BTHSER.SYS WINSOCK/AFD/TDI FDO PDO PDO DUN/Lan Access RFCOMM.SYS Socket FDO BTHPORT.SYS PDO File Transfer/OBEX Opportunities To Add Value RF comm applications OBEX applications/extensions Bluetooth management application New device types and/or class drivers Radios on new hardware buses RF Comm Applications Applications looking for virtual serial ports not supported Legacy TAPI/Unimodem applications see peer devices as NULL Modems Applications enumerate Modem/Serial Devices through Unimodem RF Comm Applications Winsock allows for dynamic discovery and communication Talk to the device, not to the conduit (“My Laserjet” versus LPT2) Once bonded device is in range the application can find and use it Allows for multiple remote connection to same service Not necessary to manage multiple virtual COMx ports OBEX Applications Examples Server Photos Vcards (not “in the box”) Simple databases Registration New Obex Commands and types Application can register as handler for custom commands Client Discovery Navigate directory structure (enumerate objects) Push Pull objects