200 likes | 313 Vues
INFOTECH Seminar Advanced Communication Services SS 2003. Service Discovery based on the Bluetooth standard. Mentor : Stephan Rupp Student : Zhao ZHANG July 3, 2003. Application & Motivation. How to discover service?. 2.
E N D
INFOTECH Seminar Advanced Communication Services SS 2003 Service Discovery based on the Bluetooth standard Mentor : Stephan Rupp Student : Zhao ZHANG July 3, 2003
Application & Motivation • How to discover service? 2 ACS Service Discovery based on the Bluetooth standard
Questions? • How can services be identified? • How do element discover each other ? • Is Bluetooth perfect? 3 ACS Service Discovery based on the Bluetooth standard
Agenda • 1: introduction • 2:Bluetooth Protocol Stack • 3:Bluetooth Profile Sketch • 4:Service Discovery Protocol (SDP) • 4.1:Basic Principles of SDP • 4.2:How to find service? • 5:Bluetooth Security • 6:Bluetooth advantages and limitations 4 ACS Service Discovery based on the Bluetooth standard
Bluetooth – (Special Interest Group) No.1: GPRS Handy ThinkPad Laptop SIG No.1: PC card 1,900 Bluetooth Technology Manufactures 5 ACS Service Discovery based on the Bluetooth standard
Bluetooth Protocol Stack WAP 1.cable replacement layer 2.emulation of EA-232 serial ports WAE vCard/vCal Audio TCP/IP OBEX AT-commands PPP SDP RFCOMM TCS-BIN Provide data sevices to higher layer:multiplexing, packer,segmentation call control signal between Bluetooth units query for device information, services L2CAP 1.Link setup and control 2.security Host Controller Interface LMP • Synchronous Connection-Oriented (SCO) • Asynchronous Connectionless (ACL) Connection Interface between Baseband and higher layers Baseband 6 ACS Service Discovery based on the Bluetooth standard
Bluetooth Profile Generic Access Profile TCS-BIN Based Profiles Cordless Telephony Profile Internkom Profile Service Discovery Profile Serial Port Profiles Generic Object Exchange Profiles Dial-up Networking Profile File Transfer Profile Fax Profile Object Push Profile Headset Profile Lan Access Profile Synchronization Profile 7 ACS Service Discovery based on the Bluetooth standard
SERVICE DISCOVERY PROTOCOL (SDP) • What is UUID? UUID: Universally Unique Identifier UUID Aliase (16-bits or 32-bits) 128_bit_value = 16_bit_value * 2E96+ Bluetooth-Base-UUID 128_bit_value = 32_bit_value * 2E96+ Bluetooth-Base-UUID 8 ACS Service Discovery based on the Bluetooth standard
Service and Service description Service Attribute 1 Service Attribute 2 Service Attribute 3 . . . Service Attribute n Service Service Record • What is Service? • What is Service Record? • What is Service Attribute? 9 ACS Service Discovery based on the Bluetooth standard
Service Attribute • Attribute ID 16-bit unsigned integer • Attribute Value • Data Element 10 ACS Service Discovery based on the Bluetooth standard
Data Element Type Descriptor Header Field Size Descriptor Data Element Data Field Type Descriptor Size Descriptor Data Field 5 bits 3 bits 11 ACS Service Discovery based on the Bluetooth standard
PDU of SDP • PDU:Protocol Data Unit PDU ID PDU Header Transaction ID PDU Parameter Length PDUparameters 12 ACS Service Discovery based on the Bluetooth standard
PDU Structure PDU Header PDU ID Transaction ID Parameter Length PDU Parameter Parameter 1 Parameter 2 ……………….. Parameter N Parameter Length of Bytes 13 ACS Service Discovery based on the Bluetooth standard
How to discover a service? Client Server service records database Service discovery application SDP Requests SDP Server SDP Client SDP Responses SDP_ErrorResponse 14 ACS Service Discovery based on the Bluetooth standard
Bluetooth Advantages and Limitations • Bluetooth Advantages Communication with others in a free space penetration • Bluetooth Limitations Range Limitation Transmission Rates Limitation Piconet Limitation 15 ACS Service Discovery based on the Bluetooth standard
Bluetooth Advantages and Limitations Piconet Limitation V8 V7 Piconet A Piconet B 10m V2 V1 V6 V3 V4 V5 16 ACS Service Discovery based on the Bluetooth standard
Bluetooth Security • Authentication • Authorization • Encryption 17 ACS Service Discovery based on the Bluetooth standard
Summary and Conclusion Bluetooth Protocols and Profiles what isimportantabout SDP? Bluetooth security Are there anyfurther developments or releases? 18 ACS Service Discovery based on the Bluetooth standard