A Comparative Study of Two Bluetooth APIs for Implementation in an Automated Wireless Identification System (AWIS) Sam Knights Rhodes University Supervisors: Dr G. Foster and Prof P. Clayton

Presentation Outline Brief Background and Motivation Brief Background and Motivation Methodology Methodology Results/Test Applications: Results/Test Applications: Windows API Windows API Widcomm API Widcomm API Discussion Discussion Future Work Future Work Conclusion Conclusion

Brief Background Individual animal identification and Individual animal identification andinteraction Behavioral patterns Behavioral patterns GPS, infrared imagery, GSM, satellite GPS, infrared imagery, GSM, satellite Bluetooth Enabled devices - collars Bluetooth Enabled devices - collars Transmit information when in range of other animals = “Encounter” Transmit information when in range of other animals = “Encounter” Transfer to Beacons (on trees/ rocks) Transfer to Beacons (on trees/ rocks) Motivation for using Bluetooth: Motivation for using Bluetooth: 10m range, low power and cost, small size 10m range, low power and cost, small size Dynamic nature of networks formed Dynamic nature of networks formed

Project Aims Investigate Bluetooth APIs Investigate Bluetooth APIs Device connectivity, data-transfer Device connectivity, data-transfer Limits to APIs flexibility, functionality Limits to APIs flexibility, functionality Feasibility of extending API Feasibility of extending API Motivation Motivation No standard API in Bluetooth specification No standard API in Bluetooth specification Only way to compare APIs Only way to compare APIs “Use tools available directly”… “Use tools available directly”…

Methodology - Approach Iterative development of test applications Iterative development of test applications Not complex, speed of development Not complex, speed of development Stages towards AWIS Stages towards AWIS 1. Simple inquiry, one device then many 2. Discover who went out of range 3. Build up Encounter log 4. Upload onto Beacons (Service Discovery) Compare each API in terms of functionality provided to complete each stage Compare each API in terms of functionality provided to complete each stage Test applications Test applications

Iterative Development Methodology Test Stage of System Implement AWIS Progress Start Research Evaluate

Pocket PC 2003 SDK, Windows CE Pocket PC 2003 SDK, Windows CE Rapid development, sophisticated IDE Rapid development, sophisticated IDE Windows API: Winsock and Virtual Serial Ports Windows API: Winsock and Virtual Serial Ports Not “easy or quick”, recommended Not “easy or quick”, recommended Widcomm API Widcomm API Most widely used, choice of proprietary API Most widely used, choice of proprietary API Different approaches to application development Different approaches to application development Windows insulate developer Windows insulate developer Widcomm protocol layer direct access. Widcomm protocol layer direct access. Methodology – Materials Software

iPAQ Pocket PC h4150 iPAQ Pocket PC h4150 Familiar UI, concentrate on software Familiar UI, concentrate on software Active Sync, fast testing of applications Active Sync, fast testing of applications Small, portable Small, portable DLink Dongle DLink Dongle Test broadcasting MAC Address Test broadcasting MAC Address Connect PC to Bluetooth Devices Connect PC to Bluetooth Devices Methodology – Materials Hardware

Methodology – Test Applications Virtual Serial Ports Virtual Serial Ports Experimented with Terminal Type Application Experimented with Terminal Type Application Connection, data transfer Connection, data transfer Winsock Winsock Discover devices and services Discover devices and services Widcomm Widcomm Discover devices, L2CAP Discover devices, L2CAP Field test – attached iPAQ to front desk Field test – attached iPAQ to front desk iPAQs running AWIS application iPAQs running AWIS application Bluetooth devices switched on Bluetooth devices switched on Encounter log written to a file Encounter log written to a file

Results

API Comparison - Documentation Virtual Com WinsockWidcomm Device Inquiry Service Discovery Information Transfer Rapid prototyping Functionality Flexibility Compatibility GENERAL AWIS      

API Comparison - Results Virtual Com WinsockWidcomm Device Inquiry Service Discovery Information Transfer Rapid prototyping Functionality Flexibility Compatibility GENERAL AWIS                   

API Comparison - Results Virtual Serial Ports Virtual Serial Ports No device discovery, limited service discovery No device discovery, limited service discovery Winsock Winsock “Network down” “Network down” Widcomm Widcomm Choice of stack access: Choice of stack access: L2CAP, RFCOMM, SDP, OBEX etc L2CAP, RFCOMM, SDP, OBEX etc Device discovery and Service discovery – L2CAP Device discovery and Service discovery – L2CAP Information transfer Information transfer L2CAP Connection vs OBEX L2CAP Connection vs OBEX

Discussion Virtual Serial Ports Virtual Serial Ports Familiar, low-level, no device inquiry functions Familiar, low-level, no device inquiry functions Winsock Winsock “Network down” – iPAQ had Widcomm stack “Network down” – iPAQ had Widcomm stack Wrapper class to extend API Wrapper class to extend API Widcomm Widcomm Approach allows flexibility and functionality Approach allows flexibility and functionality Simple Device discovery and Service discovery Simple Device discovery and Service discovery Extend API only by Encounter Class Extend API only by Encounter Class

Discussion Test done in CS department Test done in CS department Did the application discover all devices? Did the application discover all devices? Discovery when discovering a problem Discovery when discovering a problem Time taken for encounters? Time taken for encounters? Slow – 10s for inquiry Slow – 10s for inquiry Information uploaded correctly? Information uploaded correctly? Did AWIS applications interfere with each other? Did AWIS applications interfere with each other?

Discussion Limitation to Results Limitation to Results No hardware considerations No hardware considerations Experience limited to AWIS application Experience limited to AWIS application For developer: Stack incompatibility For developer: Stack incompatibility IPAQs the way to go? IPAQs the way to go? Sufficient for pilot study – rapid development Sufficient for pilot study – rapid development GUI not always ideal GUI not always ideal Not for actual implementation Not for actual implementation Fits into iterative development Fits into iterative development

Future Work Could look to some other technologies Could look to some other technologies ZigBee ZigBee Investigate more APIs Investigate more APIs Allow more interaction with stack, hardware Allow more interaction with stack, hardware Some other possibilities for the AWIS system: Some other possibilities for the AWIS system: Check employees are doing their job Check employees are doing their job Monitor human psychological behaviour Monitor human psychological behaviour

Conclusion Comparing APIs through testing Comparing APIs through testing Valuable to the developer Valuable to the developer Result: Widcomm most suitable Result: Widcomm most suitable Flexible but simple, functionality needed for AWIS Flexible but simple, functionality needed for AWIS Iterative development, rapid prototyping Iterative development, rapid prototyping AWIS works AWIS works Implementation issues overcome Implementation issues overcome Future work could be done Future work could be done

Questions?

Wireless Projects A. King : Peer-to-peer networking, Data transfer B.Clayton : Scatternets, Ad-hoc networking S. Knights : Application Programming Interfaces BLUETOOTH STACK B. Fox : Custom operating system image