seung-hoon lee, sewook jung, alexander chang, dea-ki cho, and mario gerla network research lab...

Seung-Hoon Lee, Sewook Jung, Alexander Chang, Dea-Ki Cho, and Mario Gerla

Network Research LabDepartment of Computer Science

University of California, Los Angeles

Overview of wireless networks in HealthNet Bluetooth networks in HealthNet A new protocol using BT 2.1 Simulation Conclusion

Interests in health care considerably increased BodyLAN based wireless sensor platforms Monitoring patient status

Sensor

Network

Wireless networks for cable replacement

Sensor

Wireless networks for cable replacement◦ Issues: Small, cheap, power efficient◦ Wi-fi, ZigBee, Bluetooth

Sensor

Bluetooth◦ Small enough being attached on sensors◦ Cheap, power efficient◦ Widely being used – Most of cell phone, laptop

Issues◦ Long connection delay

Connection establishment: 5 ~ 10 seconds◦ Causes severe problem on time critical applications (i.e., emergency health applications)◦ BT cannot be utilized for EMERGENCY uses.

Bluetooth 2.1◦ Recently published (July 2007)◦ Introducing new enhancement features

Customizing two new features of BT 2.1◦ EIR (Extended Inquiry Response)◦ SSP (Secure Simple Pairing)

Bluetooth 2.1◦ Recently published (July 2007)◦ Introducing new enhancement features

Customizing two new features of BT 2.1◦ EIR (Extended Inquiry Response)

Original purpose: Inquiry Response message Propagating emergency data

◦ SSP (Secure Simple Pairing) Original purpose: security mechanism for data Protecting EIR data

Comparison of data dissemination stages◦ Bluetooth 2.0

Peer discovery: Find other peers within the communication range Paging: Connection setup Connection established: Data delivery

◦ Bluetooth 2.1 Peer discovery

Bluetooth 2.0

Master

Inquiry

InquiryResponse

Slave

Inquiry Response

Page

PageResponse

Page Response

InquiryScan

Page Scan

Master Response

SlaveResponse

Slave Response

Peer Discovery Paging Procedure

Data Delivery

Tx slot Rx slot Tx slot Rx slot Tx slot Rx slot

Tx slotRx slot Tx slot Rx slot Tx slot Rx slot

Inquiry Page Master Response

Connected

Bluetooth 2.0◦ Peer Discovery

Master

Inquiry

InquiryResponse

Slave

Inquiry Response

Page

PageResponse

Page Response

InquiryScan

Page Scan

Master Response

SlaveResponse

Slave Response


Data Delivery




Connected

Inquiry


Master

Inquiry

InquiryResponse

Slave

Inquiry Response

Page

PageResponse

Page Response

InquiryScan

Page Scan

Master Response

SlaveResponse

Slave Response


Data Delivery




Connected

InquiryResponse

Bluetooth 2.0◦ Paging

Master

Inquiry

InquiryResponse

Slave

Inquiry Response

Page

PageResponse

Page Response

InquiryScan

Page Scan

Master Response

SlaveResponse

Slave Response


Data Delivery




Connected

Exchange device informationChannel synchronization

Bluetooth 2.0◦ Connected

Master

Inquiry

InquiryResponse

Slave

Inquiry Response

Page

PageResponse

Page Response

InquiryScan

Page Scan

Master Response

SlaveResponse

Slave Response


Data Delivery




Connected

Connection establishedData delivery


Inquiry

InquiryResponse

Master

Inquiry

Inquiry

Slave

Inquiry Response

InquiryScan EIR

Tx slot Rx slot

Data Delivery

1250us

Rx slot Tx slot

Peer discovery Data Delivery

Bluetooth 2.0◦ EIR Data Delivery

Data delivery

InquiryResponse

Master

Inquiry

Inquiry

Slave

Inquiry Response

InquiryScan EIR

Tx slot Rx slot

Data Delivery

1250us

Rx slot Tx slot

Peer discovery Data Delivery

EIR based data delivery◦ Connectionless◦ Not protected by BT Security mechanisms

Secure Simple Pairing (SSP)◦ Customizing SSP procedures◦ Protecting EIR data

◦ PKI based security method◦ Keys generated by SSP stages◦ Encrypt/Decrypt EIR data with the keys

Simulation◦ NS2 + UCBT + BT 2.1 implementation

UCBT: Bluetooth simulation module UCBT not supporting BT 2.1 ( BT 2.1 recently published)

HealthNet Scenario◦ Patient monitoring system without any network infrastructure.◦ Emergency data delivered by Peer-to-Peer overlay◦ Three different nodes:

Patient: Emergency data source (static) Nurse: Delivering data by P2P (mobile) Data Collector: Collecting data (static)

Patient

Body Sensors

Nurses (Mobile)

Collection Center

peer-to-peer

Our protocol using BT 2.1 works a lot better than the conventional scheme

Number of nodes: VariousNode Speed: 1 m/sArea: 50x50 m2

Our protocol using BT 2.1 works a lot better than the conventional scheme

Number of nodes: 30Node Speed: 1 m/sArea: Various

Resolving a connection delay problem of Bluetooth devices in HealthNet with keeping the same security level◦ Customizing EIR and SSP

Simulation results confirm the improvement of BT 2.1 based data delivery◦ Delay and Power Consumption

Bluetooth devices are applicable for emergency applications in HealthNet

Questions?

seung-hoon lee, sewook jung, alexander chang, dea-ki cho, and mario gerla network research lab...

Documents

data deliveryconnectionlessnot

peer discoveryinquirybluetooth

peer discoverybluetooth

new features of bt

keyssimulationns2 ucbt

p2p mobiledata collector

network infrastructure

healthnetbluetooth networks