-priyanka, madhurima. idea of wireless leash your devices go…. wherever you go!!

LUE CONNECT

-Priyanka, Madhurima

IDEA of WIRELESS LEASH

Your devices go…. Wherever you go!!

Project Goal

Fast and easy devic

e discovery

Maintain Proximity

Power Efficient

Context

Aware

BlueConnect

Fast and easy devic

e discovery

Maintain Proximity

Power Efficient

Context

Aware

Blue Connect

Using Visual Tags to Bypass Bluetooth Device Discovery-Priyanka

Bluetooth Tracking without Discoverability-Madhurima

BLUETOOTH TRACKING WITHOUT DISCOVERABILITY

Location and Context Awareness LoCA ,2009 Tokyo, Japan

Aim: Indoor Location Tracking• Locate user in a building• Tracking of users in timescale• Tracking of Multiple Users• Easy to use.• Existing hardware.

Existing work and proposed solution

• WiFi: – High power demand– Set up and maintainance– Handset requires WiFi

“ON”• Bluetooth (RSS,

FingerPrint)– Beacons– Scan takes 10.24s– Privacy

• Solution:Track Bluetooth Device without making Discoverable

•Contribution: Faster Connection Setup and Monitoring

Bluetooth ConnectionL2CAP(Logical Link Control and Adaptation Protocol )

• Protocol, Segmentation and reassembly

ACL(Asynchronous Connectionless Link)

• Packet Switched Link

Bluetooth Connection Procedure

Inquiry Scan

Inquiry Response (remote device's address and clock)

Manual Device Selection

Paging

Connection

Why Bluetooth Discovery takes so long?

A A A A A A A A A A A A A A A A B B B B B B B B B B B B B B B B

16 Channel A frequencies

16 Channel B frequencies

A A A A A A A A A A A A

256 times in 1 iteration

B B B B B B B B B B B

256 times in 1 iteration

Inquiry scan

PagingA A A A A A A A A A A A A A A A

Master

Slave

Tscan <0,1.28, 2.56s>

Twindow

10.24ms

11.25ms

B B B B B B B B B B B B B B B B

Enquiry Based

Conection Based

0 2 4 6 8 10 12 14

DiscoveryPaging

Connection Monitoring

• RSSI Received Signal Strength Indicator– Monitor rate can be 1Hz

• Link Quality (LQ) – Require no extra data

• Echo response time– Monitor Rate – 40ms– Requires more Battery Power

0

-14

RSSI

0 5 10 15 20 25 30 Distance(m)

Power Consumption

Power Consumption

Idle

Only W

iFi

Bluetooth

On

Cont.sca

nned

Echo (m

ax ra

te)

Cont. RSS

I

Echo(30s)

Echo(20s)

Echo(10s)

Ech0 (5

s)

RSSI(3

0s)

RSSI(2

0s)

RSSI(1

0s)

RSSI(5

s)0

50

100

150

200

250

300

350

400

450

500

G1 N80

State

Pow

er C

onsu

mpti

on (m

W)

ConclusionPositive• Faster Update Rate.• Variable Update Rate.• No Scanning.• Privacy

Negative• Devices must be Known.• Connection Limits.

Using Visual Tags to Bypass Bluetooth Device Discovery

By D. Scott, R. Sharp, A. Madhavapeddy, E. Upton

- ACM SIGMOBILE Mobile Computing and Communications Review, 2005.

Priyanka Bagade

Standard Bluetooth Device Discovery Model

– takes 10.43s to complete in error free environment

BD_ADDRBD

_ADDR

BD_ADDR

BD_ADDR

• Inquiry

John

Alice

Bob

Martin

Select Photo

Device Discovery

Device Selection

Select Photo

Select Physical Device

Standard Bluetooth Device Discovery

Comparison of Standard Bluetooth Device Discovery and Tag-Based Device Discovery

Tag-Based Device Discovery

Sync Marker

Check Sum

BD_ADDR

Application Specific Data

Tag Reading

Visual Tag – System Architecture

48 bits

15 bits63 bits

Download Music using Bluetooth

1

2

3

Download Music Track 2

Tag-based Connection Establishment and Content Selection

Web Server

Camera PhoneService Attribute

Transaction

HTTP Response

BD_ADDR, File ID

Service Search Request

HTTP Get

Performance Evaluation

• Speed

Performance Evaluation(Contd.)

• Usability – Number of button presses reduced Conventional system ~ 10 -> Device and item selection Visual tag system – just 1 !!! Capture the visual tag

• Scalability – Performance does not get affected by increase in number of neighborhood Bluetooth devices and number of options provided by Mobile service

• Security – Authentication and privacy are provided using digital signature and Bluetooth’s connection level encryption

Usage Scenarios

• Stock Querying

Usage Scenarios(Contd.)• Use of Visual tags to quickly learn Server

configuration

Usage Scenarios(Contd.)• Active Visual Tags – Generated Dynamically from a PC display • Tested in marketing posters used for events in Europe

Conclusion

• Introduces new approach to maximize the potential of an already popular device (Bluetooth and Camera phones)

PROS• Reduces Bluetooth Device Discovery time significantly• Provides convenient way to select a required service from

number of mobile services• Easy to implement as relies entirely on commodity

hardwareCONS• Requires camera phone • Data capacity is very less as compared to RFID

Summing it all…

Visual Tags to Obtain BD_Address

Bluetooth tracking without discoverabilitySynchronization for paging and proximity monitoring

References• [1] D. Scott, R. Sharp, A. Madhavapeddy, E. Upton, “Using visual tags to

bypass Bluetooth device discovery,” ACM SIGMOBILE Mobile Computing and Communications Review, v.9 n.1, January 2005 [doi>10.1145/1055959.1055965] http://portal.acm.org/citation.cfm?id=1055959.1055965

• [2] S. Hay and R. Harle, “Bluetooth tracking without discoverability,” LoCA 2009: Proceedings of the 4th International Symposium on Location and Context Awareness, 2009. http://www.springerlink.com/content/h6p4104852184rj8/