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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/