1. Bubble-Sensing : Binding a sensing task to the physical world using mobile phones

2. INTRODUCTION
Here we present the bubble-sensing system that support the persistent sensing of a particular location , as required by user requests . Conceptually, a user with a phone that has opted into the bubble-sensing system visits a location of interest, presses a button on his phone to affix the sensing request to the location, and then walks away . The sensing request persists at the location until the timeout set by the initiator is reached.

3. Bubble-Sensing
Sensing tasks are created and maintained in the bubble-sensing system through the interaction of a number of virtual roles.
Virtual roles-
Bubble creator 
Bubble anchor 
Bubble carrier Sensing node

4. Bubble-Sensing

5. Bubble-creation phase
Bubble Server
Bubble Anchor
Bubble Creator
Mobile Sensor
Mobile Sensor

6. Bubble Maintenance Phase
Due to uncontrolled mobility of the creator , the creator may leave the bubble location while task is still active .
So to anchor the bubble to the location of interest  we use bubble anchors .
Two variants for bubble anchor selection :
1. Location based
2. Mobility based

7. Bubble Restoration Phase
Bubble-Server
Bubble Carrier
Bubble Anchor
Mobile Sensor
Mobile Sensor

8. Architecture Programming languages Communication Sensor Classifier
System integration

10. Problems Hold the bubble in the area of interest.
Recover from lost bubble.
Exploit heterogeneous devices.

11. Privacy and security concerns
The sharing of device resources with unknown third parties.
Individual is privacy concerning their daily activities is at risk from other users if bubble sensing system is misused.

12. Related Work
As the mobile phone is ubiquitous, and the discussion of a mobile phones used as a sensing device has some history no large-scale mobile cell phone sensor network shave yet been deployed in practice.
In the last few years, the smart phone market has grown rapidly (e.g. , Nokia N95, Apple iPhone ) , cultivating ground for research on mobile sensor networking.

13. Conclusion
So mobile sensor nodes collaborate and share sensing and communication resources with each other in a cooperative sensing environment.
So we presented an approach to support persistent location-specific task in a wireless sensor network composed of mobile phones.

14. References
A.T. Campbell, S.B. Eisenman , N.D. Lane, E. Miluzzo , R.A. Peterson , People-centric urban sensing, in: Proc. of 2nd ACM/IEEE Intl Conf. on Wireless Internet, WICON06, ACM Intl Conf. Proc. Series, vol. 220, No.18,Boston, Aug 25, 2006, (Invited Paper).
J.Burke , D.Estrin , M. Hansen, A. Parker, N.Ramanathan , S. Reddy, M.B.Srivastava, Participatory sensing, in: Proc. of 1st Workshop on Wireless Sensor Web, WSW06,Boulder, October 31, 2006.

15. Contd..
T.Abdelzaher , Y. Anokwa , P.Boda, J.Burke,D. Estrin,L.Guibas, A. Kansal,S. Madden and J. Reich, Mobiscopes for human spaces,IEEE PervasiveComputing 6(2) (2007)
S.B. Eisenman, A.T. Campbell, SkiScape sensing, in: Proc. of ACM 4th Intl Conf. Embedded Networked Sensor Systems, SENSYS04, 2006.

16. Thank You