This document describes a proposed sniffer device to detect lost mobile phones. Each mobile has a unique IMEI number transmitted when turned on, which the sniffer would detect using a small base station and directional antenna. The sniffer would operate at a different frequency than local cell towers to avoid interference. Software would track the IMEI number of lost phones and the design aims to be low-cost, low-power, and mobile to help recover lost phones.

1. SNIFFER FOR DETECTING LOST
MOBILES
Presented by
Sivani.R
14A81A05B0
III CSE-B

2. Contents
Introduction
What is IMEI
What is a sniffer?
Working of sniffer device
Designing for the sniffer
Advantages
Disadvantages
Conclusion

3. Introduction
The main scope of this is to detect the Lost
Mobiles
Though the effective way for blocking of the
lost mobile to prevent making or receiving the
calls has been done by the manufacturers of the
mobiles with the help of IMEI number
Sniffer has to be designed very precisely and size
should be reduced for mobility and or the
detection

4.  Each mobile device has IMEI
number(International Mobile Equipment
Identity)
When a phone is switched on, this unique IMEI
number is transmitted and checked against a data
base of black listed or grey listed phones in the
network’s EIR (Equipment ID Register).
Grey listing allow the phone to be used, but it can
be tracked to see who has it(via the SIM
information).
Black listing the phone from being used on any
network where there is an EIR match.
What is IMEI ?

5. What is a sniffer?
The sniffer is basically a transceiver that works
in the frequency which is the special unused
range that is operated by service provider
(or)
 It can be designed to operate at a frequency
that is of much different frequency than the
one that is being used.

6. Sniffer detector for lost mobiles

7. Working of sniffer device
A sniffer can also be used legitimately or
illegitimately to capture data being transmitted
on a network.
 It gives the normal operation of the mobile with
the base station and there is a BTS that acts as a
middle man in the process of communication
between the mobile and the MTSO which is
popularly known as MSC or Mobile Switching
Centre .

8. Working

9. Sniffer communication
Fig: the sniffer shown in fig tries to communicate
with lost mobile.

10. Designing for the sniffer
Design of a sniffer base station.
 Design of unidirectional antenna.
 Software that is used for tracking the lost mobile
phone’s IMEI number(Software tracking).

11. Sniffer base station
 The sniffer is a small base station, it includes
transceiver section.
 It should not operate at a frequency equal to the
frequency of the cell.
 It should operate at a frequency that is much
different from the frequency of the current cell
in which the operation of detection is being
carried out.

12. Unidirectional antenna
The directional antenna acts as the eyes for the
sniffer for the purpose of the detecting the lost
mobile phones.
Antenna is a device which works at specified
frequencies range for transmitting or receiving the
data signal.

14. Software Tracking
 The software is used for the tracking of the lost
mobile phone.
 The software that is to be designed in such a way
that the software has the input as the IMEI
number of the lost mobile phone.
 However the C is most preferred as it is easily
embedded with the chips.

16. Advantages
This method is used for finding the lost
mobiles effectively
Cost effective
low power consumption
Easy for the mobility

17. Disadvantages
Though this method appears to be a little bit
complex involving the design of the sniffer.
 The power of the mobile should be good
enough the mobile phone should not be in the
shadow region.
Networks are becoming more and more
complicated as they expand, and it’s a very
time consuming and tiresome task to pin point
a problem.

18. Conclusion
This topic deals about the idea of development
“Sniffer for the detection of lost Mobiles” paves
a way by means of which the lost mobiles can
be recovered. But the process of detection is yet
to be developed through the software and demo
has been developed.