Abstract:
Due to day-to-day advancements in the technology, cellular mobile operators
around the world are facing higher data-rate demands and novel security issues.
The emerging issues are basically the result of the evolving features of technology
advancement. Therefore, there is an urgent need for specific modifications in the
existing security mechanisms used in cellular communication systems, in order to
enable them to face evolving security challenges.
This thesis focuses on analysis the existing security mechanisms used in GSM
(Global system for mobile) and proposes necessary modifications in them in order
to enhance security. In GSM generally three linear feedback shift registers are used
to fragment key in data encryption mechanism. In the dissertation, it is proposed
that in order to improve the security, the number of registers is increased, then
the number of combinations also increases. As combinations increase, the vulnerability of intercepting the encryption key decreases that enhances the security of
the system.
Moreover, a closed-form formula is developed to calculate the number of combinations of the session key if it is fragmented into a number of registers. The results
are plotted to show the trends of the number of combinations and the vulnerability
level of interception with respect to the number of registers. It is observed from
the simulations that when the number of registers is increased, the number of combinations also increases; on the other hand the vulnerability level of interception
decreases. In this way, personal data or information is protected and hacking of
data becomes difficult.
The derived formula can be used for the analysis of security mechanism in GSM,
wireless sensor networks and internet of things (IOT).
