Short Message Service (sms) security solution for mobile devices

F. THESIS 
ORGANIZATION 
The remainder of the thesis is organized as follows. Chapter II provides 
an overview of the security issues surrounding SMS, from the GSM infrastructure 
to the mobile device. This Chapter also highlights some applications where the 
security of the SMS is of paramount importance if it is to be used as a delivery 
mechanism in the application. 
Chapter III discusses the issues surrounding the use of encryption in 
mobile devices. It highlights some of the key considerations when choosing a 
suitable encryption scheme. The results of an experiment to measure some of 
the performance metrics are also discussed in this Chapter. 
Chapter IV describes the Secure Chat demonstration application that was 
developed to show how SMS messages can be secured using encryption.
Chapter V concludes the thesis and provides recommendations for further 
research in this area. 

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II. OVERVIEW 
A. OVERVIEW 
The GSM network has grown rapidly since its introduction in the early 
1990s, with the second billionth GSM user connected in Q2 2006 [4]. The 
number of SMS messages sent has also seen explosive growth, with an 
estimated one trillion SMS messages sent globally in 2005 [5]. With the vast 
amount of information transacted using SMS, it is important the SMS text 
messages be adequately protected against eavesdropping and modification.
A discussion on SMS security is especially challenging because SMS 
messages transverse across different transmission media, undergo multiple 
protocol translations, and are processed by different devices operated by 
different organizations. As such, the overall security of SMS will be only as strong 
as the weakest link in the whole chain.
This Chapter discusses the security of SMS in three parts: at the GSM 
infrastructure level, at the SMS application layer, and at the mobile device. The 
last section of the Chapter discusses other potential uses of SMS if its security 
can be assured.