Short Message Service (sms) security solution for mobile devices

1. AGENCY USE ONLY (Leave blank) 
2. REPORT DATE
December/2006 
3. REPORT TYPE AND DATES COVERED
Master’s Thesis 
4. TITLE AND SUBTITLE
Short Message Service (SMS) Security Solution 
for Mobile Devices 
6. AUTHOR(S)
Yu Loon Ng 
5. FUNDING NUMBERS 
7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 
Naval Postgraduate School 
Monterey, CA 93943-5000 
8. PERFORMING ORGANIZATION 
REPORT NUMBER
9. SPONSORING /MONITORING AGENCY NAME(S) AND ADDRESS(ES) 
N/A 
10. SPONSORING/MONITORING 
AGENCY REPORT NUMBER
11. SUPPLEMENTARY NOTES
The views expressed in this thesis are those of the author and do not reflect the 
official policy or position of the Department of Defense or the U.S. Government. 
12a. DISTRIBUTION / AVAILABILITY STATEMENT
Approved for public release; distribution is unlimited. 
12b. DISTRIBUTION CODE
13. ABSTRACT (maximum 200 words)
 
This thesis focuses on the security of Short Message Service (SMS) and the Global System for Mobile 
communication (GSM) network and the use of encryption to protect SMS messages. A detailed study of 
the GSM network and SMS protocol, and encryption schemes was conducted to understand the properties 
of different encryption schemes and their applicability to SMS messages. An experiment was conducted to 
measure the actual performance of various encryption schemes on a modern smart phone device. An 
analysis of the encryption scheme properties and the performance measurement was then conducted to 
select a suitable scheme for SMS encryption. The selected scheme was implemented in the form of a 
Secure SMS Chat application to validate the viability of the selected encryption scheme. Potential 
applications of secure SMS in military settings are also discussed.