Short Message Service (sms) security solution for mobile devices

c. Hidden 
Processes 
The manual checklist to disable processes can only disable user 
accessible processes. There may be other system processes that may be 
running the background that are invisible to and inaccessible by the user. It is 
assumed that the demands placed by such processes are constant and can be 
eliminated by subtracting the baseline measurement data from the other data. 
d. 
Correct Algorithm Implementation
The experiment is based on Microsoft’s implementation of the 
encryption algorithm. It is assumed that these implementations are correct and 
representative of the types of encryption schemes. 
 
3. Data 
Collection 
Before the start of each measurement, a checklist was used to ensure that 
the critical settings that may affect the readings are consistent. For example, the 
wireless access for Wifi and GSM are turned off because they may introduce 
variable power consumption figures based on the detected infrastructure signal 
strength. The number of active process running on the device is also kept 
consistent so that the available memory and CPU demands are kept consistent. 
The detailed checklist is attached at Appendix A. 
The log file that is generated was manually analyzed to determine the 
number of iterations that will result in the change in battery power levels. Figure 
17 shows a sample of the output file. 

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Figure 17. Sample Output Log File 
In the log file in Figure 17, the battery power level changed from the 81%-
100% band to the 61%-80% band at the 151st iteration and moved on to the next 
band of 41%-60% at the 447th iteration. Therefore, 296 iterations of iterations 
consumed 20% of the battery power level. 
However, the total consumption figure includes the logging of the data for 
each iteration. Therefore, another set of baseline results, comprising all 
operations not related to encryption, was collected, and subtracted from the 
measurement results to derive a more accurate indication of the power 
consumption attributed to the encryption operation. 
Sufficiently large sample sizes were collected to ensure that each set of 
reading is statistically robust. The mean and standard deviation is then calculated 
based on a normal distribution. The raw data collected are attached at Appendix 
A. A summary of the results is shown in Table 4.