Week 11

The next step in our survey of entropy sources will be mobile devices. Mobile devices are extremely prevalent, and commonly perform tasks that require a high degree of security. These devices offer the advantages of mobility and thus an unpredictable environment, as well as several embedded devices such as cameras and microphones. However, they are more susceptible to theft and lack the computing resources of more traditional machines.

I read a paper: “The Sources of Randomness in Mobile Devices” (from Masaryk University, Czech Republic). The authors do a study of the entropy gathering potential of mobile devices. They focus mainly on the microphone and camera inputs and through statistical analysis show that these devices are capable of providing truly random bits. They do not give a good idea however of the rate at which such bits might be generated.

For our project, I anticipate analyzing sources such as the microphone, camera, battery level, signal strength, and gps position. We might also be able to use some of the sources we have already examined such as bluetooth, wifi, and process statistics.

In order to investigate these sources, I have been learning how to create apps for the android operating system. Google provides a good training tutorial that I have been using. I have learned quite a bit by creating several apps with basic functionality. I have a bit farther to go in this training, but it should help me to create some apps to record the sources we are interested in.