Week 15

This week I continued working on the Android randomness collection.

Networking:

First, I wrote a simple server program using Java sockets to accept and print any incoming communication. I then wrote a corresponding client program and ran both on the same machine. After I got this working, I verified that they also worked on separate machines. With this working, I modified the client program for Android and ran it on the Nexus S. This process mainly involved creating a new thread to do the network communication since Android does not allow this from the UI thread. This allowed me to get working communication between the Android phone and a server.

Next, I wrote the final server program. The networking is very similar to the previous program, but I modified the structure to spawn a new thread for every client. I then wrote synchronized methods to separate the messages based on type (wifi, bluetooth, antenna) and write them to files local to the server.

Android Services:

As stated in my previous post, I want to alter my existing Android code to use services so that the user doesn't have to leave the collection app open for it to do its job. Therefore, I did some research on services and the code needed to implement them. I followed instructions I have found online, and have modified the previous bluetooth program to use a service. At present, I am debugging this since the service doesn't ever seem to start. I am confident however, that I will resolve this quickly, and that once I do, the other two parts will be easy to finish.

Week 13

Last week, I began working on an Android App to collect data on available wifi networks. This week, I was able to finish this app as well as to write apps to collect bluetooth and cell tower data.

Wifi and Bluetooth:

The Android API provides the built in classes WifiManger and BleuetoothAdapter. I was able to use these classes to set up BroadcastReceivers. The apps continuously scans for wifi/bluetooth networks and upon completion, the respective BroadcastReceiver gets called to print the data.

Cell Towers:

The Android API provides the built in class TelephonyManager. This class is very helpful, but I ran into a problem using its getAllCellInfo method. Apparently, this method is not supported on Nexus phones and therefore always returns null. Therefore, I was not able to access the built in CellTower Objects. However, I was able to use the getNeighboringCellInfo method to get the RSSI, Cell ID (CID) and Location Area Code (LAC) for each available cell tower.

I was able to test all three apps, and they seem to be working well.

I then began learning more about Android services. These are essentially processes that can be run in the background. I would like to convert my current code to make use of services so that the user doesn't need to worry about anything other than starting and stopping the app. This will be one of my main goals next week.

Since the end goal is to deploy this app on many phones for data collection, the goal is to have each phone send its acquired data back to a central location. I will therefore write a server application to collect and store the data being sent by the test apps. I plan to write this program next week and deploy it on the spqr bicuspid server.

Finally, I will be on vacation the week of August 5^th, so my work will continue on August 12^th.