WIFI USABILITY Reg Arvidson

Idea  Track signal variances throughout the day  Get a feel for the “usability” of a WiFi access point (or location)  Present this as a map to easily spot “lagging” areas

Implementation  Create a client program to collect WiFi/GPS data and submit to a server  Server catalogues data into a database while waiting to serve map requests  Clients can request a map from the server showing WiFi data for GPS points

High-Level Architectural View GPSWiFi Client Server GPS/WiFi Data Map! If it was only that easy…

Client View (Data Collection) GPS_Parser COM_Access WLAN_Access GPS Serial Data WiFi Signal Data WiFiGPSDataUnitcURL Internet

Server View (Data Collection) postdata.php Apache Web Server MySQL Database Internet

Server View (Data Service) index.php Apache Web Server MySQL Database Internet testdisp.php kml.kml

Client View (Data Service) Internet Your favorite web browser! Or Google Earth…

Data Collection  Flag a GPS fix if at least 3 satellites in view  Utilize fix data to time 5 second intervals  If fix, poll WiFi interface for access points  Tag SSID and signal strength to GPS fix  If internet available, submit data, else store for later!  Runs in background, works even when using any access point or the Internet

cURL Library  Created a URL to pass data to PHP script  &lon= &lat= &ssid=UCF&sig=23...  cURL library allows easy usage of GET  If GET fails then we leave data in buffer and try again later

Data Buffering  A cURL failed GET leaves data in a buffer  Allows roaming off the network, across town, local pub, etc  Upon reconnecting with friendly access point will push data to server

Displaying Mapped Data  Going to homepage, index.php, triggers creation of KML file, kml.kml through use of testdisp.php, with all collected data from MySQL database  Automatically loads map using this freshly created KML file  Mapped data shows signal strength of SSID tagged to a GPS point, marker colors reflect signal strength  Can also load KML into Google Earth for a much more interactive view

Problems  Laptop Died  Created new database  Recovery of project files  Rebuilt for new target machines  Recollection of data  Lack of data (due to stated death)

Improvements  Can easily add additional data in minutes  Security algorithm (if used), for example  Better data transfer method  Direct connection to SQL server for instance  DATA DATA DATA DATA DATA

Questions? ?