Mark and Sweep
Mark-and-Sweep is a tool that allows you to characterize
wireless network and broadband connection of a neighborhood.
Data is a dump from a PostgreSQL DB.
Overview of the Methodology
Our method for collecting network information focuses on
achieving two goals: (1) ensuring an accurate set of collected data;
(2) maximizing the amount of data collected for the amount of human time
invested in taking measurements.
Pass 1 is a scaning phase.
The goal of the first pass is to determine which APs are in an area,
approximatedly where those APs are located, and where their signal strength
is the strongest.
During the first pass, can all streets in the targeted area at least
twice (usually once per side) using kismet.
Use gpsd and kismet at this phase.
The latest kismet version in Mark-and-Sweep
software contains some modification to output more information
Based on the data collected in Pass 1, we determine which
access points to measure in depth and the optimal lications for
such measurements. The preprocessing has to parts:
AP Pruning: The list of APs is pruned to include only unencrypted
APs with an SNR of 20 dB or larger.
Given the list of APs, we identify the location where each AP's signal
was the strongest. We then determine an order in
which to visit these locations that minimizes driving time.
Currently, this is done manually.
Once a list of APs and the test locations were identified.
We put it in a file and execute a program called ap_info
using the file as an input. It brings up navit with the
positions of the APs. For detailed information, consult README
Pass 2 is a active measurement phase.
The second pass of war driving collects detailed wireless and wired
network measurements from targeted access points. We usea a combination
of kismet, wicrawl, and navit in this pass.
ap_info tells you to make a stop and press enter
when you approach close to the location of measurement.
When you press enter, wicrawl automatically does the measurement.
Please contact dongsuh at cs.cmu.edu if you have any inquiry.