Choosing the right mapping software
Using GPS Creating a map
from war driving data
Converting data to use on a map Adding extras to
your map
in this chapter
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146 Part II — War Driving
Enter the world of Geographic Information Systems (GIS) and plot your newly discovered war driving data on top of a professionally researched GIS mapping software. (See Figure 7-2.)
Mapping Overview
The essence of mapping a war drive is simple: generate a map of your area of interest and mark up the map using location coordinates.
But before we get into the step-by-step details, let’s cover some basic information about map- ping software, GPS technology, and data converters.
Mapping Software
Dozens of mapping programs are available for the casual user. Programs can be purchased for as little as $40 for a simple travel package with GPS support, on up to several hundred dollars for a business-grade program with sophisticated population and demographic tools. There are also free applications, but these tend to rely on Web-based mapping sources like MapQuest for map generation, which reduces effectiveness while on the road.
FIGURE7-1: Map of war driving results in West Los Angeles.
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Table 7-1 shows some common mapping applications and some features. The applications reflect the most common products used by the war driving community. If you have a preferred package, by all means, give that a try first.
Topographic features allow mapping software to present elevation data. This can be in the form of topographic lines on the map display, 3-D imaging, or a “knife-edge” point-to-point profile.
Topographic features help tremendously when you’re planning a long-distance Wi-Fi link (as dis- cussed in Chapter 13).
By far, the most popular war driving map generation program is Microsoft MapPoint. It’s more expensive than the rest, but the features and ease-of-use make it the best choice for war drivers.
FIGURE7-2: Diagram of GIS layers of information.
Table 7-1 Mapping Software Applications and Features
Developer GPS Imports Trip Topo- NetStumbler
and Title Interface “Pushpins” Navigation graphic Converter Features Available
Microsoft Streets Yes Yes Yes No Netstumbler.com
& Trips
Microsoft Yes Extensive Yes No StumbVerter,
MapPoint Netstumbler.com
DeLorme Street Yes Yes Yes No WiMap
Atlas USA
DeLorme XMap Yes Yes No Yes Perl script
DeLorme Yes Yes No Yes Perl script
TopoUSA
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148 Part II — War Driving
And yet, the excellent navigation and turn-by-turn route planning features in most popular mapping programs can make those old gas-station maps obsolete.
Microsoft MapPoint
This business-grade mapping program provides extensive “pushpin” features and Microsoft’s COM programming plug-in capabilities. At a retail price of about $300, it’s the most costly of the programs listed here. See Figure 7-3 for a screenshot of the MapPoint interface.
The pushpin feature is fairly common across digital mapping programs, although different names may apply. The MapPoint pushpin lets you place a marker anywhere on the map (manu- ally or automatically) with notes and other data assigned to the object.
The COM add-in ability is especially nifty, because it allows third-party developers to run pro- grams using the MapPoint mapping engine and data set. The most notable of these for war drive mapping is the StumbVerter program. StumbVerter is a free download, but donations are encouraged. StumbVerter takes exported NetStumbler “Summary” text files and automatically plots them on a map using the MapPoint engine and data.
MapPoint is also a powerful business tool including demographics, census data, and several geographic trend tools. Of particular note is the drive time calculator. Mark a location, select the drive time zone tool, enter the drive time, and the software will determine how far you can drive in, say, 10 minutes.
FIGURE7-3: The Microsoft MapPoint 2004 interface.
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Microsoft Streets & Trips
Streets & Tripsis a basic travel and street-level mapping program that provides the essentials for mapping and vacation planning. It includes route planning, turn-by-turn directions, GPS support, and locates points of interest. Streets & Trips costs about $40.
Although StumbVerter does not support it, Streets & Trips will read converted war driving files formatted for Microsoft MapPoint. For example, the Netstumbler.com site has a Web form that will convert the data and display it on-screen. (More on this later in the chapter.)
DeLorme Street Atlas USA
Street Atlas USAis a very popular mapping program, usable only in North America, that pro- vides the essentials for travel and vacation planning. It compares with Microsoft Streets &
Trips with one major advantage. A freeware conversion program is available that automatically formats a NetStumbler text file into the correct DeLorme format.
The WiMap Utility is a downloadable Windows program that reads NetStumbler Summary text files and creates a “latlon” file recognized by most DeLorme products, including Street Atlas USA.
Figure 7-4 shows the main interface for WiMap. The buttons on the left allow for useful selec- tion and formatting capabilities.
FIGURE7-4: The simple interface for the DeLorme-compatible WiMap Utility.
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150 Part II — War Driving
The Global Positioning System
The Global Positioning System, known as GPS, is made up of a number of satellites in orbit around the Earth. These satellites (24 active, with a few spares) maintain a precise position rel- ative to Earth. GPS receivers continuously receive updates of the position of all 24 satellites in orbit. By computing the distance from the receiver to each visible GPS satellite, your GPS receiver triangulates its position on Earth in the form of Latitude, Longitude, and Altitude.
Consumer-grade GPS receivers are not completely accurate. High accuracy is more costly, but most consumer GPS receivers using the new Wide Area Augmentation System (WAAS) or Differential GPS (DGPS) capability can give you a position accuracy of less than 3 to 5 meters. In the case of mapping results, often the maps you are working from are not entirely precise, either. Mapping accuracy is always a game of ever-increasing accuracy and the cost of obtaining that accuracy. For our purposes, though, a $100 GPS and $40 mapping software works perfectly.
How GPS Works
GPS works on the very basic principle of triangulation. Each satellite beams down a signal to Earth. It also beams down the time the signal was sent, and of course, which satellite the signal came from.
GPS is also about the most accurate time source available to consumers. Each satellite carries an atomic clock, and keeps your handheld unit timed to that clock. By knowing the exact time (to the nanosecond) that the signal left the satellite, the time when the signal reached the receiver, and knowing the speed of light, distance is computed. (See Figure 7-5.)
FIGURE7-5: GPS uses triangulation to find your position on Earth.
Distance C Distance B
Distance A
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When at least three distances are known (from three GPS satellites) the receiver’s position on Earth is known and recorded as latitude and longitude. If a fourth satellite is visible, altitude will also be computed.
Formats for Recording Latitude and Longitude
Altitude is pretty standard, measured in meters or feet. Latitude and longitude is another mat- ter. In its basic form, latitude and longitude is recorded as degrees, minutes, and seconds, north or south of the Earth’s equator and east or west of the Prime Meridian (the line that separates the Western and Eastern hemispheres).
Table 7-2 lists three different methods for recording latitude and longitude position in a data file. Additionally, there are hundreds of different map formats or datumsused to record latitude and longitude onto a paper or electronic map product. The most popular map datum used today is the World Geodetic System 1984 (WGS-84). Make sure your GPS is set to the same map datum as your mapping software. Most modern maps record the map datum being used somewhere with the map itself or with the software documentation. Note that North and East may also be represented as positive () numbers while South and West are represented as neg- ative (–) numbers (for example,34.07385 –118.23985).
Creating a Map
The procedure for mapping is a basic step-by-step process:
1.Gather data by war driving.
2.Export the data into a common war driving text format.
3.Convert the data into a format readable by mapping software.
4.Import the data into the mapping software as location flags or pushpins.
5.View the results.
I’ll cover each of these steps in the following sections.
Table 7-2 Several Formats for the Same Location
Coordinate Type Number Format Location of Dodger Stadium
Degrees dd.ddddd* N34.07385* W118.23985*
Degrees Minutes dd* mm.mmm’ N34* 04.431’ W118* 14.391’
Degrees Minutes Seconds dd* mm’ ss.ss’’ N34* 04’ 25.86” W118* 14’ 23.47”
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152 Part II — War Driving
Step 1: Gathering Data
To gather the data, someone needs to go war driving. See Chapter 5 for more on war driving. If you don’t have your own results, others may have posted their files. Try performing a Google search for Netstumbler NS1.
The minimum amount of data needed to make a map is the latitude and longitude of a sin- gle wireless access point. More information will make the map more interesting, but is not necessary.
Step 2: Exporting Into a War Driving File Format
NetStumbler has become the de facto standard when it comes to working with war driving data. Most war driving programs have a converter available to export into NetStumbler Summary Export format, also called “wi-scan summary with extensions.”
NetStumbler supports this format directly from the File menu. Click File ➪Export ➪ Summary. Then enter a file name using the .txt extension to ensure that Notepad or another text editor will be able to open the file directly. In this example, use summary.txt. For more about exporting file formats from NetStumbler, see Chapter 6.
FIGURE7-6: StumbVerter converts the NetStumbler text file and creates a map on-the-fly.
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Step 3: Converting to Mapping Format
The conversion process is the most difficult part of war drive mapping. There are so many dif- ferent mapping programs and, of course, they don’t all speak the same language.
This is where Microsoft MapPoint and StumbVerter make things simple. One program, StumbVerter, imports the Summary.txtfile and plots the APs on a map. See Figure 7-6 for StumbVerter in action.
If you don’t have the $300 MapPoint program, try searching at Netstumbler.com for a conver- sion tool for your mapping program. In the meantime, we’ll do a conversion using one of the best data manipulation programs available, Microsoft Excel.
The NetStumbler Summary format is a tab-delimited ASCII file. To read this file into Microsoft Excel, click File ➪Open. In the the Files of Type drop-down list, select the All Files option. This will show text files and more in the Open dialog. Select the Summary.txt file and click Open.
When Excel opens this type of file, it immediately starts the Text Import Wizard, as shown in Figure 7-7.
Choose the Delimited option and click Next. Make sure that Tab is the delimiter type. Click Next again, then click Finish. There is no need to specify data formats for each column.
Once your data is in Excel, it’s just a matter of deleting fields that aren’t needed, and formatting the data to work with your mapping software. See Figure 7-8 for an example of a stripped down spreadsheet.
FIGURE7-7: Microsoft Excel and the Text Import Wizard.
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NetStumbler export files use the letter format (N S E W) for compass direction. Some mapping programs do not read letters, instead using positive () and negative () signs. Positive is North or East, and negative is South or West. Use the “Replace” tool in Excel to replace “N” with “,”
“S” with “,” and so on. Be sure to replace the trailing space “Nspace” with the symbol
“” without a space to ensure success.
After deleting columns that aren’t needed, select File ➪Save As, and save the file with a differ- ent name in the proper text format. Some programs need comma delimited files, others may need tab delimited, and so on. The documentation or support site for your mapping program should have details on the suitable import format.
Step 4: Importing and Displaying in a Mapping Program
Mapping programs, in general, have an import function. This is helpful to add the addresses of points of interest, and of course, access point locations. A few different programs will be cov- ered here. Also, the manual import from Microsoft Excel will be performed using Microsoft MapPoint. (Surprise: They work really well together!)
Microsoft MapPoint Import Procedures
In Microsoft MapPoint, the import comes in the form of a “pushpin.” Extra detail on the loca- tion is stored in a text “balloon.” Figure 7-9 shows an example of the standard pushpin and a
FIGURE7-8: Microsoft Excel spreadsheet after cleaning up the data.
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text balloon showing details about a plotted wireless network. This concept of pushpins and balloons is followed by other applications, too.
MapPoint has some pretty sophisticated data visualization abilities. To get simple pushpins onto a map requires navigating through the maze of wizards and checkboxes. Other programs have simple import procedures (see below) but they don’t have the massive ability to show data in so many ways. See the section “Visualizing Extras” later in this chapter for an example.
Here are the steps to bring in a formatted text or Excel file:
1.Open Microsoft MapPoint and click Data ➪Import Data Wizard.
2.Change the Files of type field to the file type being imported. Find the file you want to import, and click Open.
3.The Import Data Wizard opens at this point. If prompted, make sure that the correct separation character is selected. The data should be separated into columns. If it looks garbled or hard to read, try a different separation character.
The tab character is the separation character (also known as a delimiter) used in NetStumbler export files.
FIGURE7-9: Microsoft MapPoint pushpin and text balloon.
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4.The wizard will now ask for column headings and data types. Change the automatic selections at this point. For example, set the SSID data type to “Name,” and change the SNR/Sig/Noise column to “Other Data.”
If you do not want the contents of a column to be displayed in the text balloon, select “Skip Column.” To have the data show up, assign it the value of Name, Name 2, or Other Data.
5.Click Finish to begin the import process. If there are a lot of APs, a progress bar will show the number of APs being plotted.
6.Next comes the Data Mapping Wizard. There is so much to this wizard, but we’ll just cover pushpins at this point. Select “Pushpin” and click Next.
7.Change the Pushpin set name as desired. Select a Symbol that suits your taste. Choose which fields should be displayed in the text balloons.
8.Click Finish, and you’re done.
The Data Mapping Wizard has many features and accesses some interesting stuff. Later in this chapter we will use it to plot signal strength using the Shaded Circle feature. It has nine differ-
FIGURE7-10: Microsoft MapPoint displaying APs after a war drive.
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FIGURE7-11: The popular StumbVerter program plots in its own window.
ent ways to display data: shaded area, shaded circle, multiple symbol, pie chart, sized pie chart, column chart, series column chart, and everyone’s favorite, the pushpin. Also, with MapPoint’s built-in demographic data, you can spend hours viewing the strange habits of your neighbors, such as “Adults who use sore throat products” as viewed by state, Zip code, or census tract.
Sometimes while war driving, the GPS will conk out, get disconnected, and so on. If that hap- pens, you may record an AP with the latitude and longitude of N 0.0 by E 0.0. MapPoint will happily plot that and expand the map to show those APs off the coast of Africa at 0 degrees latitude by 0 degrees longitude. When plotting these sources, you can delete them, or ignore them. If you war drive the same access point at a later time, the coordinates will be updated.
See Figure 7-10 for a map created by MapPoint using a text file import.
Microsoft MapPoint Using StumbVerter
StumbVerteris a free program that converts files from NetStumbler format into Microsoft MapPoint format (see Figure 7-11). The unique feature of StumbVerter is that it uses Microsoft’s common object model (COM) programming interface to work directly with the MapPoint map data. The practical upshot is that you do not need to import into MapPoint.
StumbVerter does it all automatically.
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Follow these steps to begin working with StumbVerter:
1.Download StumbVerter from www.sonar-security.comand install it onto your sys- tem. (Note that you need MapPoint installed before you can use StumbVerter.)
2.Run StumbVerter and select the down arrow next to the Map button to choose “Create New North America.”
3.Now click the down arrow next to the Import button to select NetStumbler Summary.
4.Open the file previously exported from NetStumbler. Progress is shown during loading and drawing the map. Be patient if there is a lot of data.
That’s it! StumbVerter is practically automatic. There are also a lot of features with filtering, signal strength, and a sweet antenna comparison tool called ACT. Experiment with StumbVerter to get the most out of it.
If you feel inclined, send donations to the programmers of StumbVerter. Much effort is expended putting the program together and making it available for free.
FIGURE7-12: The WiMap program has several options.
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