XPost: misc.phone.mobile.iphone   
   From: marianjones@helpfulpeople.com   
      
   Jeff Liebermann wrote:   
   >>The question mainly is WHY Apple stores them to the number of integers that   
   >>they do, where all I can do is convert the integer values to human-readable   
   >>decimal coordinates.   
   >   
   > If you look at the original data you posted a few articles back, you   
   > might notice that the number of significant digits in the Lat/Long   
   > numbers vary widely for each BSSID.   
   > That implies that the number is   
   > coming from the GPS receiver and is probably not "processed" prior to   
   > be being logged.  The entries with fairly few significant figures is   
   > probably an old GPS who's designers were only confident in a few   
   > digits precision.  The longer entries could easily be the output of an   
   > RTK differential GPS system capable of millimeter accuracy.  A way to   
   > verify this is to write a program that grabs the first half of the   
   > BSSID and searches various OUI databases for the name of the   
   > manufacturer.  Something like this:   
   > "Wi-Fi Vendor - Detect vendor of a Wi-Fi access point with just your   
   > iPhone or iPad"   
   >    
   >   
   > I'll try it.   
   >   BSSID: 84:eb:3e:f8:36:d3   
   >   Latitude: 32.45880508   
   >   Longitude: -93.81717681   
   > Plugging the BSSID into:   
   >    
   >    
   > I get:   
   >   Vivint Smart Home	84:eb:3e:00:00:00/24   
   >   
   > Here's a longer Lat:   
   >   BSSID: bc:9b:68:7e:15:c3   
   >   Latitude: 32.459438320000004   
   >   Longitude: -93.817276   
   >    
   > I get:   
   >   Vantiva USA LLC	bc:9b:68:00:00:00/24   
   >   
   > I can't determine if either company has a reason to have a longer   
   > Lat/Long.  However, notice the number of digits in the Lat, which are   
   > mostly zeros, except for the last digit:   
   >   Latitude: 32.459438320000004   
   > I don't know what they're doing, but it looks like they're using the   
   > Latitude to store some kind of data or ID.  There are several other   
   > entries in the data that show a similar pattern of 8 places to the   
   > right of the decimal point for useful data followed by 6 zeros and 1   
   > numeric digit.   
   >   
   > This should be useful:   
   > "Accuracy of Decimal Places in Latitude and Longitude Degrees"   
   >    
   >   
   > 8 decimal places is 1.11mm resolution which is probably the limit of   
   > GPS resolution (not sure).   
   >   
   > Anyway, good luck with whatever you're doing.   
      
   Thanks Jeff. We're neighbors in the Santa Cruz Mountains, by the way.   
      
   You've taught me a lot over the years, one item of which is that most   
   consumer routers (e.g., those with Broadcom chipsets) can't change the   
   outward facing BSSID (although some professional routers certainly can).   
      
   I have plenty of old Surfnet, Etheric, Hilltop & Ridge equipment, that I   
   repurpose them as access points even though they're designed for CPE use.   
        
        
        
      
   Loren and Mike, in particular, and sometimes Andrea Lovelady at Surnet,   
   give me all their old transceivers which I repurpose as access points   
   (although much of the old Surfnet stuff is licensed Mikrotik stuff).   
      
   I'm well aware you're an old hand at UNDERSTANDING what WISPs can do!   
   So I appreciate that you looked up the brand of each of the strange ones.   
      
   My main goal here is simply to UNDERSTAND how Apple's WPS database is   
   completely different than everyone else's, where I'm in discussions   
   with Brian Krebs and the Mozilla research team (Dan Veditz) so   
   I'm aware how the morally responsible companies handle hidden SSIDs.   
      
   Fundamentally, the results from Apple's RADAR bug report is that following   
   Apple's public legally binding privacy policy will NOT work.   
      
   You have to know the super-secret trick to stay out of Apple's WPS   
   database, and even then, that trick puts you into every other one.   
      
   Yes. You of all people understand the catch 22 that Apple puts us in.   
      
   My main goal is simply to get Apple to do the morally right, ethically   
   correct, and legally defensible thing - which I have so far failed at.   
      
   But I rarely fail for long as you can note by the PG&E lines NOT failing   
   anymore as PG&E has to call a conference3 with me for an hour EVERY SINGLE   
   TIME the power goes out (as per my CPUC complaint resolution).   
      
   So I rarely fail.   
   But so far, I'm failing to get Apple to do the right thing.   
   Even though I'm communicating at the highest (VP) level at Apple.   
      
   However, time (and effort) will tell.   
   Then I will be successful.   
      
   And that will preserve the privacy of hundreds of millions of homes.   
   Which is what drives me after all.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)