How can I use a MAC address to get a GPS coordinate?

Question

I know services exist such as skyhook, but I simply can not find an API or information on how to use it. I have a list of MAC addresses from wireless networks, or even wired networks, and I want to get triangulated GPS coordinates of the user.

EDIT: Somebody mentioned that you can't get MAC address information? From Windows 7 I did "netsh wlan show networks mode=bssid" and I see the below. I assume the address in BSSID is static and at least correlates?

SSID 6 : linksys
Network type            : Infrastructure
Authentication          : WPA-Personal
Encryption              : TKIP
BSSID 1                 : 00:0c:41:19:56:7b
     Signal             : 15%
     Radio type         : 802.11g
     Channel            : 6
     Basic rates (Mbps) : 1 2 5.5 11
     Other rates (Mbps) : 6 9 12 18 24 36 48 54

SSID 7 : KSJ
Network type            : Infrastructure
Authentication          : Open
Encryption              : WEP
BSSID 1                 : 00:18:01:95:e7:ca
     Signal             : 30%
     Radio type         : 802.11g
     Channel            : 2
     Basic rates (Mbps) : 1 2 5.5 11
     Other rates (Mbps) : 6 9 12 18 22 24 36 48 54

SSID 8 : benchhome
Network type            : Infrastructure
Authentication          : WPA-Personal
Encryption              : TKIP
BSSID 1                 : 00:0f:b5:e3:2e:24
     Signal             : 23%
     Radio type         : 802.11g
     Channel            : 11
     Basic rates (Mbps) : 1 2 5.5 11
     Other rates (Mbps) : 6 9 12 18 24 36 48 54

Answer 1

You would have to resolve the MAC address to an IP address, and then do a host lookup on the IP address. (This will tell you the ISP that the user is connected under) Its unlikely that you'll get an accurate location out of this. However you may be able to identify the country and/or city that the MAC address is currently residing in.

With the IP address you may want to use a service/database such as GeoIP to get some geographical information on the IP address. For the ISP location, you'll need to find a database of the locations of the ISPs.

I took a look at SkyHook's site: This is how they do what they do:

1. WiFi Access Points: Many WIFI points don't change, so this helps narrow down where a user might be.
2. Cell phone towers, these are at known locations, and with 3 points or more you can triangulate a very accurate location of a user, with singal strengths.

Microsoft also has a feature similar to this with VirtualEarth

Answer 2

For the record, unless you are parked on the same subnet as the MAC address and have an active connection -- i.e., you received an IP address from the access point -- there is no way to determine a Wi-Fi AP's IPv4 address without external factors (even with MAC address in hand). I'm curious how steven suggests that you resolve it (since it doesn't sound like you're connecting to these networks). And no, ARP won't help you here.

Worth thinking about also is a Wi-Fi AP that identifies itself with a RFC 1918 address. My AP has an IP address of 192.168.250.1, and has its own default gateway upstream -- what will the geolocation for the IP on my AP give?

---

Every wireless access point identifies itself with a MAC address free and clear. SkyHook uses the broadcast MAC addresses and a database of known MACs against street addresses to triangulate where a person is.

The reason SkyHook works at the MAC/street address level is because GeoIP services are inherently useless. My employer has a /20 allocated by RIPE, which is announced from London; because my employer is a United States company, almost every GeoIP service locates these IP addresses in New Jersey. I'm amazed there are few GeoIP systems that bother to check the announcing ASN, but I digress...

That said, SkyHook combines known Wi-Fi AP MAC addresses (no IPv4) with cellular triangulation to get pretty darned accurate. According to SkyHook themselves, it appears the database is powered mostly by user submissions of APs. According to the submit AP page, they work on MAC addresses:

[...] or to learn what a MAC address is and how to get it, visit the Skyhook Support site.

It seems the biggest boon of their service is the database of access points. You do not need to do GeoIP at all, you just need the data that they have. A hole in the market for an open source project, I gather?

Answer 3

The Skyhook system seems to work only for mobile devices. It uses either GPS (from the device's own GPS software), knowledge of the location of the WiFi access point in use, or triangulation from the cell towers that are in use.

Details are here.

The best accuracy comes if the user is willing to share their GPS location, or their WiFi access point is listed in the Skyhook database. However, most casual users won't have their GPS antenna turned on unless they're navigating somewhere, and most private or corporate WiFi access points won't be listed.

So in practice this service is only really useful for applications where the user gives consent, such as tracking devices in use by a company.

The fallback is to use geolocation of the IP, which as I mentioned in my comment above is very very inaccurate and is really only of use for fun.