Why do I get obviously wrong locations from IP addresses?

In this excerpt from
Answercast #19, I look at the vagaries of IP address mapping and show how
it can often go wrong.

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Where are you really?

Location on the internet is really a mystical and occasionally scary thing. It’s notoriously inaccurate. For example, depending on which service you use to find the location associated with my static IP address here at home, you may find that I’m in Woodinville. Occasionally it’s actually fairly close. You may find that I’m in Seattle; you may find that I’m in Portland. I’ve had at least one person or one service locate that IP address as being somewhere in California.

IP address location, as I said, with publicly available information is notoriously unreliable.

Targeted marketing

Now obviously, that doesn’t stop some services from using it. Very often we will see ads that are targeted to specifically where you’re at. But by and large, what you’re seeing is not really unexpected at all.

Google router mapping

Now, there’s one interesting scenario that actually can explain this kind of thing, and we have to step away from IP addressing for a moment and start talking about your wireless router.

Some time ago (or maybe it’s ongoing… you may remember), there was a part of Google’s street view operation where they went around and took pictures of all of the streets, and so forth, that you’ll find on Google Maps.

They were also keeping an eye open for which wireless routers were visible at those locations as they drove around and they kept that. What that allowed them to do, based on this database of wireless access points and where they all exist physically, is use that information as well to help determine your location.

For example, since every wireless access point (like any network connected device) is supposed to have its own unique MAC address, what they came up with was a database of MAC addresses and locations.

Now things get weird when the router moves. So, let’s say that your roommate used to live in New Jersey and in fact, lived in New Jersey when Google was doing this mapping in that area. He had his router on in New Jersey as the mapping took place. Google now thinks that router, the MAC address associated with that router, is now somewhere in New Jersey.

Then you moved; you moved to say Albany. Google doesn’t really have a way to update the location. There’s a lag between the time you moved the router and the time the mapping is updated to reflect that the router is moved. So sometimes, it’s a reflection of where a particular wireless router used to live.

In fact, what’s really interesting is that this doesn’t necessarily have to be your router. It can be some other router in the area that happens to have previously lived in New Jersey, that has since moved to Albany, that somehow is causing the location to get off kilter.

Have you been hacked?

So, the short answer is no. You haven’t been hacked.

There’s nothing wrong with this scenario at all; it’s actually very, very common. Trying to determine physical location from internet based information, such as Wi-Fi access points and IP addressing, is notoriously inaccurate.

What you’re seeing doesn’t surprise me in the least.