How would you track customer smart phones without some sort of overall network management? How else would you get the nodes signal strength and other metrics in real time so you can locate the device? If you're talking about geolocation on the client side, that's completely different than what this article is talking about.
I was tackling a slightly different problem, so yes I was trying to do things client side.
we were seeing 2 - 3 meter positioning for normal cell phones in a large open area with 4 Wifi nodes available, with 3 - 5m in a more typical office environment with 4 - 5 nodes.
This is inline pretty much with what I was getting. 15-20ft being 4-6m.
The reason I was talking about unmanaged networks, was because the original poster was talking about Google aggregating information from arbitrary locations to make determinations on the user. If a department store wants to implement a system to track it's users in a store, they can do that pretty well for what their needs are. I was talking about Google trying to aggregate location data from places where equipment was not necessarily deployed with tracking in mind. For example, starbucks could probably give 2 sh!ts where you were in the cafe. If google got a hold of the data of you while at starbucks, they would be in the same position I was referring to.. They have signal strength readings of various APs that they have no idea where they were deployed, how they were deployed, etc. That's a different scenario then if Starbucks were to deploy a purpose-built location tracking system, and then forward the information to Google.
By the way, I tested some server side commercial solutions, but I ran into some interesting scenarios, but maybe it's because the environments I was dealing with have less constrained environments. For example, in our own workspace each office space is not identical, nor is there any pattern to the layouts, as it's the employees choice on the layout. That means we ran into problems even with the commercial solutions, based on how the device was placed. Some people placed the phone on the desk next to keyboard. Some placed it in pocket. Some placed it in jacket pocket. Some placed it behind their monitor out of the way of their work area. Some put it in their flipper cabinet. Due to all this, we were never able to reliably get accuracy below 15ft. Depending on the problem you are trying to solve, that is probably good enough.
But one scenario I tested, involved a restaurant. Even with granularity down to 6ft... That wasn't good enough to differentiate someone sitting at the same table as you from someone sitting at the table next to you, because sometimes the person sitting in the chair in the next table over, is actually closer to you then the person sitting across from you at your own table.
Are you that crappy at your job? They use more than one radio (usually SDR so they can simultaneously track BT and GSM), and stores are pre calibrated to map coverage and propagation.
In case you didn't read the original article, the technology in question only looks at wifi beacon packets, it doesn't track anything else from the device. That's why I used the specific research examples that I did. In fact, if you actually read my arguments, I was saying you needed to have other sensor inputs to make the results more accurate.
> the AP
Where did I say I only looked at situations with a single AP?
"Don't discount flying pigs before you have good air defense." -- jvh@clinet.FI