Everyone is all aflutter about the news that Steve Jobs knows where you have been. Since that Earth-shattering bit of news, a lot of bloggers and reporters have pointed out how other software within the iPhone can do the same thing without the user realizing it, and how the Android devices do this as well. Greg Laden has a good summary of these articles in his post iKnowwhatyoudidlastsummer.

To be blunt, people being tracked in their everyday lives is nothing particularly new. I'm happy that this has made a splash in the mass media since it's a situation that has been increasing in prevalence without major notice until now. When I teach IT security, I always spend some time covering privacy issues as well, and have discussed tracking issues regularly for fifteen years now.

A common thought problem I would often give to my students is to plan a cross country road trip in such a way that they could not be tracked. Fifteen years ago this was an interesting problem that forced people to think about how they interacted with a variety of databases. Today, it's a more difficult proposition to even accomplish.

Even before the advent of modern smart phones, people have been automatically tracked. When you use your debit or credit card, the bank has a primitive tracking record of your movements. The more you use it, the better the tracking. So, before leaving on a hypothetical un-tracked trip, you need to remember to leave these cards at home. You will need to work with cash. If you don't want to tip your bank off to your trip, you need to collect the cash in advance, a little at a time. It may also be a good idea to give your cards to a trusted friend so there is local activity on them while you are away, electronically geo-tagging you to your home town.

You can't just leave your smart phone at home; you will need to leave any cell phone behind. Cell phones have been tracked since the very first cell phone. Cell phones work by having the towers (and thus cell companies) track the phones. When you first turn on your phone, it sends a message out. Any nearby towers receive that signal, which then talk to a computer at the company. The tower with the strongest signal (as well as reasonably bandwidth, consistent signal, and other factors) will be granted sole authority over your phone. This process is periodically repeated in case you move. The cell company must always know which tower to direct a call through to get to your phone.

Ten years ago the cell companies swore to us on a stack of their own quarterly reports that this tracking data was not stored in any reasonably permanent way due to the amount of data and cost of storage. I haven't heard much about this as the cost of storage has plummeted, but I was always leery of the argument since it was based upon no compression of data that is easily compressed anyway. After 9/11 there was a lot of discussion about phone companies not destroying data that had been previously been destroyed. The problem now, of course, is finding out what data is actually stored today since that information is considered national security.

The difference with a modern smart phone is the introduction of a GPS chip that can provide better accuracy of your location. Still, accuracy of tower-only location services has gotten so good that several years ago governments began requiring cell phone companies to upgrade all of their towers so they can triangulate your position (using signals from multiple towers) to better coordinate emergency response when you call 911. While this works great when you get into an accident and want the government to find you, but it also means you can be tracked at all times to a surprising level of accuracy.

So, you will need to stop your phone from even communicating with a cell tower even if it's not a smart GPS-enabled phone. You can turn it off, but I never trust computers that have to monitor for a key press to be truly "off". You can remove the battery (assuming that's an easy thing to do). You could tightly wrap the phone in aluminum foil, then drop it in a Mylar bag. Or, I suppose, you could drop it in a river and walk away, which is probably the most satisfying way to stop a cell phone from tracking you.

Now, ready for your trip? Not quite yet.

Does your car have a tracking device and cell phone secretly stashed away behind a door panel? If it does, it may not mean you have an enemy agent in a black helicopter tracking your every move, it may just mean you have OnStar, or a similar system, installed by the auto manufacturer. That system is, basically, a tracking device attached to a cell phone integrated with your car's computer system. You should be able to locate the fuse which powers that module and remove it, or, if you are really paranoid, dismantle the panel it's mounted under and chuck it into the same river as your cell phone.

Now it's time to plan your route, and this is where things get complex.

If you live in a major city, especially Chicago or London, it can be difficult to find a route out of town where your license plate will not be recorded as you pass through an intersection. Many early red-light cameras would only take pictures when triggered by sensors, yet simple observation shows that such sensors are often triggered even when no one is running a light, such as when people turn right on red, or go over a sensor when turning left. In addition to that, many intersections now have cameras that simply record all traffic flow at all times. You need to avoid all such intersections.

The camera problem is made worse by projects such as the Chicago OEMC initiative which links private cameras into the Chicago Office of Emergency Management and Communications system for recording and monitoring. Even if you trust that your local 7-11 will destroy its security recordings, those same recordings may be saved by the government automatically.

On your trip toll roads, obviously, are a very bad idea. Even if you threw your toll authority Radio Frequency ID transceiver into the same river after your cell phone, cameras record every license plate passing through every toll plaza. By the way, if you ever want to prove your spouse was cheating on you, or they are a bad parent by working too late, you can subpoena their toll records for evidence.

Off the toll ways (and major expressways which may have traffic cameras, though the older systems don't have the resolution for picking up license plates), you need to be careful about any city, town or county you pass through with cameras. They are now so prevalent, you most likely need to do scouting trips to find a clear route.

Once you have arrived, you may be able to walk around anonymously for now. If it's in a big city, you can leave your car somewhere (Where? That's another problem) and use taxis. At the moment you don't really have to worry about automatic facial identification too much. While the technology is certainly impressive, unless someone has a good picture of your face and is specifically looking for you, such system won't be a help. They can find matches for specific people, but, as of yet, can't just identify all people passing in front of them.

One last piece of advice is to make sure you don't use your supermarket loyalty card when buying an apple in your destination city. Of course loyalty cards are a whole new privacy problem in themselves.

Ready for the return trip or do you just want to follow your cell phone into the river?