Tuesday, May 10, 2011

Jailbroken iPhone Unauthorised Tethering: How AT&T Tracks

Now some of the iPhone jailbreak brigade likes to enjoy tethering their jailbroken iOS smartphone and avoiding forking out for an upgraded tethering plan, but AT&T sent out SMS messages and emails letting their customers know if said customer continue to tether they would be charged for it.

So how does AT&T keep track of who is going the unauthorised tether route with their jailbroken iPhone? Well according to an article over on Maclife, by way of Redmond Pie, the guys over at Android Police have apparently discovered how AT&T can track customer’s tethering.

Here’s what the Android Police article says… “Jailbroken iPhones typically use the same tethering technique as a standard iPhone, the one that’s already present in iOS. This method exposes tethering activity quite readily, because the iPhone, when in tethering mode, sends traffic through an alternate APN (AT&T access point/router) for the express purpose of identifying the traffic as tethered data. This makes it extremely easy for AT&T to identify whether or not an iOS device is utilizing tethering, and just how much of their data is consumed via tethering.

Some tethering applications for iOS make use of alternative methods and route tethered traffic through the phone’s normal data APN, but by and large, most jailbreakers stick with the stock application because it’s easy to use and doesn’t require any complicated setup. In fact, many iPhone users jailbreak for the sole purpose of avoiding AT&T’s tethering fees (for why, see next section). These are the people AT&T’s is going after.”

Apparently one of the popular jailbreak-apps for tethering is MyWi, which apparently exposed the users activity to AT&T and will probably result in AT&T getting in contact so the user can get official tethering. However word is there is another app that AT&T can’t track called PdaNet, which is available from Cydia.

So there you go, how AT&T tracks unauthorised tethering on jailbroken iPhones and an app on how to avoid getting caught…feel free to let us know if you decide to use the PdaNet app from now on.