People who have jailbroken their iPhones in order to get tethering for free have started receiving notes from AT&T:
Our records show that you use this capability, but are not subscribed to our tethering plan.
and
If we don’t hear from you, we’ll plan to automatically enroll you into DataPro 4GB afterMarch 27, 2011. The new plan – whether you sign up on your own or we automatically enroll you – will replace your current smartphone data plan, including if you are on an unlimited data plan.
In no way do I see this as a bad thing. Anyone that’s self-righteous enough hack their iPhone while still under contract and steal data via a means that they aren’t paying for should be punished. AT&T isn’t saying that they will back-charge you for previous months, just that if you continue, they will charge you appropriately by auto-enrolling you into the tethering plan.
A random Internet commenter argues:
This is bogus. Their data plan is UNLIMITED!!! This means that, i gould download 100TB of data a month on my phone and it still fits in the plan. If this is not the case the term unlimited does not apply and it’s false advertising. Tethering is using a data plan on a phone to link other devices. THE SAME PLAN! The fact that phone companies can get away with double billing their customers is rediculous. three words-class action lawsuit. bury them in litigation. If I’m stuck paying $30/mo for a data plan that isn’t even as fast as my home network, I better damn well get unlimited everything on it.
Being tech savvy doesn’t allow you to circumvent a carrier’s billing system. If AT&T intended for you to use 100 terabytes of data a month via their 3G service, they would say so. Even before AT&T removed “unlimited data”, you would still get a phone call from them if you exceed something like 5-15 gigabytes a month. I believe Verizon’s unlimited plan as far back as 1998 was still restricted to 5 gigabytes of transfer both ways including tethering. It’s only recently that carriers have began to enforce it.
Data usage like that does in fact cause degradation to the network. Have you ever been in a coffee shop and the guy next to you was pushing Pandora+YouTube HD+FTP Uploads while you could barely retrieve a single web page? Do you remember the anger you felt? Bandwidth restrictions by mobile carriers are meant to keep us from feeling that pain and I don’t think the usage restrictions are that terrible. They may grow more painful over time but, now, they’re manageable.
These limits aren’t going away. Stop hacking and deal with it.