The next time you get your smartphone bill, you might want to double check your data usage.

A recent study conducted by UCLA professor Chunyi Peng shows that carriers generally count data usage correctly, but those customers who commonly use their device in areas with weak signal strength or to stream audio or video are often overcharged. Peng and three other researchers used data gleaned from an app installed on Android smartphones on two different carriers.

The issue appears to be in how the system is set up to count data usage. Under the current scenario, data is charged as it is sent from the carrier’s network to the end user. What does not exist is a system to confirm whether the packets are received, and thus preventing charges for unreceived data.

Peng demonstrated this in two extreme circumstances. In one case, 450 megabytes of data was charged to an account where not a single bit of it had been received. On the flipside, Peng’s group was able to construct an app which disguised data transfers as DNS requests, which are not counted by the carriers as data usage. Here they were able to transfer 200 megabytes of data without being charged.

“The root causes lie in lack of both coordination between the charging system and the end device, and prudent policy enforcement by certain operators,” Peng writes [PDF]. She declined to name the two providers targeted in the test, only offering they serve half of the current US wireless population.

Overall, the average overcharge is about 5-7% for most users. While that does not seem like much, with unlimited plans gone and data caps in style that could pose potential problems for some heavy data users. Could you be going over your data allotment based on data you never received? It’s quite possible.

Considering the carriers charge as much as $15 if not more for every gigabyte you go over your plan, that can become a big deal very quickly.

Peng suggests that a system to confirm receipt of mobile data packets is sorely needed. “We believe that the network has to take more central role in the charging process, while the end devices offer useful hints and feedback to the network. The network naturally has ‘centralized’ views on users and ﬂows, and more resources to control and regulate the charging decision,” she concludes.

What can you do in the meantime? Unfortunately, it means being mindful of your data use even more. Don’t use data frequently in areas with poor signal, and cut down on the amount of streaming audio and video if you can. That’s about the only thing you can do right now while we wait for the carriers to fix the issue.

A better system needs to be put in place, and in this day of data caps a confirmation we’re actually receiving the data we pay for is something that we should expect. Nobody should be paying for data they’re not using, especially if there is a simple fix available to solve the problem. While the carriers might argue that they incur costs whether or not we receive the data, in the end it’s typically no fault of ours that we don’t — it’s their poor coverage — so it’s not really fair to expect us to pay for it.

What say you, cell phone companies?

[Photo credit]

[Photo credit]