Every month, US telcos calculate how much data customers have crunched through on their phones and charges them accordingly. But a new study suggests that telcos might not be adding things up quite right.
Technology Review reports that computer scientists at University of California, Los Angeles, have been probing the systems used by "two large US cell-phone networks" -- no names are named -- to assess how accurately they calculate data usage. Using data-logging software, the team kept tabs on how the carrier's calculations squared up with their own.
They found that, while carriers often get the calculations right, they often over count. In particular the team found that over counting seemed to happen most when using applications that stream video or audio, or when coverage was weak or unreliable.
The problems is down to the fact that carriers count data that leaves their network, and not what's received by your phone. Obviously, the two don't always match.
While the effect isn't huge, with typical discrepancies being somewhere between 5 and 7 per cent, that's definitely enough to accidentally nudge you over your monthly data allowance. With AT&T and Verizon both charging $US15 for straying into each new gigabyte of data over and above your cap, it could even be costing customers real money.
The solution, of course, would be to tweak the measurement systems so that they count how much data actually makes it to the phone. Whether that's ever going to happen, though, is a completely different story. [Technology Review]