An unexpectedly large mobile bill is never a happy sight (unless you hate money), but at least you can consult your call records or contact your provider and get some idea of what’s responsible. But what if you were accruing mysterious data charges for bits you know you didn’t receive? Well, chances are if you have consistently bad reception, it’s possible you are copping a little extra on your bill.
A research paper by Chunyi Peng et al. from August this year, entitled “Can We Pay for What We Get in 3G Data Access?”, highlights a weakness in current mobile networks were the provider will transmit data to the customer, but does not (or cannot) acknowledge if that data ever arrived. As a result, if you’re stuck with a bad signal or find yourself in a congested area, you could be charged for data you never receive.
The paper details several tests the researchers conducted on “two major” US networks, with the most extreme case seeing charges for three hours and 450MB of usage, none of which was successfully delivered.
Ben Grubb over at the Sydney Morning Herald got in touch with Telstra, Optus and Vodafone to find out how these providers deal with the issue — if at all. Telstra stated it has “protocols” in place to detect and handle cases where data never arrives, but was reluctant to guarantee they were always effective, while Optus and Vodafone representatives said they had no definitive way of managing the issue.
That said, Vodafone did state that these charges would be minor and could not amount into “any form of bill shock”.
Chunyi Peng’s paper suggests the solution is a “coordinated charging system” where the network and end system both play a part in data delivery — essentially your device would send some sort of confirmation to the network upon receipt of the data (beyond the fundamental requirements of TCP).
It’s described as a “promising” way of handling the problem, but could the likes of Telstra, Optus and Vodafone deal with the additional overhead of these confirmation packets? What’s to stop hackers from preventing said packets from being sent from the receiving device, or perhaps throttling their delivery to prevent providers from getting suspicious? What about streaming multimedia or gaming services that have never relied on guaranteed packet delivery (UDP) for performance reasons?
Sure, the infrastructure in place now isn’t perfect, but it’s going to take some planning to make a more robust — and fair — system work.