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Wrong Number: Why Phone Companies Overcharge For Data
MrSeb writes "A recent study (PDF) 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. 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."
DNS requests, which are not counted by the carriers as data usage.
I'd love to see a source for this.
Well, a source to anything actually, but it seems to much to ask around here these days...
Well I sent a check for my monthly bill... not my fault you didn't receive it.
Here's the paper: http://www.cs.ucla.edu/~chunyip/publications/mobicom12-peng-accounting.pdf
I guess that means the operators will shortly release an update for the phone OS's to also charge for the data the phone sent but wasn't received by the operator.
1. write an app that disguises streaming porn as a DNS request
2. ???
3. Profit!
Thank you for your suggestion. at&t(R) is committed(tm) to rebuilding the nation's largest 4G network this year with your input. To pay for the buildout* you will notice a 10% 2012 Nation's Largest 4G Network Improvements Fee along with a 200% SMS price increase. Thank you again for choosing at&t(R), with the nation's largest 4G network.
*Buildout subject to cancellation without notice. Just kidding about that last part, we cancelled it while you were reading that sentence. The fee stands to pay for the costs of typing the prior two and commissioning a forthcoming Gartner study to validate their market impact.
You can hold down the "B" button for continuous firing.
To get rid of the taste of the food.
Resending a packet due to a missed ACK takes up air time, just like it did sending it the first time, and the carriers have no control on where the user will be. If they make their systems robust enough to move their present average packet reception rate from an already-good 93-95% to, say, 99%, this will only enable their users to move down another floor in their sub-basements, or another few city blocks, or another cubicle row deeper into the building, before the average goes back down again -- after all, wireless systems have limited range. The cost of the new infrastructure would be roughly twice that of the previous one ("increasing coverage is increasingly expensive"), and you're going to pay for the cost of the infrastructure either way in your air-time charges.
Look at it this way: Even if the company only charged for packets successfully received, it would just increase their rates by (1/0.95) - 1 = 5.3% to (1/0.93) - 1 = 7.5% to maintain the same cash flow. Plus it would have to start keeping track of the success or failure of each packet transmitted, and put that into its billing scheme. That's a database PITA I don't want, thank you very much.
* Android Droidstats usage logger: 369 MB (2012-07-31 22:16h)
* Android "My Data Manager": 337 MB (2012-07-31 22:16h)
* Vodafone online usage monitor: 307 MB (up to 2012-07-30 17:46h)
* Phone bill for July: 343 MB (since a couple of months they actually mention the total; before I needed to use a perl script to parse the PDF invoice and add the data usage of some 200 separate data sessions)
When I asked about the differences a few months ago, the Vodafone customer service told me: "The information on your Vodafone account online is the real usage. Numbers from data usage apps are not reliable." But I highly doubt that I used 36 MB over the last day of the month, so it seems that within Vodafone they have different systems.
My train commute (where I use most of my data) passes through an area with bad coverage, so I would have expected a bigger difference based on the theory that packet loss accounts for most of the difference.
Avantslash: low-bandwidth mobile slashdot.
"Overcharged". What a sweet word to use instead of other words like fraudulently charged or stolen. No, you were simply "overcharged". Don't worry about it. And your bill is due by the 1st.
Seven puppies were harmed during the making of this post.
Data takes up network capacity whether the device receives it or not.
if you're an operator..
step 1. hire some flooders.
step 2. profit.
essentially this is why they should sell by speed, not by usage.
world was created 5 seconds before this post as it is.
The nature of TCP includes positive acknowldgement and retransmission. If you don't get that acknowledgement, don't charge the user for that packet.
Give me Classic Slashdot or give me death!
Do you really think what carriers charge is how much it actually costs to send a text message?
step 1. hire some flooders.
While I don't expect legit carriers to crap-flood for profit, it seems this presents a perverse economic incentive not to invest in improving the quality of their networks.
It's only gone from the big carriers. I use Metro PCS, and have 4G in the city where I live, along the major route I commute to Atlanta, and of course have it in Atlanta itself. (The trade off is having text-only outside of the network.) If you live in a rural area and need one of the big guys to provide coverage, you're screwed, but if you live in a metro area, you'll probably get a better deal with a smaller regional carrier.
Occasionally living proof of the Ballmer peak.
All I need to do is run a website or service on UDP/53 and mobile users wont ever get charged? It can't be that easy.
Another thing is, you could attempt to download far more data than your connection is capable of. For example, making a portable device participant in a BitTorrent network, where the client intentionally attempts to download as much data as possible -- at a high loss rate, the data your phone isn't capable of receiving still gets sent by the tower, and therefore still congests the wireless portion of their network, but your device never receives the data, because it's not capable of it.
Packet loss is an end-to-end connectivity thing; it is no specific party's responsibility. Ultimately, the end user has to take responsibility for requesting packets that they are unable to receive.
It would probably be better if the phones warned the user about high packet loss or implemented a temporary self-shutoff or backoff. And wireless providers offered SLA credits, for data discarded before it's even attempted sent by the provider's radio towards the user's phone (e.g. Output discards).
Otherwise, packet loss by the phone itself, or loss of radio transmission, is a result of network congestion. There actually is very good sense in the user having to pay as if data was received when they are requesting packets that are being lost due to congestion --- the user is participating in the congestion that should be prompting the network provider to upgrade the network in that area, so they should pay more for causing that congestion.
The providers should just clarify that dropped packets do count, and choose appropriate pricing.