Unknown data usage early morning

On a recent data usage problem that I encountered during the last 10 days. Perhaps one problem can be caused with email accounts accessing imap servers.

More: https://discussions.apple.com/thread/3944408

snolan wrote:
If that application has location services enabled, or periodically reloads it's data from the internet, or trickles in new advertising because it's a free ad-supported application - you will continue consuming battery power and network usage.

If your screen is locked, your WiFi connection becomes unavailable, which means that the increased network usage is carried by the 3G network and consumes your data plan even though you are powering up next to your WiFi base station.

The temporary fix is to take the time to learn how iPhone multi-tasking works and shut down any unneeded applications that are running:

• double tap the home button to bring up the task bar
• press and hold any application that is running but you no longer want to be running
• then press the minus sign on that application to actually stop it from running
• target any streaming, location aware, and advertising supported applications first

MBBM wrote:

I received a message about nearing my limit also. This amazes me because most of the time (all the time at night) my devices are using the wifi signal at my house. I'm going to start turning my phone off when I go to sleep. This is ridiculous.

You haven't read the thread you posted to (not surprising, considering how long it is). But you are mistaken on two points (which are discussed extensively in the thread):

1. The data transfer that appears on your bill at night was not transferred at the time it is stamped on the bill. That is the time accumulated data collected by switches throughout the day is reported to the billing system.
2. The phone does not use WiFi when it is asleep. Any data transfers when the phone is not active (meaning with the screen lighted) goes over the cellular network. WiFi is turned off when the phone is asleep to conserve battery.

I can understand why you didn't read 89 pages, so let me summarize it for you:

• The timestamp on the bill is NOT the time that the data transfer actually occurred. It is the sum of data over the day from one reporting station. There is more than one entry per day because data usage is recorded by different reporting stations on the network.
• If the phone is asleep WiFi is OFF, even if you are near an access point (to save battery, because WiFi uses power continuously when it is on unlike 3G which only uses power when data transferes are actually occurring.)
• What you must do is track data as recorded on your phone (settings/general/usage). Reset it at the beginning of each billing period so you can see if AT&T is charging you for data the phone did not use.
• To find out when data transfers actually occurred there is an app called Dataman that tracks data usage b time of day and location. It increases battery drain, however.

I'm in Ireland using Vodafone Ireland. I added a third gmail account to my iPhone on Thursday last and noticed the following, all data is overnight as confirmed by Vodafone:

1. Thursday .2 GB of data used
2. Friday 1.2 GB of data used
3. Saturday 1.8 GB of data used

I'm awaiting Sunday, I should have that tomorrow. Why adding a gmail (imap account with 5 emails in it) can lead this amount of traffic. Can a 3G data network really traffic 1.8GB of data?? I'm at a loss. I've disabled data and will perform a full restore of the iPhone. This is the second time this has happened over the last 12 months.

::sigh:: Do people always post to message threads without even scanning the posts first?

1. The large data transfers are not large data transfers. The are the accumulated data transfers over a period of time.
2. They do not occur at the time shown on the bill. That is the time the accumulated data transfers were posted to the billing system.
3. The accumulated total is arbitrarily shown as "sent", however, the total includes both sent and received.

It's important to understand this so you can figure out what caused the data transfers. If you look for something that happened at midnight it won't be there. You need to look over the course of a day. You can get an app like dataman that will tell you when each transfer occured, and optionally where you were when it occurred.

The data transfers really happened. You need to figure out which app or apps are responsible for them. Start with those that use Notifications. And if you have Facebook or other social networking apps it is probably one of them. Unless you use the Maps app, which uses a huge amount of data.

Mysterious nightly data usage issue—partial explanation.

Background:

I recently signed up with AT&T for the 200 MB plan and got my 1^st smart phone: iPhone 4s. Then, noticed that my average daily data usage was exceeding 6+MB (in order to stay within the 200MB limit). I was mostly using internet at home using WiFi. But, at work, I had to rely on AT&T network for emails and occasional web browsing. On some days, the usage was 17MB which I couldn’t comprehend. And, the time stamps were like 12:38 a.m. when I was sleeping with the phone in stand by/sleep mode.

I called AT&T twice, read the discussion threads of the Apple Support Communities, discussed it with experienced smart phone users, and then did my own research as AT&T reps couldn’t explain what’s going on other than providing me boiler-plate responses.

Explanation:

1. Time to time, the iPhone sends data usage statistics to AT&T; I believe the frequency is at least once a day. The time stamp is the 1^st AT&T network data usage by your phone since the last time iPhone send the stats. The data volume is the total of sent and received starting from the reported time stamp until the next time iPhone sends the stats. The time stamp should have been the reporting time. You may see multiple entries on any given day. Keep in mind that your phone uses AT&T network when you are within a WiFi network, but your phone is in standby mode.
2. Applications like location services, facebook, google maps, etc. continuously exchange data with your iPhone. When you open facebook, you see the most current state and instantly get all the updates which is cool. But, this requires your facebook to constantly communicate with your iPhone using the AT&T network when your phone is not in a WiFi network or it is in standby. Plus, these websites have lots of graphics--they quickly add up.
3. The junk and marketing emails that you delete without even looking all add up to MBs every day. These come with lots of graphics.

Remedy:

1. If you don’t like to headache, pay $10/month extra to move to the 2GB/month plan. I am not ready to do it now.
2. Turn the General>Network>Cellular Data option ON only when you need it.
3. Log out of any web site after your visit so that the data exchange mentioned above stops for applications like facebook.
4. Kill applications that run in the background even when you quit, e.g. Maps—double tap on the home button, put your finger softly on any application and hold until they show the red-circle with a negative sign—click on the “-“ sign one by one so that they are not running on the back ground.

In order to experiment yourself, play with the General>Usage>Cellular Usage>Reset Statistics along with turning the General>Network>Cellular Data option ON and OFF to monitor your usage and get a feel for how you are doing. Based on the limited information available to me and those provided by the AT&T reps, I’m confident that the data usage information is accurate.

I hope this helps.

See within the quote below for my comments to this, marked with -->

winmass66 wrote:

Mysterious nightly data usage issue—partial explanation.

...

Explanation:

1. Time to time, the iPhone sends data usage statistics to AT&T; I believe the frequency is at least once a day. The time stamp is the 1^st AT&T network data usage by your phone since the last time iPhone send the stats. The data volume is the total of sent and received starting from the reported time stamp until the next time iPhone sends the stats. The time stamp should have been the reporting time. You may see multiple entries on any given day. Keep in mind that your phone uses AT&T network when you are within a WiFi network, but your phone is in standby mode.
   --> This is almost right, except that data usage is reported by the carrier's own equipment, not by the phone. In other words, AT&T does not rely on your iPhone to report how much data it sent and received. AT&T already knows this. The usage information is reported by the various "switches" (or whatever the right term is) that serviced your phone within the network.
   
   
2. Applications like location services, facebook, google maps, etc. continuously exchange data with your iPhone. When you open facebook, you see the most current state and instantly get all the updates which is cool. But, this requires your facebook to constantly communicate with your iPhone using the AT&T network when your phone is not in a WiFi network or it is in standby. Plus, these websites have lots of graphics--they quickly add up.
   --> That has not been my experience with the Facebook and Maps apps. Facebook usually updates to the latest information slightly after I open it, whether or not I killed the app after last using it. A well-designed app should not use large amounts of data in the background unless there is a clear reason for it, like continuing to download a song or something. There are apps that do use some background data to keep a connection, like Skype, mMil, all the iCloud stuff (including things like Find My iPhone/Find My Friends), etc., but my experience is that most of these (especially the built-in ones) use only trivial amounts of background data to do their thing.
   
   --> That said, I have occasionaly seen situations where this breaks down: At one time the CNN iPad app was bad about continuous background updating, and I had to remind my wife not to just put the device to sleep with the app in the foreground. For good measure we even took to killing it instead of just pressing the home button. I don't know if they have fixed this as I've not tested it lately. I also had a situation once with the Facebook app where I started to watch a video and then changed my mind after I realized it was huge. (I don't remember if it was a Facebook video or a YouTube video linked through Facebook or something else. I think it may have been a video on a Safari web page displayed within the Facebook app.) Even though I pressed the home button to leave the app, by looking at the usage stats on my phone (both the built-in one and DataMan), I could see that it was still downloading the video. In that case I had to force kill the Facebook app. But again normally this doesn't seem to be required. (I've also read in this thread where some people thought their mail client got stuck in some sort of loop. That would definitely use a lot of data and the best solution for that would be to reboot the phone and/or reconfigure the mail account, since I'm not sure killing the mail client from the task manager actually kills its associated background processes.)
   
   --> I've also developped a habit of always pressing the Home button before putting the phone to sleep. At one time I thought this would tell iOS that I wanted everything to behave as if it were in the background (meaning no processing and no downloading unless necessary). However, I don't know if this is or ever was necessary, because you'd think when you put the device to sleep iOS would put everything in the background anyway. But this is just something I do now out of habit and an abundance of caution. But that's usually where I leave it. Unless I have reason to be suspicious of a particular app, like CNN, or an aborted download, or sometimes something like Skype, I don't usually kill background apps. I think it's overkill. I rely on the OS to manage memory, background downloading, etc., and it usually works fine for me.
   
   
3. The junk and marketing emails that you delete without even looking all add up to MBs every day. These come with lots of graphics.
   --> Maybe, but my iPhone (only using IMAP accounts) downloads only headers and part of the message at first. If I delete the message without opening it, not much would be downloaded. Even if I open it, if it's a very large message the iPhone only downloads some of the message at first when you're on a 3G connection. You have to tap a button at the bottom of the message to get the rest. Compared with things discussed above (like apps stuck in a loop, or downloading large videos you didn't mean to download), I don't think junk mail add up to all that much.
   
   

Remedy:

1. If you don’t like to headache, pay $10/month extra to move to the 2GB/month plan. I am not ready to do it now.
   --> I'll admit I couldn't easily live within 200MB anymore, though I used to. See below.
   
   
2. Turn the General>Network>Cellular Data option ON only when you need it.
   --> I think this is overkill unless you are one of the relative few who has some rogue app they have not been able to track down.
   
   
3. Log out of any web site after your visit so that the data exchange mentioned above stops for applications like facebook.
   --> I usually leave lots of pages open in mobile Safari with no noticeable data consumption resulting therefrom. However, certain pages with scripted refreshes or something could in theory be a problem, so this is probably good advice. (Though again, I'm not sure how much Safari is supposed to be doing much when it's in the background.)
   
   
4. Kill applications that run in the background even when you quit, e.g. Maps—double tap on the home button, put your finger softly on any application and hold until they show the red-circle with a negative sign—click on the “-“ sign one by one so that they are not running on the back ground.
   --> Again, I think this is overkill for most folks, except if there is a particular app that you suspect of being troublesome. Maps uses lots of data when in use, sure, but I've never in three years noticed it using any background data. Apple did not design the device to require you to regularly kill all the background apps. The OS generally does a good job of giving things processor time and memory only when they need them, etc. It's not perfect (especially with memory management), but problems with unexpected downloads seem to be the exception for me, not the rule, and I've a heavy and experienced user.
   
   

In order to experiment yourself, play with the General>Usage>Cellular Usage>Reset Statistics along with turning the General>Network>Cellular Data option ON and OFF to monitor your usage and get a feel for how you are doing.
--> This I agree with. Use this and/or Dataman to get a feel for what uses data. Be aware that using DataMan in the Precise Tracking mode will use a lot of battery power, especially if you are connected to WiFi, as it seems to keep the WiFi connection alive instead of allowing the lower-power 3G to take over. Instead I leave Precise Tracking turned off and just launch it a few times a day to update it. I launch it especially after doing something I suspect was data intensive to see what the result was. If you're using it this way note that it's a good idea to launch it right before bed and first thing in the morning so the daily totals are right. You must also launch DataMan right before you power down the phone to capture the latest usage. Also, whether using Precise Tracking or not, you must launch the app again upon rebooting so that it starts tracking usage again.

Based on the limited information available to me and those provided by the AT&T reps, I’m confident that the data usage information is accurate.

I hope this helps.

Now, to be fair, I don't think I could live within a 200MB plan anymore. (I could a couple of years ago.) I've become a pretty heavy user, especially now that I (a) work somewhere with no WiFi, and (b) use iCloud for calendaring (which uses a noticeable amount of data to push events to my iPhone on days when I'm doing a lot of editing of appointments in Outlook or in iCloud online). In a typical month I now use something between 300MB-600MB (on a 1GB plan). I monitor usage fairly closely and have a good idea by now where the data goes, and I don't think following the advice above would get that number significantly lower.

Message was edited by: chcn (formatting and added some more comments on how to use DataMan)

I can see what you're saying about the data transfers being listed together and the Wi-Fi issue overnight. However, these don't answer my problems. I have an iPhone 4S, and this is the first week I have seen large quantities of data transferring after I am asleep.

1. I keep my iPhone plugged in all night (and it's still plugged in during the morning), so any activity should still be going through the Wi-Fi network.
2. I work in a job where we cannot have cell phones out during the day (so no heavy usage is occurring then).
3. My iPhone connects to my Wi-Fi (provided by AT&T, like my mobile phone service) as soon as I get home from work.
4. I use Siri only occasionally, and I have only used navigation services of a maps app on a couple of weekend vacations.
5. I have iCloud back up turned off, so nothing should be happening there either.
6. My main usage is email, Facebook, and Words with Friends over a Wi-Fi network. I don't look at attachments or pictures very often without Wi-Fi, and I don't use my phone to stream movies or music.
7. My provider itemizes data usage to the minute on my bill. Looking back over the past couple of months' bills, I don't have 7-16MB data transfers at 10 or 11PM very often. This week, it has happened on Monday, Tuesday, Wednesday, Thursday, and Friday when I have already gone to sleep.

If there has been any change to my usage this past week, it's been in using my phone's data plan less than usual. Because of work being very busy this week, I have been using my phone basically in the evening at home where my wi-fi access is, and yet this week seems to be my highest usage week I've had on my plan so far. What all this tells me is that something changed in the past week or so with my service--whether it is AT&T having glitchy Internet service at home or something else.

I have another data app other that Dataman, but it doesn't itemize individual data usage points. I downloaded Dataman Pro this morning to see if I can target when this is happening. However, I am pretty baffled by what has been happening with my phone this week.

Matt Wolanski wrote:

Also I don't believe wifi goes off went the screen is off since wifi sync to iTunes works when the screen is off.

You can believe what you want, but WiFi goes off about a minute after the phone goes to sleep, unless it is connected to power. To prove it to yourself do this test:

1. Go to Settings/WiFi and tap on the arrow to the right of the network name and write down the IP address of the phone.
2. Open a Command window (Windows) or a Terminal window (Mac) on your computer
3. Type "ping xxx.xxx.xxx.xxx", substituting the IP address for the x's. (use "ping -t xxx.xxx.xxx.xxx" on Windows)
4. You will get a series of resposes showing ping times.
5. Put the phone to sleep.

After about a minute you will stop seeing responses and instead get a timeout message.

I just did some quick discovery of my own situation; here is what I find:

• My wife's highest total usage in any previous month (April 2011-January 2012) is 81MB.
• My wife is using my old Apple 3G.
• This month, my wife is at 160MB with 10 days left to go in the billing cycle.
• My wife and I both downloaded Words with Friends just before the beginning of this billing cycle and have been playing it regularly.

Opinions?

GleeSC wrote:

I am seeing the same thing. We have (4) iPhones on a single account, and at least 2 of them are sending copious amounts of data when their users are sleeping and WiFi connections are available. This is a bug. Either AT&T is billing us for diagnostic packets, or something is not properly using the WiFi network.

You didn't read much of the thread.

1. The data does not transfer when users are sleeping, it is recorded in the billing system at that time and is accumulated data usage over an extended period during the day.
2. WiFi connections are NOT available when the phone is asleep. WiFi is turned off when the phone is not actively being used to conserve battery. So any data transfers when the phone is asleep and not plugged in to power will go over the cellular network.

All of this has been repeated hundreds of times in the thread and confirmed. The ONLY way to find out when the data transfers actually happen is by purchasing a monitoring app such as Dataman or Onavo.

To repeat what has been said at least a hundred times in this thread already:

• The time of a data transfer on your bill is NOT the time the transfer actually occurred. It is accumulated time of individual transfers over the previous day that is reported to the billing system as a single summary line.
• WiFi is turned off to save battery when the phone goes to sleep if the phone is not plugged in. So any apps that use data in the background (and there are a lot of them) will use 3G rather than WiFi even if you are in range of a WiFi network. This includes streaming apps. To keep WiFi on you must have the phone connected to power.

Lawrence: Thanks for the additional information. Unfortunately, AT&T's billing practice is still unclear:

Large and detailed AT&T bills: Paper bills would be impractical for detailed reporting of data transactions. AT&T's online client service portal, however, could easily provide a complete recap of data charges -- plus the ability to download a CSV version. This functionality is currently in place for SMS messages and calls, but not for data transactions. In addition, AT&T's own customer service managers and technical support team cannot access and explain our data bills. This is puzzling and frustrating for customers, damaging the reputation of AT&T, the iPhone and Apple.

• Multiple 'aggregate' billing events due to travel and multiple MTSOs: This additional info is helpful, but does not explain our bills. The strange charges listed in my previous post occured when our son's iPhone 4s was in our house, He was not traveling with it from area to area -- and tower to tower.
• Tracking data usage with Dataman and Onavo: We downloaded both, to try to reconcile and audit our AT&T bills. I will report the results as soon as the next billing cycle closes. This highlights the problem, however. Customers should not be forced to buy apps, monitor data usage and try to audit their bills every month. It is AT&T's responsibility to provide sufficient detail to explain their bill -- just as they do today for calls and SMS messages. On the technical side, there is no way to accurately audit AT&T's bill with Dataman or Onavo -- due to the 1 to 5 day delay in posting aggregate transactions, and the lack of date / time detail.

Let me post an experiment that I have started in case others would like to try it. Frustrated by the same problem others have been describing here and with no ability to look at the cellular packets, I created a setup where at least I could monitor all of my iPhone’s usage while on a wireless network. Skip down below to see the setup and results so far.

First, my problem: 2 iPhones demonstrating similar behavior as those in this forum but I will focus just on one. This iPhone has an unlimited domestic data plan grandfathered in with AT&T and a 125MB international data plan. The last two times we were in the Caribbean, we got overage notices and then got shut down by AT&T (which was probably good since the bill had gone over $1000 each time).

In looking at the billing statement, we had single 350MB line items on the bill almost every day. I will spare you all of the details of the conversations that I have had with AT&T since they have gotten nowhere. I do understand that the 350MB line item was an accumulation of all of the usage for the day and that even though it said “sent”, it was a combination of both.

For the record, I do have an MCell but that should be out of the equation when we are in the Caribbean.

Second, my experiment: Though I understand that some applications on the iPhone will send more data when connected over wireless than when connected over cellular, I believe that if you watch the iPhone’s packets while connected over wireless, it will pretty much contain at least all of the data packets that would be sent over cellular. So I did the following for my setup:

1. ) Set up my Mac for internet sharing. Doing this, I had wired Ethernet coming into my Mac and it provided a wireless network different from that in my home.
2. ) I set the iPhone to use this new wireless network and had it as the only device on it.
3. ) I ran Wireshark, a free packet analyzer, on my Mac on had it capture all packets that went over this new wireless network.

Third, my early results: Wow, there was a lot of activity! In capturing data for 18 hours, there were 461K packets. Scanning them quickly, here are the most common IP addresses and who owns them:

The biggest offender seems to be 173.194 group belonging to Google, particularly 173.194.68.109 and it seems to be primarily outgoing. A large number were 1484 bytes in length.

Though I don’t understand why either Amazon or Microsoft are in the mix, I concentrated on Google. The phone used IMAP for gmail so I began investigating that. To see if there was a difference, I switched it to use Exchange as described on Google’s setup page and it did not seem to make a difference in the traffic.

One of the first interesting things I noticed is that if I am reading email on my Mac, when I select it and it goes unbold to designate read, the unread count on my phone is updated in less than a second (impressive). However, in order to pull this off, 27 packets are sent between my iPhone and Google, including two from my iPhone that are 1484 bytes each. If I delete a message on my Mac, it is about 50% worse.

If on my iPhone, I look in a mail folder that has only three mail messages, 50K of data is sent to my phone.

More experiments will eventually follow when I have time.

Feel free to comment on the validity of this experiment or post your results from a similar experiment.