System Services using data even when mobile data is switched off.

[humpbacktwale]

Just noticed this this morning after updated to 14.5.1. Last night, system services had used 131kb. This morning it was 200kb more, all from DNS services. Reset it again and 20 minutes later, it was up to 10kb, all from push notifications. Now the data obviously isn't high, but that is not the issue.

How would system services use mobile data given it has been disabled?

Anyone else had this issue?

 

[BrianBaughn]

Mobile data isn't "disabled" if you're getting push notifications and aren't on WiFi.

 

[humpbacktwale]

I had mobile data switched off and wifi was enabled. I didn't get any notifications, the data usage for push notifications under system services had just went up. It was also disabled when the DNS services usage went up as well.

 

[BrianBaughn]

SMS still works with cellular data off and wifi off. It goes through the cell phone "channel" like it always did before smartphones. Is that what you're seeing? I dunno.

 

[Helmsley]

The Stocks app does this too. Data disabled but still updates.

 

[Shirasaki]

My guess is apple whitelists their system programs to not honour user choices of turning off wifi and mobile data “to maintain basic system function”.

 

[Mr Todhunter]

Just noticed this this morning after updated to 14.5.1. Last night, system services had used 131kb. This morning it was 200kb more, all from DNS services. Reset it again and 20 minutes later, it was up to 10kb, all from push notifications. Now the data obviously isn't high, but that is not the issue.

How would system services use mobile data given it has been disabled?

Anyone else had this issue?

I’m sorry if the question is stupid but how do you reset?

 

[humpbacktwale]

You can reset statistics at the bottom of mobile data.

 

[humpbacktwale]

Tested this again last night. System services had used 720Kb of data. Then the next morning, it had went up by 5 Kb, despite mobile data still being turned off. Is the slider just not working on ios anymore?

 

[humpbacktwale]

Ok so its went up by 16Kb now, and its all push notifications. So it appears disabling mobile data isn't stopping my iphone using mobile data for push notifications.

 

[humpbacktwale]

No increase overnight. Anyone else noticed this?

 

[BrianBaughn]

Ok so its went up by 16Kb now, and its all push notifications. So it appears disabling mobile data isn't stopping my iphone using mobile data for push notifications.

Push notifications for what?

 

[humpbacktwale]

Under system services, in mobile data, the amout of data used went up by 16 kb, and the increase in data came from push notifications. I have no idea why. Mobile data was turned off, and only 2 apps have permissions to use it.

 

[BrianBaughn]

So you didn't actually get any notifications…the data is just shown as used by "push notifications"? Could that be the iPhone pinging the voice data towers to see if there are SMS messages?

 

[humpbacktwale]

No, I received no notifications. I am not confused as to why their would be any push notification data usage if I didn't get any. I and DNS services always use data even if I am not using an app.

What I don't understand is how the usage keeps going up when I have disabled cellular data, and I want to know, if anyone else has observed something like this.

 

[BrianBaughn]

If I turn off cellular and wifi…and use Messages to send (via SMS) a text…the data shows up as used under cellular (and Push Notifications). So, it's reasonable to think that my iPhone pinging the towers in the same state would also, eventually, show some data usage under cellular.

If I'm curioius as to whether or not this data counts against the data limits of my provider I would have to check with them to find out, I suppose.

 

[humpbacktwale]

Yes but wifi hasn't been turned off, it is on, so if SMS was using cellular data, then it should use wifi when that is disabled. More to the point, SMS doesn't use cellular data. I can send and receive texts just fine even if I have no access to mobile data.

 

[humpbacktwale]

Reset my statistics again. When I turned off mobile data, system services was at 60.8 kb, with 55.7 of that push notifications, 2.7 DNS and 2.4 Time. When I checked it again later, it was at 82.5kb, with push notifications having went up by 21.7kb. How is push notifications using mobile data when mobile data has been turned off?

 

[BrianBaughn]

Pinging towers via the voice cellular data connection (the one that ANY "dumb" flip-phone without a data plan uses for voice and SMS) has not been disable on iPhones. It is necessary for regular voice calls to work properly in situations where faster cell data and wifi aren't reachable (which is probably rare these days). I think you can turn it off using Airplane Mode.

The point is…there's TWO cellular data streams going on normally and I suppose iOS lumps them both into the statistics for "Cellular Data" and the switch for cellular data only applies to the fast data stream that apps use. Those apps can't access the voice cellular data stream.

See if your iPhone uses any "Cellular data" when it's in airplane mode and compare that to when you only have wifi and cellular data switched off.

 

[humpbacktwale]

The problem with that theory is that, after I disable it, it seems to go up the first time, and the after that doesn't do so again, at least from what I can tell after beginnin to take not for this post. If that was the case, then it should continue to go up after this first time, but it isn't doing that. For example, I reset it after my comment on Sunday, and there was no further increase.

Rather than determining why this happens, I just want to know if, when other people disable mobile data, and then note what the system service usage is, does it go up again later after they have disabled it?

 

[humpbacktwale]

Reset the statistics a few days ago, haven't used mobile data since. DNS services has used 2.4kb of data. Can't seem to find a pattern here of what is causing this.

 

[JonaM]

I've certainly seen this when I'm travelling and I don't have cellular data so have been surprised to see it going up when roaming and cellular data were switched off.
I concluded it was behind the scenes activity with connecting to cellular networks as it normally seems to appear periodically when moving between mobile networks and was something I never got charged for.

 

[humpbacktwale]

I mean if you reset the statistics, and switched it off, do you notice any small increase? It couldn't even be an issue with my network, as the values under settings> mobile data come from the phone, not the network :/