Phone used data while connected to wifi and tethered

[zineer]

Hi all,

My mom has an iPhone 6 on my account through the family share plan. Last night we were at their house for dinner and one of my niece's was on youtube while the phone was connected to the laptop charging. Shortly after we got a message that we had used $50 in data overages and our data was being blocked! I looked at our account online and we had used 3+GB within the time she was on youtube. I looked at the phone and indeed it did show 1 connected device on personal hotspot (the blue bar at top). However, the phone also showed it was connected to wifi with full signal.
I tried to access the internet on the laptop with the phone connected and was redirected to a "blocked due to data overage" page. I disconnected the phone and both the laptop and phone were able to access the internet fine since they were connected to wifi.

I web-chatted with support from my cell provider and they credited my account the $50 in overages, but I'm still at my data cap for the next 23 days until my billing period is up, so any additional data I use I will be charged for. She suggested that the phone will use cell data instead of wifi if the phone doesn't have a good wifi signal, but the phone showed full wifi strength when I looked at it and it was able to connect to the wifi fine directly on the phone. We were only ~15ft from the router with a clear line of sight.

Anyone have any issues with this or any insight onto why the phone would route over the cell network versus wifi when it has a tethered computer connected?

Thanks!

 

[chabig]

In the Network Preference Pane of System Preferences, there is a list of available network connections for the Mac. The active internet connection is green at the top of the list. Normally, Wifi should be above iPhone USB. However, your Mac me be set to prefer the iPhone instead of Wifi. To check, unlock the padlock in the lower left, click on the gear, and choose Set Service Order. Make sure Wi-Fi is higher in the service order than iPhone USB.

 

[scaredpoet]

I tried to access the internet on the laptop with the phone connected and was redirected to a "blocked due to data overage" page. I disconnected the phone and both the laptop and phone were able to access the internet fine since they were connected to wifi.

You need to go into your settings, and under "Personal Hotspot," set this to Off. Your laptop is connecting to your iPhone's Personal hotspot via the USB cable, and using cellular data to access internet. Turning hotspot off will prevent this from happening.

As for your overage, you can turn off cellular data altogether (also in settings) and force your phone to go WiFi only on data, until your billing cycle resets. You'll still be able to make regular voice phone calls, and send and receive texts.

She suggested that the phone will use cell data instead of wifi if the phone doesn't have a good wifi signal, but the phone showed full wifi strength when I looked at it and it was able to connect to the wifi fine directly on the phone. We were only ~15ft from the router with a clear line of sight.

Yeah, if you have hotspot on, all that goes out the window. With hotspot on, your laptop and phone will assume you're traveling or don't want to use existing Wifi for whatever reason, and will default to cellular data when your phone is plugged in to your laptop over USB. Turn Personal Hotspot off, and it won't make this assumption.

This will give you more info:

http://support.apple.com/en-us/HT4517

 

[chabig]

With hotspot on, your laptop and phone will assume you're traveling or don't want to use existing Wifi for whatever reason, and will default to cellular data when your phone is plugged in to your laptop over USB.

That is not correct. When a Mac has multiple network connections, the priority depends upon the service order set in the Network Preference Pane, as I stated above. In this picture, you can see that my iPhone is plugged into USB and a network connection is available, but the Mac is still using wifi for internet...

 

[zineer]

Yeah, if you have hotspot on, all that goes out the window. With hotspot on, your laptop and phone will assume you're traveling or don't want to use existing Wifi for whatever reason, and will default to cellular data when your phone is plugged in to your laptop over USB. Turn Personal Hotspot off, and it won't make this assumption.

This will give you more info:

http://support.apple.com/en-us/HT4517

Thanks for the info! Sure would be nice if the phone didn't show connected to wifi if it was pushing all data over the cellular connection. Most people would assume that since the phone shows it is connected to wifi that is where the data goes, but as the link you posted says "You can share only a cellular data connection; you cannot share a Wi-Fi connection.".
Have disabled personal hotspot going forward. Live and learn!

 

[chabig]

Zineer, it's true that the phone cannot be connected to wifi and serve as a hotspot at the same time. But the computer (I assume Mac) should have been connected to wifi and used it instead of the iPhone USB connection. You should figure out why the computer was using the phone's hotspot instead of connecting to wifi itself. Did the computer not have wifi capability of was it turned off?

 

[zineer]

That is not correct. When a Mac has multiple network connections, the priority depends upon the service order set in the Network Preference Pane, as I stated above. In this picture, you can see that my iPhone is plugged into USB and a network connection is available, but the Mac is still using wifi for internet...

Image

It was a Windows 8 laptop. I'm not sure if my mom maybe accidentally chose to use the iPhone connection over wifi when she first plugged it in or if the laptop automatically assumes since it finds a data capable device connected via USB that it will prefer to use it over its wifi connections. Either way I assumed since the phone was connected to wifi that data would go over the phone's wifi connection, but as scaredpoet posted, the phone only shares its data connection, not wifi, even when connected via USB.

 

[chabig]

It was a Windows 8 laptop. I'm not sure if my mom maybe accidentally chose to use the iPhone connection over wifi when she first plugged it in or if the laptop automatically assumes since it finds a data capable device connected via USB that it will prefer to use it over its wifi connections. Either way I assumed since the phone was connected to wifi that data would go over the phone's wifi connection, but as scaredpoet posted, the phone only shares its data connection, not wifi, even when connected via USB.

I see. I have no idea how Windows decides which network connection to use. This thread will probably be useful to many others. Thanks for posting it.

 

[scaredpoet]

That is not correct.

It most certainly is in this case.