Network counter and tethering

Avast Mobile Security Avast Mobile Security for Android
1

In tethering mode (3G link to internet and Wifi link to a local laptop)
the wifi trafic is added to the 3G one giving a 3G network trafic counter about double that actually.

Could someone confirm ?

Regards.

2

Hi, I haven’t tested it, but my guess would be that the wifi traffic (i.e. laptop ↔ phone) is added to the wifi counter, the 3G traffic (i.e. phone ↔ internet) is added to the 3G counter, and the laptop ↔ internet (with the phone as an intermediary) is added to the 3G counter. So, the traffic from your laptop to the internet is counted twice, first to wifi, then to 3G. Seems completely logical to me :slight_smile:

Ondra

3

Thank you for answering.

I think your hypothesis is right. The Wifi trafic and the 3G trafic are both cumulated in the 3G network counter.

But I disagree with your conclusion. It is NOT logical. 3G must go to 3G, and Wifi must go to Wifi.

With Wifi trafic mixed with 3G, it isn’t possible to use the 3G counter to check the internet trafic invoiced by your ISP.

Regards.

4

I don’t think we understand each other. The wifi and 3G traffic is not cumulated in 3G, only the traffic from your laptop is counted twice - once in wifi and once in 3G. If you use your phone normally (without tethering), then everything should be in order. But, if you are wifi-tethering the internet connectivity to your laptop, then your laptop in fact uses your phone’s 3G connectivity.

Ondra

5

I understand what you mean now.
We both agree upon the fact that, without tethering, the 3G counter (and the other ones) is correct.

According to you, in tethering, the laptop has a 3G trafic (across the smatphone) and the smartphone has a 3G trafic.
That is logical from your point of view.
But both 3G trafics are composed of the same bytes, and physically, travel just once between the smartphone and the ISP.
It’s confirmed by the ISP accounting (half of the avast! 3G counter).
Thus it’s illogical from my point of view.

Regards.

6

Could you try to spot which app’s counter is being added to when you download something using your laptop? Maybe the traffic is counted to some ‘tethering’ app and also to some of the system groups.

Thanks,
Ondra

7

Can you please provide us an info about your device (OS, type, kernel version)? I have tried it on SGN with 4.2.2 and the traffic is displayed only in 3G counter and correctly.

8

Thanks for your attention.

I did a tethering session as pure as possible…

avast! Network Meter 3G
All Applications 6.51 MB
Other applications (mostly synchronisation and overhead) 0.07 MB
(Facebook, Weather app, Dolphin browser and associated modules, Mail app)

Android system settings / Data usage Mobile
Total 3.26 MB
Tethering & portable hotspot 3.09 MB
Android OS 217 KB
Facebook 41.06 KB
Mail app 28.37 KB
Weather app 24.39 KB
etc… smaller quantities.

Device Samsung Galaxy GT-i9000
Android version 4.2.2 CyanogenMod 10.1-20130221
Kernel 3.0.63-Semaphore_JB_2.9.10
Note: Android versions 4.1.2 and 4.2.1 (with respective kernel and CyanogenMod) installed in the past,
have given the same result regarding avast! Network Meter.

Regards.

9

So the problem here is that Tethering group shows 3.09MB and total shows 6.51MB, right? Unfortunately we depend on what the system tells us. We don’t just show the sum of all apps in the Total, but we instead show what the system tells us is “total”. This might include some traffic that isn’t counted in any of the apps below, but is still transferred (I know you said that your carrier says it’s more like the Tethering app alone). Strange thing is, that sometimes the system reports even lower values than the sum of the apps. Apparently Android isn’t perfect :slight_smile: But we’ll sure look into it.

Jan was able to reproduce some of the described behavior, but it happened pretty randomly. I don’t even have the Tethering & portable hotspot app in the list, so it might also be a CM issue. We’ll have to investigate it a bit more, but thanks for the report.

Ondra

10

You said “So the problem here is that Tethering group shows 3.09MB and total shows 6.51MB, right?”.

In that sentence, 3.09MB is the quantity reported by Android as belonged to the Thetering group.
6.51MB is the total quantity reported by avast!.
Maybe there is some confusion there.

To explain the figure is other words:

  1. Android says: total 3G traffic is 3.26MB.
    Included is this figure, the Tethering group is responsible for 3.09MB
    and the other functions/apps are responsible for 3.26MB - 3.09MB = 0.17MB
    Note: the sum of Android OS, Facebook, etc… is more than 0.17. There are some approximation or overlap there…

  2. avast! says: total 3G traffic is 6.51MB.
    No individual report of Tethering group traffic.

  3. My ISP accounting is far nearer to the Android total figure.

For me the figure that avast! displays as total, is more like the total of Android total + all the traffic related to “system functions” (which
include tethering). Some values could be added twice (by Android or avast! ? I don’t know).

Regards.

11

Ah, sorry, my mistake, I was too quick reading it.

From this it looks like that the OS is actually giving us wrong numbers (which are somehow very weirdly close to a double of actual traffic). I’ll file a bug and we’ll see what we can do.

Thanks!

Ondra