Inspecting the network packets for their TTL (time to live)Įvery network packet travelling across a TCP/IP network, like the internet, has a built-in time-to-live ( TTL) set on it, so that in case there is a problem with that packet reaching its destination this will stop it travelling around the network forever clogging everything up.
However I haven't found any concrete evidence of this, other than people finding odd APNs and wondering what they're for (bear in mind that an unlocked phone bought off-contract may have hundreds or thousands of APNs stored on it, ready for use on whichever network in whichever country the eventual owner decides to use it).
It's also rumoured that some phones have a second set of APN details saved in them by the phone network, when you enable tethering they switch over to using this second APN for all tethered traffic, while using the normal APN for traffic originating on the phone. Your phone tells your network that you are tethering This generally only happens if you are running an OS version that has been customized by your Provider, example 1 example 2.
#Phones pda net works with hotspot software#
The first and easiest method is that some phones will query the network to check whether the current contract allows tethering, and then totally disable the tethering options on the device in software if not. However there are certain known techniques that will give away the fact that you're currently tethering, if your Service Provider happens to be running the right tool to check for these indicators: Your Phone asks your network if tethering is allowed How they detect that someone is tethering a device isn't something that network providers often want to talk about, for the obvious reason that the more consumers know about how this is being detected, the easier it is for them to find ways to hide the fact that they're doing it, and avoid the associated extra charges (1).