How do mobile phone companies detect if you are sharing your 3G/4G internet connection? -


i spoke phone company in denmark, offer "free 3g/4g", on phone, have limitation if create hotspot , share connection, limitation on 50gb.

how detect if mobile device sharing connection? intercept special headers computer/other phones send on connection?

mac addresses used @ lower layer ip , relate each hop or leg of end end communication don't issue.

detecting tethered devices quite complicated task , there special solutions this. tend @ multiple things try determine if other devices using mobiles connection, if devices spoofing or manipulating headers etc.

examples of things solution at:

  • number of simultaneous sessions
  • http user-agent headers
  • device type
  • device screen size
  • tcp timestamp
  • tcp source port
  • tcp sequence number
  • application-based correlation tcp flows
  • node-pair correlation tcp flows

see here example solution , more details of above (this 1 example solution):


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