Is the signals of a mobile phone-call encrypted between the phone and the mobile-tower or only between the towers? And is it possible for a non-authority individual to eavesdrop on your conversation if he picks up the signal between the phone and the tower?

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    You might find security.stackexchange.com/questions/35376/… interesting reading - in short, GSM encrypted everything from phone to phone, but not very well. It would be unusual for a later standard to drop the encryption requirement, so 3G and 4G probably do the same. – Matthew Sep 18 '18 at 13:46
  • Not sure it's entirely a duplicate, since it's not specific to GSM, although it's clearly closely related. – Matthew Sep 19 '18 at 7:33
  • Hi @newbie and welcome to Security SE. As posted, your question is too general without specifying more details. It will surely be either down-voted or flagged as such. Please provide more details and clearly post one question. – not2qubit Sep 19 '18 at 9:08

All normal (GSM,CDMA,UMTS,LTE) mobile network communications are encrypted, except when it is not. For example, very old 2G GSM networks may only offer A5/0 or A5/1 "encryption", which is in effect none or broken.

Many other protocols are also already broken. See: Cellular encryption algorithms currently in use globally.

Some attacks are done by downgrading the communication from a safe/encrypted protocol to a broken one.

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  • Do you know how I might know what technology my phone is using? When I google it's specs I find a site that lists everything from GSM up to 4G so how do I know what it's actually using when I call? – Elec0 Sep 24 '18 at 7:53
  • And how could someone downgrade your phones protocol before attacking it, shouldn't he need to already be in control of the phone to do that? – Elec0 Sep 24 '18 at 7:57
  • You simply jam the other frequencies used by UMTS, LTE etc. Unless the phone has been set to exclusively use LTE (for example), it would go back to UMTS or GSM, if LTE connections were blocked. – not2qubit Sep 24 '18 at 10:48

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