Enabling the Ciphering Indicator on Android


  • Felician Alecu Bucharest Academy of Economic Studies
  • Paul Pocatilu Bucharest Academy of Economic Studies


GSM encryption, IMSI catcher, A5, Ciphering Indicator, SIM, AT Commands


This paper exemplifies the use of AT commands to retrieve (and eventually override) the ciphering indicator status on Android by directly communicating with the phone modem. Curiously, his indicator is disabled by default both at operating system level and SIM card settings. By turning it on, the mobile handset will inform the user each time the communication becomes unencrypted, so a proper decision could be made just in time.

Author Biographies

Felician Alecu, Bucharest Academy of Economic Studies

Economic Informatics Department

Paul Pocatilu, Bucharest Academy of Economic Studies

Economic Informatics and Cybernetics Department


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How to Cite

Alecu, F., & Pocatilu, P. (2014). Enabling the Ciphering Indicator on Android. Journal of Mobile, Embedded and Distributed Systems, 6(2), 52-60. Retrieved from http://jmeds.eu/index.php/jmeds/article/view/Enabling_the_Ciphering_Indicator_on_Android