OsmoDevCon 2024: "Detailed workings of OTA for SIM/USIM/eUICC"

I've presented a talk Detailed workings of OTA for SIM/USIM/eUICC as part of the OsmoDevCon 2024 conference on Open Source Mobile Communications.

Everyone knows that OTA (over the air) access to SIM cards exists for decades, and that somehow authenticated APDUs can be sent via SMS.

But let's look at the OTA architecture in more detail:

  • OTA transport (SCP80) over SMS, USSD, CellBroadcast, CAT-TP, BIP

  • The new SCP81 transport (HTTPS via TLS-PSK)

  • how to address individal applications on the card via their TAR

  • common applications like RFM and RAM

  • custom applications on the card

  • OTA in the world of eUICCs

  • talking to the ECASD

  • talking to the ISD-R

  • talking to the ISD-P/MNO-SD or applications therein

You can find the video recording at https://media.ccc.de/v/osmodevcon2024-175-detailed-workings-of-ota-for-sim-usim-euicc