NFC card emulation

Question

I would like to write an application where I can store NFC tag on my phone so that NFC readers can access it. For example storing a boarding card on phone so that it can be accessed by NFC reader at the airport. I guess it can be implemented beaming NDEF messages, however in order to do that the phone needs to be on. My problem is, I need to get it working when phone is off. As per my understanding, the only way is to store the NFC TAG in Secure Element (SE) so that it can be emulated as card. NFC reader's power can be used to access information stored in SE.

Is there anyway I can store my TAG to Secure Element? As per my search so far, there is no way to access SE directly. Following post talks about it, not sure if things are changed since the time it was posted. NFC card emulation Android

If storing in SE is not possible, is there any other way to store TAGs on the device so that it can be read by NFC reader when phone is off.

Thanks B

Answer 1

When it is a strict requirement that your emulated card ("NFC tag" is not necessarily the best terminology to use in that context) is accessible while the phone is powered off, then your only option is to use a technology that bypasses the phone's main application processor. Consequently, your only option is to use a secure element.

Accessing the SE: This requires cooperation with either the device manufacturer (for embedded SEs) or the mobile network operator (UICC/SIM card). If you have that cooperation, they will likely be able to give you further advice on how to access their SE. If you don't have that cooperation, then there is pretty much no way to get access to an SE on a production device. (I did not mention the µSD scenario, as this is completely idependent of a device's NFC chipset.)

Other options: All other communication through the NFC interface is performed by the mobile phone's main application processor. Thus, in order to have such capabilities (peer-to-peer data exchange, host card emulation, inverse reader mode) the device needs to be powered on and have its operating system loaded.