Hello, We have developed an application for Mifare Classic & Ultralight (Type 1 & 2 NFC), reading & writing UIDs & authenticating it from central application. Though, we haven't worked on DesFire (Type 4 NFC) but worked on JCOP card which is of same family. From your project description, I understand that you want to connect an NFC reader with a Linux box (just like RassberryPi), this linux box integrated with NFC reader will poll data continuously and whenever an NFC Card is tapped on it, its encrypt the data and pass to your application. This is my understanding, please correct it or modify it. I would appreciate if you please share any more info about this project requirement. We can discuss this further after receiving your initial response. Thank you. Regards, Harris.