Payment algoritm with NFC

[hadis-soleymani]

I have a big problem. I want to write a program that has my information and can make a payment by holding the phone close to the POS. My problem is that I don't know how the server, application and POS communicate. And how the POS recognizes the customer. And is this possible with your package? I imagine to do this I need to be able to write information to my phone's NFC and the POS can read it.