NFC - why do you need a special sim with support for this technology?

Question

Computer networks

Mobile ticket, you need a phone with an NFC adapter-special SIM card (NFC tag) - a reader (turnstile).
There is clearly something missing here.
And are there adapters for android NFC?

Answer 1

A SIM card with "NFC support" is no different from a regular one, it's just that a certain operator has an agreement with a certain bank to conduct transactions on payment for transport services, therefore you need a SIM card from this operator with a certain tariff plan.