Not difficult at all. In fact, RFID has been used for digital payments for decades. The first automated electronic toll-collection system was introduced in Bergan, Norway, in 1986. A similar system was introduced in Texas in 1988. These systems employed active RFID transponders.
Passive RFID has been used for digital payments since 1997. That year, Mobil Oil (now Exxon Mobil) introduced SpeedPass at its pumps. A little fob that you put on your car keychain contains a passive high-frequency (HF) transponder, enabling you to pay electronically.
The standard air-interface protocol used for passive HF RFID payment solutions is ISO 14443.
—Mark Roberti, Founder and Editor, RFID Journal
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