By public transport, I assume you mean fare collection, as opposed to asset tracking and other applications. The most popular choice for transit is passive high-frequency (HF) tags based on the ISO 14443 air-interface protocol standard, which was designed for secure transactions.
Some transit operators have begun testing phones containing an RFID system known as Near-Field Communications (NFC), which enables people to use their cell phones both to read RFID tags and to transmit data as if it were a tag. San Francisco’s Bay Area Rapid Transit and other systems have tested NFC-enabled phones (see SF’s Transit System Offers Commuters Fast Access to Subways and Sandwiches), but there aren’t yet many phones with NFC capabilities.
Some bus companies have also rolled out RFID for tracking cash boxes (see Bus Co. Keeps Tabs on Fare Boxes).
—Mark Roberti, Editor, RFID Journal
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