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Q1. Please elaborate your understanding about how RFID and NFC work. What are the current security considerations and challenges?
As the era of ecommerce expanded, the need to identify products without a physical contact and without error increased. This made companies to work upon new methods of reading product information apart from barcode. Barcode needed a physical scanner in near vicinity of the code label. With huge inventories and multiple ways the products could be aligned in a place, led to limitation of the use of barcode for identification.
The solution came up in form of radio based tags that could be attached to products and read from a distance using radio scanners. Several of the problems that existed with Barcodes was no more a limitation in case of radio tags.
There are two main standards used at the commercial level. One if RFID i.e. Radio Frequency Identification. IT uses a RFID smart tag continuing a microchip holding the information and an antenna capable of communicating with the RFID reader. The RFID reader sends out electromagnetic waves in the UHF or low –frequency range to scan the tags. The range of reading the tag depends upon power being used to scan. UHF based readers can read faster and can scan from distance greater than what is possible with low-frequency scanners. LF scanners have advantage of consuming low power but also reduced scanning range. The technology can be selected as per use case of the application.
Another technology in use is NFC i.e. Near Field Communication. This is also a radio based technology that scans a microchip to read data. This is widely in use with mobile phones, embedded into phones for identifying the user. The range of NFC is too small compared to RFID limited to only a few centimetres. It uses a 13.56MHz frequency for setting up communication channel.
Both RFID and NFC technology only define the radio standard for communication. Neither one of these defines what data gets exchanged...