Is there a difference between NFC and RFID?
It’s a bit about definitions and how they are used. NFC is actually an RFID technology. However, mainstream RFID technology is now used for longer distance identification technologies. HF RFID systems can identify up to 50 centimeters, UHF can identify up to 10 meters to 100 meters depending on the type, while systems defined as NFC usually cannot exceed 1-2 centimeters.
When it comes to the volume of data that can be read, RFID technology can make a serious difference to NFC. While hundreds of tags can be read at the same time with RFID, NFC aims to read one tag at a time and this is aimed to be over a short distance. Imagine what would happen if the credit cards in your pocket could be read from 5-6 meters?
RFID is a technology mostly used for “identification”. Asset identification, inventory counting, etc. NFC is more suitable for projects such as contactless payment systems, managing after-sales product experiences, data sharing.
Maybe it’s a technical detail, but I think the most impressive difference between the two technologies is that RFID has a unidirectional communication capability, while NFC has a bidirectional communication capability according to the architecture. So what does this mean? RFID tags are just tags and they are loaded with RF signals emitted by RFID readers and they broadcast the ID of the chip on them unidirectionally with this energy. Yes, NFC also has this type of usage. For example, scanning your business card with a cell phone. But there is a second way NFC works. This is called bidirectional communication and it allows two NFC devices to interact with each other in both directions. For example, two cell phones with NFC can transfer files between themselves.
The final word is that the RFID world shares many arguments about security, but NFC has always struck me as a more secure technology. This is why no credit card has ever been produced with Class 1 Gen2 (and v2), the most widely used protocol of RFID in the world today.
Is there a difference between an NFC tag and a card?
The direct answer is no. The chip used in both is the NFC chip. The reason why some call it a card and some call it a tag has more to do with the form factor and intended use of the “thing” in question. It is true that NFC tags are attached to every product sold, but NFC cards equipped with the same NFC chip can also be used by employees in a company to use personnel access systems.
I want to develop projects with NFC but I don’t know which one to choose, what should I do?
Please don’t spend too much time on this when there is someone here who has studied these topics. Let’s start with the quickest answer. Most NFC projects are being developed around interaction with cell phones. If you are going to have an application related to smartphones in your project, my recommendation is to use an NFC tag with an NTAG chip. Because today’s NTAG series NFC systems are compatible with almost all smartphones.
Of course, if we need to go into detail, we need to talk about NFC chip types first. We can count 5 types. Let’s go through very roughly:
NFC Type 1 (ISO 14443-A) has a memory of 96 bytes. It communicates at 106 kbps. No data collision algorithms. It has read/write or read only modes. It has a low price. Not very common anymore.
NFC Type 2 (ISO 14443-A) has 48 or 144 bytes of memory. Communicates at 106 kbps. Has data collision algorithms. Read/write or read only modes. The most known productions are NXP Mifare Ultralight. It has a
low price.
NFC Type 3 (ISO 18092) has 1, 4 and 9 kilobytes of memory. Communicates at 212 or 424 kbps. It has data collision algorithms. Read/write or read only modes. The best known productions are Sony Felica. It is actually higher performance in terms of speed and capacity than Type 1 and 2, but it is not very common. For example, in all these years I have never been able to work with these chips. The most expensive chip is produced in this type.
NFC Type 4 (ISO 14443-A) has 4 or 32 kilobytes of memory. It communicates at 106, 212 and 424 kbps.
It has data collision algorithms. Its notable feature is its security capabilities. Read/write or read only modes. The most known productions are NXP DesFire. The second most expensive chip is produced in this type.
NFC Type 5 (ISO 14443-A) has 192, 768 or 3584 bytes of memory. It communicates at 106 kbps. It has data collision algorithms. Read/write or read only modes. The most known productions are NXP MiFare Classic. They are low priced.
I think that’s enough for now, let’s meet in the second part soon. We will continue with NTAG2xx, Mifare, SLIX, EM4425x, ST25x chips. Don’t worry, I will be sharing everything you need to determine the most suitable NFC technology for your project.
In the meantime, click here to review NFC tags
