Difference between NFC-A and NFC Forum Tag Type 1

Question

NFC Forum has created a own protocol which is a standard that combines NFCIP-1 , ISO/IEC 14443 (RFID) and FeliCa specifications together. That protocol standardize eg the 4 tag types and the NFC modes (reader/writer, peer-to-peer, card-emulation) and is also called the NFC Digital protocol .

According to NFC Forum:

• NFC-A corresponds to the ISO/IEC 14443 Type A standard
• Type 1 tag is based on the ISO/IEC 14443 Type A standard

For what technical or functional reason is NFC-A difference of ISO/IEC 14443-A ?

What is the difference between a NFC-A tag and a Type 1 tag? Are they two different things or is the Type 1 tag just an implementation of NFC-A , which only means an implementation of ISO/IEC 14443-A ?

Android implements NFC-A , but the ACR122U implements ISO/IEC 14443-A ? What's the difference?

Answer 1

For what technical or functional reason is NFC-A difference of ISO/IEC 14443-A?

The idea behind packing those NFC-related standards into the Digital Protocol specification seems to be certfiability and validatability. Basically, the NFC Forum can only certify technology based on their own standards (eg they have no authority to certify that devices comply to ISO standards). Moreover, as you already note in your question, the NFC Forum specifications (not only Digital Protocol, but also Analog, etc.) combine multiple independent standards (ISO 14443, ISO 18092, etc.) into one consistent protocol specification.

What is the difference between a NFC-A tag and a Type 1 tag?

NFC Forum Tag Operation specifications define memory structures, memory manipulation/access commands and access strategies for NFC tags. They are defined on top of the protocols specified in the Digital Protocol specification. For instance, the Type 1 Tag Operation specification defines an NFC tag platform that operates on top of the NFC-A protocol.

Android implements NFC-A, but the ACR122U implements ISO/IEC 14443-A? What's the difference?

For detailed differences I suggest that you compare the requirements of both. In general they can be considered to be equvalent -- though there seem to be some areas where one of the two specifications is more restrictive than the other.