RFID Standards: 125 Khz (low-frequency) tags are write-once/read-many, and usually only contain a small (permanent) unique identification number. 13.56 Mhz (high-frequency) tags are usually read/write, they can typically store about 1 to 2 kilbytes of data in addition to their preset (permanent) unique ID number. 860-960 Mhz (ultra-high-frequency) tags are typically read/write and can have … Read more
Below is an example java code to perform Ultralight-C authentication as described in MF0ICU2 / MIFARE Ultralight C – Contactless ticket IC document (chapter 7.5.5 — 3DES Authentication, page 15): public void authenticate(byte[] key) throws CardException { System.out.println(“AUTHENTICATE”); byte[] encRndB = transmitRaw(new byte[] { 0x1A, 0x00 }); if((encRndB.length!=9)||(encRndB[0]!=AF)) { throw new RuntimeException(“Invalid response!”); } encRndB=Arrays.copyOfRange(encRndB, … Read more
With host-based card emulation (HCE) in Android 4.4 you can only emulate the ISO/IEC 14443-4 protocol. More specifically you can only emulate application structures according to ISO/IEC 7816-4 (thus card emulation applications need to be selected though an AID). Moreover, the API doesn’t give you any means to specify if card emulation should be done … Read more
Are serial numbers of NFC tags truely unique? That depends on the tag product and what you consider truely unique. E.g.: ISO 14443 Type A tags with 4 byte serial numbers: There certainly exist duplicates (mainly because there is no clear scheme to divide the available range of serial numbers among the various manufacturers) and … Read more
NFC enabled phones can ONLY read NFC and passive high frequency RFID (HF-RFID). These must be read at an extremely close range, typically a few centimeters. For longer range or any other type of RFID/active RFID, you must use an external reader for handling them with mobile devices. You can get some decent readers from … Read more
The iPhone6/6s/6+ are NOT designed to read passive NFC tags (aka Discovery Mode). There’s a lot of misinformation on this topic, so I thought to provide some tangible info for developers to consider. The lack of NFC tag read support is not because of software but because of hardware. To understand why, you need to … Read more