FlexDF vs FlexNT What Are The Differences?

Ok, I did a bit more research and apparently my office is using HID iCLASS SE R10 readers (https://www.hidglobal.com/products/readers/iclass-se/r10). They list compatibility with MIFARE Classic and DESFire EV1. Specifically, the listed card compatibility includes:

Secure Identity Object™ (SIO) on iCLASS Seos, iCLASS SE/SR, MIFARE DESFire EV1 and MIFARE Classic (On by Default)

  • MIFARE Classic and MIFARE DESFire EV1 custom data models
  • standard iCLASS Access Control Application (order with Standard interpreter)
  • ISO14443A (MIFARE) CSN, ISO14443B CSN, ISO15693 CSN
  • FeliCa™4 CSN, CEPAS4 CSN or CAN

So it seems like the FlexNT (which I was planning to get) won’t work. Correct?

I know the FlexDF will work for DESFire EV1.

Would the new xDF2 work also? I like the 8kB capacity of this tag, and the fact that it’s newer, so theoretically more future-proof (I don’t want to have to “rip and replace” in the future). It seems to be backward compatible with DESFire EV1, per the NXP datasheet, which states that it “… is fully interoperable with existing NFC readers for MIFARE products” so I assume I’d be good. Also, seems like anything using 13.56MHz has read range issues when it’s a cylinder rather than a flat Flex tag. So I may want to go with the FlexDF instead for that reason, right? Or is a FlexDF2 in the works??

The proposed FlexM4+ would seem to work because of the MIFARE Classic compatibility as well. But doesn’t “Classic” mean “soon to be obsolete?”

Man. I really thought I had this all figured out. I was going to get a FlexNT and be able to work with most things, including my phone and access systems. But one of the main reasons to get it was my office. And it doesn’t seem like it will work for that. So, I’d love input on this. Maybe I should just get tags embedded all up and down my forearms. That way I can just run my arm past any reader and assume that at least one of the tags is compatible!! Just kidding. …or am I?

In short, I think your best bet is to try a flexDF or xDF2 chip with your system. You will need to go through a process called “enrollment” which basically defines the applications on the DESFire chip necessary for access control. The EV1 chip requires that the master key be used to do this, which very likely means that a factory default DESFire EV1 chip in the flexDF will be totally and forever dedicated to that access control application. The EV2 chip allows sub-keys to be defined which allow applications to exist side by side without needing to divulge the master key, but that is a complex process and of little value for access control systems who are used to dedicating the entire chip to that one application.

I can say there may be options coming for the VivoKey Flex One for side-by-side applications, including HID, but this is still a long ways off at this point.

I would get DESFire EV1 and DESFire EV2 based cards from Amazon or somewhere and test with those first… see how the system programs them, and if the system leaves any room on the chip for other applications (like NFC NDEF data).

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https://forum.dangerousthings.com/t/xm1-relaunch-or-alternative-elsewhere

I’m tinkering…

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