topic Re: Copying a NTAG 424 DNA without opening the URI in Secure Authentication

Copying a NTAG 424 DNA without opening the URI

gabriele — Mon, 02 Sep 2019 14:53:36 GMT

Hi,

I'm interested in NTAG424 DNA.

I understand that the SUN message is based on URL, UID, and counter, so that the generated string is different each time is read. I guess that the server keep trace of each UIDs' counter.

But what if I copy the string of a DNA tag (without actually opening the link), and paste on a new tag?

That string should still be valid, since the server doesn't know it's been read. The copied link would be valid (just the 1st time is read). Is that correct?

Thank you.

ntag424 #ntag413‌ #ntag 413 dna‌ #cmac‌

Re: Copying a NTAG 424 DNA without opening the URI

Kan_Li — Mon, 09 Sep 2019 07:29:23 GMT

Yes, the server would accept it given the original NTAG 424 DNA was not read again before that time, otherwise the server would detect it.

Have a great day,
Kan

-------------------------------------------------------------------------------
Note:
- If this post answers your question, please click the "Mark Correct" button. Thank you!
- We are following threads for 7 weeks after the last post, later replies are ignored
Please open a new thread and refer to the closed one, if you have a related question at a later point in time.
-------------------------------------------------------------------------------

Re: Copying a NTAG 424 DNA without opening the URI

gabriele — Mon, 09 Sep 2019 07:55:26 GMT

Thank you, Kan.

Have a great day!