NTAG424 - Security & product authentication

[hanif_janmohame]

jonathaniglesias 

I am a visual designer (not a developer - hopefully, this is the right place to post ;-) 

I am looking for some help with the NFC portion of an IoT project. I will be working on this project with a small group of students from a CompSci technical college here in Vancouver, BC.

The IoT objects have an embedded NFC Tag and connect the holder to an online platform via their smartphone. The smartphone is geo-located and the holder can post media content. The object is then shared with others, allowing them to connect and post content as well. Physical possession of the object is required to access the platform - it should function as a unique key.

I have built a proof of concept using NFCs with NTAG213 (easily spoofed). I am now looking to develop the prototype a step further using NTAG 424 and SUN messaging to authenticate the object, and provide platform access - without the need for a thin app on the phone - conceptually this seems do-able.

However, this is clearly not as simple as encoding a 213 chip with a URL! I have read some of the material here and elsewhere, and while this seems feasible, I'm sure there are many challenges. I am looking for a bit of enlightenment here - and hopefully, some developer support to help put together a functional prototype. 

 I plan to purchase either HID Omnikey 5022cl or uTrust 3700 F and use the TagXplorer application (Mac/Windows) to encode and test sample NTAG424 NFC Tags. Any other suggestions?

Advice, insight, caveats, and suggestions welcome. Thanks in advance!

[hanif_janmohame]

Hi jonathaniglesias,

Likewise, I hope you are doing well in these crazy times. Thanks for your response and the two datasheets - I will get the students to start here with their exploration, and refer them to this site as well. By 'post content as well' I meant that once the key has been authenticated via the SUN message and the backend, a user can then access the site's content functions via the web browser. Essentially the NFC Tag should act as a validation key, that allows a user to gain access to the full server functions, including posting and viewing content. I have read the material here about the implementation challenges, both of the SUN messaging and on the server, it is quite complex, I trust the students will rise to the challenges here - though I'm sure we will have many more questions as we explore further ;-) Hopefully, they can post them in the user forum. I'm encouraged by the feasibility of the task, in principle and I have ordered an HID Ominkey 5022 as it is listed as supported by TagXplorer. If we are successful with writing to the tag with this combination we can begin our exploration. If you think we would benefit from any additional knowledge resources please do let us know! Thanks.

[Jonathan_Iglesias]

I am sure you and your team will be able to do this project, I think would be better if you have any issue or question we can help let us know here in the community and we will do our best to help. please use the application notes and datasheet from the NTAG 424 as much as possible.

BR

Jonathan 

[hanif_janmohame]

Hi Jonathan,

Earlier I had made an inquiry about the NTG424. I had to put the research aside for a while, and we are now picking up where we left off. I will keep you posted on our progress ;-)

I'm curious about where to purchase physical NTAG424 tags and tokens in a small form factor. I have some sample tags that are very large - 29mm dia. Any suggestions on where to start this process, and where we can acquire them?

Tx.

[Jonathan_Iglesias]

Hi Hanif Janmohamed,

 please contact our partners and manufacturers they sell the Tags on different sizes and materials.

RFID Ecosystem | NXP 

BR

Jonathan

[Jonathan_Iglesias]

Hi Hanif Janmohamed,

Hope you are doing great, I am not sure if " post content as well" do you mean that someone post in social media something using the link? if this is not the case, it seems feasible, you can store a SUN message there. and handle the link using the backend server, so the backend shall know the keys used and  you avoid needing an application  the tag calculates some value and store them in a link then the phone access the link and the server will decrypt and act depending on the information,  you might have some challenges here first is creating the SUN message can be explained in the datasheet and the features and hints application note which explains how to use the features of the tag with examples.

https://www.nxp.com/docs/en/data-sheet/NT4H2421Gx.pdf 

https://www.nxp.com/docs/en/application-note/AN12196.pdf 

the big challenge might be on the implementation of the server, the features and hints have some recommendations.

BR

Jonathan