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Re:Random Mosaic – Detecting unauthorized physical access wi... by leakycap on Tuesday September 23, 2025 @02:11PM (#45350762)
I would have never come across this except on HN & it's awesome!
Re:Random Mosaic – Detecting unauthorized physical access wi... by extraduder_ire on Thursday September 25, 2025 @09:04AM (#45372210)
I first learned about it via the blink comparison app on f-droid, linked in the article.
Re:Random Mosaic – Detecting unauthorized physical access wi... by gus_massa on Tuesday September 23, 2025 @09:28PM (#45355143)
Old discussion https://news.ycombinator.com/item?id=31897530 (642 points | June 2022 | 165 comments)
Re:Random Mosaic – Detecting unauthorized physical access wi... by metalman on Thursday September 25, 2025 @07:39AM (#45371671)
there is I believ a similar thing useing paint spatters as idicators of authentisity of electronics and also as proof of tampering, as the patterns are unique and can be produced, recorded ,quickly and cheeply.
Re:Random Mosaic – Detecting unauthorized physical access wi... by flir on Thursday September 25, 2025 @07:47AM (#45371727)
Much like the split tally stick: https://en.wikipedia.org/wiki/Tally_stick
Re:Random Mosaic – Detecting unauthorized physical access wi... by zahlman on Thursday September 25, 2025 @10:37AM (#45373119)
> If of one or more elements within the mosaic are modified, unauthorized access or compromise can be assumed.

... But how is the recipient certain of what the mosaic should be? You can't put the reference photo in the same package, because it's taken after sealing. And if you send it separately, that package is also subject to tampering.

Re:Random Mosaic – Detecting unauthorized physical access wi... by jrm4 on Thursday September 25, 2025 @11:39AM (#45374130)
um, you like text it or email it?
Re:Random Mosaic – Detecting unauthorized physical access wi... by ZeWaka on Thursday September 25, 2025 @01:18PM (#45375784)
> ...an original photo, which has been taken for example, by a manufacturer, signed and transmitted to a customer via an encrypted communication channel, with a photo of the current state.
Re:Random Mosaic – Detecting unauthorized physical access wi... by zahlman on Thursday September 25, 2025 @01:39PM (#45376147)
Thanks, glossed over that, and also should have thought of it.
Re:Random Mosaic – Detecting unauthorized physical access wi... by FuriouslyAdrift on Thursday September 25, 2025 @10:49AM (#45373288)
Chaos Computer Club talk on this (using glitter nail polish) from way back in 2014...

https://www.youtube.com/watch?v=zpFKeVuP0_w

The talk covers A LOT more and focusing on "evil maid" attacks.

Re:Random Mosaic – Detecting unauthorized physical access wi... by ape4 on Thursday September 25, 2025 @11:17AM (#45373756)
The article anonymized a face using the compromised swirl method
Re:Random Mosaic – Detecting unauthorized physical access wi... by Katzenmann on Thursday September 25, 2025 @11:20AM (#45373798)
Yeah but it looks like the face was also blurred before the swirl
Re:Random Mosaic – Detecting unauthorized physical access wi... by vpribish on Thursday September 25, 2025 @01:47PM (#45376263)
"The rice is a little more fine-grained"

nice writeup!

Re:Random Mosaic – Detecting unauthorized physical access wi... by Timwi on Friday September 26, 2025 @05:49PM (#45391360)
It's a cool idea but it kind of bothers me that with all this effort, you still only get a boolean worth of information (it was either accessed or not). No clue about who, when, where or why.