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Every V4 UUID

everyuuid.com

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Re: Every V4 UUID

#271

Post by aidenn0 »

lxgr wrote: post #234
dhosek wrote: post #232

Earlier quoted context omitted.

My favorite of these was a trick where someone picked a card out of a deck and then Teller revealed a large version of that same card in an unexpected area in the vicinity, It turns out that what he had done was hide a complete set of large cards in the area before the trick and memorized the location of every one of them so, e.g., the king of hearts would be at the top of a palm tree, the three of spades under a dri…

The best part is that that kind of trick usually becomes more, rather than less, impressive when its inner working is revealed. I recently got to see them perform live, and my favorite trick by far was one of that kind.

There was a video of a magic trick I saw where the trick was almost certainly accomplished by false shuffles. I know how to do a few false shuffles, in theory, but, the magician (Ricky Jay, I think?) was just so good at the false shuffles that I was more impressed than if I didn't know how it was done.

Re: Every V4 UUID

#272

Post by eieio »

thaumasiotes wrote: post #219
eieio wrote: post #69

Earlier quoted context omitted.

I'm really happy that the trick was magical to you - I was so surprised and delighted when I realized that this was possible, and I wasn't really sure if anyone else would feel the same way! And of course, I'm proud to be providing so much utility here - finally we can find and use UUIDs tailor-fit to our needs

> If we didn’t care about generating valid UUID v4s, we could just generate 2^128 numbers, scramble them, convert the resulting bits into a hex string, and intersperse some dashes. You can do that anyway. You'd only need the twiddling if you wanted to limit the amount of numbers you generate to 2^122. Since you're willing to generate 128 bits: // get encrypted value uint128 bits = encipher(seed); // clear zero bits b…

I considered this, but I'd just be so unsatisfied if I finished scrolling through all 2^128 rows and realized I'd seen some duplicates!

Re: Every V4 UUID

#273

Post by eieio »

kittoes wrote: post #211
eieio wrote: post #157

Earlier quoted context omitted.

FWIW I am super interested in this question but feel like I don't know how to derive a satisfying answer, maybe because the one of my goals here (add "enough" entropy) is a real fuzzy "I know it when I see it" sort of thing. But I'm gonna try to get a few more crypto-knowledgeable friends to chat with me about this and write up what I learn!

You've sniped me and I'm going to try and tackle this over the weekend. What's the best way to exchange things for you? Also, have you explored modular multiplicative inverses at all?

eieiogames@gmail.com is great (or whatever's best for you on https://eieio.games/whats-my-deal)

I think the biggest rabbit hole I went down was trying to use FEAL (which is very breakable) and exploiting the things that make it breakable. But this is very much not my area of expertise - I was learning as I was working - so it's very possible either that that was a dumb idea or that it was a great idea that I didn't figure out.

I also considered things like "focus on add lots of entropy to groups of 200 or so UUIDs, but have obvious patterns beyond that" which I think would be a reasonable strategy; here I just kind of ran out of time (I told myself I'd make this in a week)

Did some light reading about a few other things but nothing substantial

Re: Every V4 UUID

#274

Post by Dylan16807 »

saagarjha wrote: post #260
Dylan16807 wrote: post #255

Earlier quoted context omitted.

Are you suggesting we should never have made the random one, and stuck with mac address plus timestamp forever?

I actually believe we shouldn't have made any of them

Oh okay. That's a pretty different suggestion from the comic.

Would you suggest random 128 bit numbers, then? Otherwise it's hard to see what else would serve the same role without being UUID in a trenchcoat. And having identifiers is important.

Re: Every V4 UUID

#275

Post by [deleted] »

lilyball wrote: post #105
tobyjsullivan wrote: post #21

The fact that the search works impressed me more than anything. Of course, like every great magic trick, it seems so simple once it is explained. For the curious, here's the linked blog post describing how the project works: https://eieio.games/blog/writing-down-every-uuid/ Edit to add: I'd only tried searching for an exact UUID when I wrote this comment. I didn't realize it supports full text search! Now I'm even mo…

The explanation for full-text search was actually slightly more intelligent than what I initially assumed. I figured it just generated UUIDs until it found one that was in the correct direction of search (for the next/previous button), since I had observed that walking forwards and backwards in search results was giving different results each time, but in fact the author did the slightly better thing which is to just…

[deleted]

Re: Every V4 UUID

#278

Post by vivzkestrel »

tobyjsullivan wrote: post #21

The fact that the search works impressed me more than anything. Of course, like every great magic trick, it seems so simple once it is explained. For the curious, here's the linked blog post describing how the project works: https://eieio.games/blog/writing-down-every-uuid/ Edit to add: I'd only tried searching for an exact UUID when I wrote this comment. I didn't realize it supports full text search! Now I'm even mo…

For the even more curious, UUID has 5316 decillion 911 nonillion 983 octillion 139 septillion 663 sextillion 491 quintillion 615 quadrillion 228 trillion 214 billion 121 million 397 thousand 304 values. Imagine the fact that there aren't as many kms to reach GN-Z11 (farthest known galaxy in the Universe I think) as there are digits above

Re: Every V4 UUID

#279

Post by thaumasiotes »

sameoldtune wrote: post #104
InsideOutSanta wrote: post #65

Earlier quoted context omitted.

Yeah, I at first, I though I knew exactly how it worked. Then I saw the search field, and I suddenly had no idea what the hell was going on. Now, the big question, do I want to spoil the magic trick and read how this was done, or should I keep being astonished and flabbergasted?

I disagree with my sibling comment. The trick is beautiful. If you generate UUIDs such that each bit in the result can be reliably traced back to a single bit in the input, then you can take a substring of the UUID and use that to infer which bits of the input integer must be set to produce that substring. So you can produce a whole list of input bytes that meet the criteria and those become your search results. The…

> I disagree with my sibling comment. The trick is beautiful. If you generate UUIDs such that each bit in the result can be reliably traced back to a single bit in the input, then you can take a substring of the UUID and use that to infer which bits of the input integer must be set to produce that substring.

...but that has nothing to do with what the website is doing. The accompanying article specifically calls out the fact that it can't be done while maintaining the appearance of an unordered list, and therefore it isn't attempted.

Re: Every V4 UUID

#280

Post by kshri24 »

cubefox wrote: post #205
lxgr wrote: post #142

Earlier quoted context omitted.

Memorable UUIDs? I think you're on to something here! (Also, dibs on 00000000-0000-4321-abcd-000000000001!)

The most offensive sentence I could come up with leetspeak/hexspeak is this one: fe11a710-babe-4150-ace5-b19b1accd1cc (Yes it's a valid UUID) (I am so sorry)

Got the rest but what is ace5? Aces?
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