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Child abuse images hidden in crypto-currency block chain

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Re: Child abuse images hidden in crypto-currency block chain

#41

Aren't we getting back to the hypothetical question that any image, digitally encoded, would theoretically exist at some index of any infinite number (e.g. Pi), given enough digits? Is the possession of Pi then illegal?

No, because the law doesn't work on the principle of mathematical technicalities and possibilities, it attempts to work on the principle of reason. The question you should really be asking is whether a judge would deem that to be illegal and the answer is almost certainly "no".

Re: Child abuse images hidden in crypto-currency block chain

#42

> He said there was "ongoing research" to find ways to remove such content from block chains but these were "not yet mature". Either you have centralization, which nobody wants, or you have a bot that everyone agrees on to censor things, and people will will always find ways around bots. Are there really any other alternatives?

One possible alternative, with its own drawbacks, is no censorship at all.

Re: Child abuse images hidden in crypto-currency block chain

#43
post #25
post #5

Possession of this type of image is a federal crime in the US.[1] When I took a digital forensics course about five years ago, we were told that if we ever discovered any on a system we were investigating, it needed to be reported to the FBI immediately or we could also be charged. If someone does this in a way that goes unnoticed, and it's discovered after long enough that rolling back is impractical, does that effe…

Related: What's the smallest piece of data that qualifies? Can a 16x16 image be illegal? What about a 64x64 image? What's the situation like if you have two chunks of data (perhaps at two separate locations on the blockchain) and only if you XOR them you get the illegal image?

> Can a 16x16 image be illegal?

In theory yes, in practice probably not.

> What about a 64x64 image?

In theory yes, in practice probably not.

> What's the situation like if you have two chunks of data ...

Almost definitely illegal.

Re: Child abuse images hidden in crypto-currency block chain

#45
post #18

So, the easiest for the government to destroy blockchain is to supplant their own illegal images onto the blockchain themselves...

No, the easiest for the government to destroy blockchain is to just declare it illegal.

Do you seriously think that will be effective? Have you never heard of marijuana?

Re: Child abuse images hidden in crypto-currency block chain

#46
post #28
post #12

Ah, this old chestnut. So from the last time this came up: https://thebitcoinnews.com/no-there-isnt-child-porn-on-the-b... With the important bit here: 80 bytes is all that OP_RETURN can store, and what’s more that information is subject to deletion. That’s because bitcoin nodes are capable of pruning “provably unspendable” UTXOs for efficiency, which include OP_RETURN data. TL;DR the last time the schadenfreudists w…

Following links from the article: https://blog.moneybutton.com/2019/01/26/how-we-added-support... https://www.yours.org/content/the-unfuckening-of-op_return-b... " We’re about to take the red pill and see how deep the rabbit hole of on chain data storage really goes. Tokenized is ready for this, yours.org is ready for this, @_unwriter and his plethora of tools are ready for this as are others. Calvin Ayre has previou…

Yep, so it is OP_RETURN and therefore can and will be pruned.

Re: Child abuse images hidden in crypto-currency block chain

#47
post #25
post #5

Possession of this type of image is a federal crime in the US.[1] When I took a digital forensics course about five years ago, we were told that if we ever discovered any on a system we were investigating, it needed to be reported to the FBI immediately or we could also be charged. If someone does this in a way that goes unnoticed, and it's discovered after long enough that rolling back is impractical, does that effe…

Related: What's the smallest piece of data that qualifies? Can a 16x16 image be illegal? What about a 64x64 image? What's the situation like if you have two chunks of data (perhaps at two separate locations on the blockchain) and only if you XOR them you get the illegal image?

> What's the situation like if you have two chunks of data (perhaps at two separate locations on the blockchain) and only if you XOR them you get the illegal image?

That's an interesting legal question and there's also already a content publishing system (Publius) that afaik uses a similar approach: https://en.wikipedia.org/wiki/Publius_(publishing_system)

Let's assume person A publishes 1 MiB of random data on their web server. Afterwards person B XORs illegal content against that data and publishes the result on their own web server (which to an outsider looks like random data). A's file XORed to B's file re-creates that illegal content.

Let's assume that at a later point it's not possible anymore to determine who published their file first. Who is liable for the illegal content? And who needs to remove that data from their server? Neither of them? Both of them? The first variant definitely sounds wrong, but the second variant implies that you can get in trouble for publishing perfectly random data.

Re: Child abuse images hidden in crypto-currency block chain

#48
post #32

> He said there was "ongoing research" to find ways to remove such content from block chains but these were "not yet mature". Either you have centralization, which nobody wants, or you have a bot that everyone agrees on to censor things, and people will will always find ways around bots. Are there really any other alternatives?

The easiest solution is probably just limiting how much data you can add to the ledger. There's no real reason why people need to add more than 10kb of information to a transaction. Cryptocurrencies aren't meant to be image hosting platforms anyway.

Images can be split into 10kb blobs...

Re: Child abuse images hidden in crypto-currency block chain

#49
post #25

Earlier quoted context omitted.

Related: What's the smallest piece of data that qualifies? Can a 16x16 image be illegal? What about a 64x64 image? What's the situation like if you have two chunks of data (perhaps at two separate locations on the blockchain) and only if you XOR them you get the illegal image?

Taking your last step further: Is any half illegal? Or only the one created at a later date? Reminds me of the library of babel https://libraryofbabel.info/bookmark.cgi?wvlbf.j,qkfjo,wpyrd...

Well either half is utterly meaningless without the other, and could actually be arbitrary, right? So you'd have to have them both together for it to be illegal.

Re: Child abuse images hidden in crypto-currency block chain

#50

Aren't we getting back to the hypothetical question that any image, digitally encoded, would theoretically exist at some index of any infinite number (e.g. Pi), given enough digits? Is the possession of Pi then illegal?

Very far-off digits of π (assuming π is even a normal number) are not easily accessed or enumerated. In fact, you'd probably need more information to encode the index and length of your sequence than you would to just write the data out. In contrast, a block chain is easily downloaded and traversed, indices are small, and most importantly, there is a very, very obvious intent to distribute illegal content. I don't th…

"The Bailey–Borwein–Plouffe formula (BBP formula) is a spigot algorithm for computing the nth binary digit of the mathematical constant π using base-16 representation. The formula can directly calculate the value of any given digit of π without calculating the preceding digits. (...) Though the BBP formula can directly calculate the value of any given digit of π with less computational effort than formulas that must calculate all intervening digits, BBP remains linearithmic (O(n log n)), whereby successively larger values of n require increasingly more time to calculate; that is, the "further out" a digit is, the longer it takes BBP to calculate it, just like the standard π-computing algorithms."

https://en.wikipedia.org/wiki/Bailey%E2%80%93Borwein%E2%80%9...

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