Hidden surprises in the Bitcoin blockchain and how they are stored (2014)

BTW, please don't use this address-spamming technique! You can simply put data after an OP_RETURN, which, while permanently encoding it in the blockchain, ensures that nodes know it can't be spent.

Re: Hidden surprises in the Bitcoin blockchain and how they are stored (2014)

#5

Post by russellsprouts » Tue, Aug 01, 2017, 7:19 AM UTC

> Along with the standard data, the original transaction also contains the message: 'The Times 03/Jan/2009 Chancellor on brink of second bailout for banks'[3]. Presumably this is a political commentary on Bitcoin compared to the insolvency of "real" banks.

While it may be political commentary, including a headline from a widely known newspaper also proves that the block was created sometime after that date.

Re: Hidden surprises in the Bitcoin blockchain and how they are stored (2014)

#6

Post by 1ba9115454 » Tue, Aug 01, 2017, 7:44 AM UTC

These days getting a 4kb image into the blockchain would cost you around 44 USD.

i.e. 4096 x 200 satoshi fee = 819200 satoshis about .00819200 BTC.

Add approximately a 50% overhead in the way you would need to store that image and you're looking at about .016 BTC.

Re: Hidden surprises in the Bitcoin blockchain and how they are stored (2014)

#7

Post by 1ba9115454 » Tue, Aug 01, 2017, 7:46 AM UTC

RustyRussell wrote: post #4

BTW, please don't use this address-spamming technique! You can simply put data after an OP_RETURN, which, while permanently encoding it in the blockchain, ensures that nodes know it can't be spent.

That's fixed to 80bytes, perhaps space for a few smileys.

Re: Hidden surprises in the Bitcoin blockchain and how they are stored (2014)

#8

Post by Twisell » Tue, Aug 01, 2017, 7:59 AM UTC

Doesn't that mean that a whole blockchain could possibly be deemed illegal in some country due to copyright infringement or other liability of publications laws?

I mean if you can't erase the data and keep publishing it, some would say you are liable.

I see that as a particularly twisted legal argument, but couldn't some country use that against blockchain infrastructure if they feel like it?

Re: Hidden surprises in the Bitcoin blockchain and how they are stored (2014)

#9

Post by zmonx » Tue, Aug 01, 2017, 8:07 AM UTC

Twisell wrote: post #8

Doesn't that mean that a whole blockchain could possibly be deemed illegal in some country due to copyright infringement or other liability of publications laws? I mean if you can't erase the data and keep publishing it, some would say you are liable. I see that as a particularly twisted legal argument, but couldn't some country use that against blockchain infrastructure if they feel like it?

Yes, this is indeed one possible attack vector!

For more information, please see:

https://en.bitcoin.it/wiki/Weaknesses#Illegal_content_in_the...

To quote:

    It is illegal in some countries to possess/distribute certain
    kinds of data. Since arbitrary data can be included in Bitcoin
    transactions, and full Bitcoin nodes must normally have a copy of
    all unspent transactions, this could cause legal
    problems. However, Local node policy generally doesn't permit
    arbitrary data (transactions attempting to embed data re
    non-standard), but steganographic embedding can still be used
    though this generally limits storage to small amounts. Various
    ideas have been proposed to further limit datastorage in the UTXO
    set but are not currently being seriously considered for
    deployment.

Re: Hidden surprises in the Bitcoin blockchain and how they are stored (2014)

#10

Post by Normal_gaussian » Tue, Aug 01, 2017, 8:30 AM UTC

1ba9115454 wrote: post #7

RustyRussell wrote: post #4

BTW, please don't use this address-spamming technique! You can simply put data after an OP_RETURN, which, while permanently encoding it in the blockchain, ensures that nodes know it can't be spent.

That's fixed to 80bytes, perhaps space for a few smileys.

Twit-chain