Re:How porn links and Ben Bernanke snuck into Bitcoin's code
by DrStalker on Friday May 03, 2013 @12:20AM
(#5648787)
Could you just set up 8 accounts then transfer bitcoins between then, with the chosen recipient indicating the value of a byte?
Obviously it wouldn't be readable to anyone who didn't know what to look for so it couldn't be used for spam/memorials/etc but it could store information.
Re:How porn links and Ben Bernanke snuck into Bitcoin's code
by gizmo686 on Friday May 03, 2013 @01:02AM
(#5648892)
Yes. You could also establish and publish a simple protocol for this, so that someone could run a program and extract all the hidden messages the way we can currently by looking for plain-text. Granted this would provide a means of detecting the messages (and therefore filtering them). This could be counteracted by first posting the data, then posting in the block-chain the fact that you posted the data (along with relevant meta-data). If you do this in a probabilistic way (IE, a single transaction has a 5% chance of being an advertisment of your data), then any would be filter would need to make a trade-off between false-positives, and ease at which a reader could operate.
Also, even when posted in plaintext, I wouldn't say that the messages are readable by people who are not looking for them. (How often do you look at the block chain?)
Unfourtuantly, there is theoretically no way to prevent people from coding arbitrary data into a transaction. Assume you do have a filtering mechanism. It seems obvious that at any point in the block chain, there is at least 2 legal, non-suspisious, transactions. Using just this, Alice can encode 1 bit of information by saying that the first legal transaction is a '0', and the second legal transaction is a '1'. Transactions can be ordered in a deterministic way (for example, look at them as a giant binary number and sort numerically). The psuedo-anonomous nature of bitcoin means that attempting to filter spamming by the source would not work, as you cannot differentiate a new account that is part of a spam attack from a new account that spent at a bad time.