Topic: CryptoGraffiti - Block Chain Message Encoder & Decoder - page 8. (Read 35470 times)

Of course, but perhaps we can replace old pointers to transactions in the blockchain with new pointers.

For example, I write a graffiti "I Love Lucy." Then I stop loving Lucy and start loving Linda. I make a new graffiti "I Love Linda" and replace the old "I Love..." graffiti with the new one (in CryptoGraffiti, not the blockchain).

Bitcoin address in its raw format contains 20 bytes of data. These 20 bytes are later converted into base58 and a checksum is appended, thus we get a typical bitcoin receiving address. To decode an address I restore the underlying 20 bytes from the bitcoin address and seek common ASCII characters from it. If more than 90% of the characters are visible ASCII characters then the address is assumed to be human constructed and thus is probably a human readable text.

What exactly is the format used for encoding? ASCII encoded in base58 format (minus the version, and the checksum)?

You cannot edit anything that has been saved in the block chain unless you control more than 50% of the network's hashing power.

Very cool! Is this a Twitter on the blockchain? Are there possible ways to permit editing messages already sent?

We're currently working on a new GUI so the month being off issue should be resolved soon. I am not aware of an automated way to build transactions out of addresses but we're planning to implement automated message sending soon so internally we would have to develop such system.

Cool project!

Things I found:
- the month seems to be one month off (it's still September instead of October)
- In Google Chrome on Windows when pressing "select all" addresses in list mode the addresses do not have line breaks which makes further processing quite hard as there is no separator between the addresses. Works on Firefox though...

Is there a good, preferably automated, way to build transactions out of the addresses? So far I have been using brainwallet.org but it gets cumbersome after a while and you can spend hours adding addresses...

True, RAM indeed is a problem. I have to regularly restart one of my stationary laptops that runs bitcoin-core because it crashes after a week of uptime, throwing some system error. If the number of unconfirmed transactions becomes too big or starts taking too much memory then why not put that in a file too?


Yes, I also suggested that idea to the PeerCoin community. However, if you think about it, sending a small TX once in a year to your cold storage addresses is really not that difficult. You would obviously check your cold storage anyway to see whether it is still there and intact. If a year is too short time then make it 5 years. The point is not to penalize cold storages but to prune unspendable dust transactions.

The min transaction fees help, but as I understand it right now the UXTO is kept in RAM on pretty much all implementations, whereas the blockchain (the thing polluted by gambling sites) is stored on disk. So the issue is that RAM is far more expensive/scarce than disk space, and the addresses you generate will be stored indefinitely in RAM on all clients (assuming clients don't figure out how to prune them).


I think such a big change would be very controversial in the Bitcoin community. A lot of people like the idea that you can store coins on a paper wallet and know that you could come back to it 10 years later without any "maintenance".

I don't see a problem here. We have minimum output size and transaction fees in place to prevent dust transactions and malicious spam. Satoshi Dice and services like that are more of a problem than proof of existence. Things may change for the better when Open Transaction gets implemented. Alternatively, such messages can also be stored in other block chains. I have plans to integrate DogeCoin and some others in the future. Also, I'd like to emphasize that CryptoGraffiti was initially designed to archive the already stored messages in hope of discovering some hidden secrets. Even if I disabled the write functionality, it would still be trivial to write a custom message into the block chain.

About block chain pruning, even if it is programmatically possible to analyse the transaction outputs and delete outputs with low enough entropy, the messages could just be compressed as a zlib stream (which I have planned to implement in the future).

However, here's an idea that just came to my mind: outputs that have not received a transaction for 1 year should gradually lose their bitcoins (demurrage). If the address represents a cold storage, its owner should at least once in a year send a dust transaction to their cold storage addresses so that demurrage wouldn't apply.  If you have some important proof of existence stored in the block chain, you should also make sure to send dust transactions to it so that it wouldn't be affected by demurrage and thus be eventually pruned.

Won't that create huge costs for the rest of the network if this service became widely used? Isn't uxto space one of the most scarce resources right now?

I don't think the community would want that. The Bitcoin Core is meant to carry only the basic functionality that is needed for the network to operate. Unfortunately the devs went rogue already and implemented HTTPS and some payment request crap so even the bitcoin is slowly becoming bloatware. I don't want to contribute to turning Bitcoin-core into even more bloatware.


It is similar and cryptograffiti can be used the same way actually, except currently cryptograffiti is all manual so that the user needs to make an appropriate transaction for the data to be saved in the block chain. Cryptograffiti is free while proofofexistence charges some money.

Is it similar to www.proofofexistence.com?

On CryptoGrafitti matters, what is preventing you from adding such functionality to Bitcoin wallet itself?

That's true.

Am I correct in assuming that with messages like this one (#1125) https://blockchain.info/tx/cc38d740dc1999a803dbba0c48a82af994861e0767f6bcd7d6ceebe4e66b4678



it's the case that these outputs can never be spent and therefore they have to remain in the utxo (unspent transaction output) set permanently?

Well, if you hash a message with SHA256, you'll get a private key of with you can generate a public key (bitaddress.org)
When you send some satoshis to that address, it is locked in the blockchain but nowbody knows the message yet.
Basically it is the same as a brainwallet.

I don't know about the message in a label because I never used it but since it is visible it works differently

Chris Ellis on cryptograffiti

http://youtu.be/0o4XyTAuQIQ?t=23m3s

In which ways is it different than making a transaction and putting the text in a label? If I'm not mistaken both are inside the blockchain

Wow, I was looking for something like this!
I'm definitely going to do this.
I want to make some predictions about the future and store my will in the blockchain!