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Service lets you "certify" a document using the Bitcoin blockchain

proofofexistence.com

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Re: Service lets you "certify" a document using the Bitcoin blockchain

#31

Post by randartie »

taway2012 wrote: post #28

Couple questions. 1) AFAIK, bitcoin has "comments" within transactions. Why not embed the checksum as a comment in a transaction between wallets you control? 2) In the approach described here, no coins are being sent with the transaction (right?). Are blockchain participants really accepting NOP transactions involving 0 BTC transfers. Maybe I missed something. 3) As others pointed out, requiring the whole file to be…

1) It might be just doing that actually.

2) 500000 satoshis, as it says on http://www.proofofexistence.com/developers

3) If you are tech savvy, the api lets you send a checksum through a curl to their endpoint. http://www.proofofexistence.com/developers

Re: Service lets you "certify" a document using the Bitcoin blockchain

#32

Post by nwh »

gnerd wrote: post #29
nwh wrote: post #26

Earlier quoted context omitted.

> BitCoin can support 7 transactions per second It doesn't really matter, it's not like they're at all close to that limit. The limit is there to create a market with transaction fees, so it's not just going to be "removed" any time soon.

> The limit is there to create a market with transaction fees, so it's not just going to be "removed" any time soon. The limit is actually there to limit the size of a block. It has nothing to do with transaction fees. Click the link I posted: https://en.bitcoin.it/wiki/Scalability#Current_bottlenecks It used to be 250K and then this year was raised to 1M so it probably will get lifted again. That is the goal of the…

> The limit is actually there to limit the size of a block. It has nothing to do with transaction fees.

Again, the limit is there to create a market with transaction fees. People jostle for space in the block and a market develops around how much people are willing to pay to get into the next block. It's based on the assumption that miners pick the transactions with the highest fees to include in their blocks, which does happen to a certain degree.

Re: Service lets you "certify" a document using the Bitcoin blockchain

#33

Post by clarkmoody »

taway2012 wrote: post #28

Couple questions. 1) AFAIK, bitcoin has "comments" within transactions. Why not embed the checksum as a comment in a transaction between wallets you control? 2) In the approach described here, no coins are being sent with the transaction (right?). Are blockchain participants really accepting NOP transactions involving 0 BTC transfers. Maybe I missed something. 3) As others pointed out, requiring the whole file to be…

1) Comments are enabled as a service by blockchain.info. For details on how the Genesis Block (and comment by Satoshi) was formed, look at the Bitcoin Wiki[1]

2) Coins are being sent. The Developer page says you must send at least 0.00000001 BTC. Edit: actually 500000 Satoshi.

3) Agree. So does the service. See the Developer Page[2]

[1] https://en.bitcoin.it/wiki/Genesis_block

[2] http://www.proofofexistence.com/developers

Re: Service lets you "certify" a document using the Bitcoin blockchain

#34

Post by Buge »

randartie wrote: post #31
taway2012 wrote: post #28

Couple questions. 1) AFAIK, bitcoin has "comments" within transactions. Why not embed the checksum as a comment in a transaction between wallets you control? 2) In the approach described here, no coins are being sent with the transaction (right?). Are blockchain participants really accepting NOP transactions involving 0 BTC transfers. Maybe I missed something. 3) As others pointed out, requiring the whole file to be…

1) It might be just doing that actually. 2) 500000 satoshis, as it says on http://www.proofofexistence.com/developers 3) If you are tech savvy, the api lets you send a checksum through a curl to their endpoint. http://www.proofofexistence.com/developers

2) Those 500000 satoshis are sent to the proofofexistence people and they keep them. In the actual proof transaction only 1 satoshi is sent to each of the proof addresses.

Re: Service lets you "certify" a document using the Bitcoin blockchain

#35

Post by gnerd »

taway2012 wrote: post #28

Couple questions. 1) AFAIK, bitcoin has "comments" within transactions. Why not embed the checksum as a comment in a transaction between wallets you control? 2) In the approach described here, no coins are being sent with the transaction (right?). Are blockchain participants really accepting NOP transactions involving 0 BTC transfers. Maybe I missed something. 3) As others pointed out, requiring the whole file to be…

1) AFAIK BitCoin doesn't have comments[1]. When people have stored data in the blockchain in the past, it was by making a series of transactions in order so later those markers could be decoded to represent something else. Some services allow comments to be layered on top of transactions but that doesn't exist in the blockchain.

2) Money is sent and is rendered unspendable[2] afterwards, so I assume the idea is to send the smallest amount possible (although it seems the service takes a fee).

[1] https://en.bitcoin.it/wiki/Block#Block_structure [2] http://www.proofofexistence.com/about

Re: Service lets you "certify" a document using the Bitcoin blockchain

#36

Post by gnerd »

nwh wrote: post #32
gnerd wrote: post #29

Earlier quoted context omitted.

> The limit is there to create a market with transaction fees, so it's not just going to be "removed" any time soon. The limit is actually there to limit the size of a block. It has nothing to do with transaction fees. Click the link I posted: https://en.bitcoin.it/wiki/Scalability#Current_bottlenecks It used to be 250K and then this year was raised to 1M so it probably will get lifted again. That is the goal of the…

> The limit is actually there to limit the size of a block. It has nothing to do with transaction fees. Again, the limit is there to create a market with transaction fees. People jostle for space in the block and a market develops around how much people are willing to pay to get into the next block. It's based on the assumption that miners pick the transactions with the highest fees to include in their blocks, which…

So then isn't this (or satoshi dice) the sort of thing the limit is trying to create a disincentive for?

Re: Service lets you "certify" a document using the Bitcoin blockchain

#37

Post by spiritplumber »

nwh wrote: post #25
spiritplumber wrote: post #23

Two thoughts. 1) Will this have legal weight? I know that the whole "prove paternity of an invention by sending a certified letter containing the design through the mail, and not opening it until you need it" thing doesn't very much work, if it goes to court you tend to be told "OK, what you say is true in the physical universe, but you did not go through our blessed channels, so nyah nyah nyah". 2) Anything that mak…

> Will this have legal weight? I doubt it. If I have to fax something for it to be a legal document, such an antiquated system will ignore any advances made around it.

Maybe it's because progress is faster, but I see a growing divergence between the physical world and the legal world. I've seen some post-Occupy hearings in which police brutality that had been proven beyond a doubt by video from multiple camera angles was deemed to "not count".

http://opinionator.blogs.nytimes.com/2010/01/11/the-true-ans...

Re: Service lets you "certify" a document using the Bitcoin blockchain

#39

Post by flashmob »

How about miner's fee, is that added to the transaction?

In the About, they say that they make 2 undependable dust transactions.

Would there be any incentive for miners to confirm these transactions and store them in the blockchain? If there's no incentive to confirm the transactions, then the miners might find a way to filter these out of the blockchain.

See also dust transactions:

http://bitcoin.stackexchange.com/questions/10986/what-is-mea...

http://bitcoinfees.com/

Re: Service lets you "certify" a document using the Bitcoin blockchain

#40

Post by delinka »

richardlblair wrote: post #38

So, if I could automate this, could I use this to prove in court that logs were created, and not tampered with? Just trying to think of practical uses of this cool project, and it's the first thing that came to mind.

Yes. Or that a contract was not created before a certain date. Or, as another poster suggested, that a photo of a damaged rental car was taken before you took possession of the car.
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