Minimum amount of coins per transaction

[JustOne]

Hi,

Similar to a recently asked "max number of coins per transaction" question, I'm asking about the theoretical "min number," for a specific reason. This may have been discussed already but I was unable to find anything in the search results.

Before someone says 1e-8 BTC, I want to know what it would take to send 0 BTC. No tiny numbers at the end. My idea (again, others probably thought of this, too) is to send 0 BTC + Mining Fee to a recipient's address with valuable content in the comments.

The comments could contain valuable plaintext like an order request, a promise to fulfill an agreement and likewise a return agreement (a contract), or it could contain arguments for some add-on protocol. I think there is value in creating public, irreversible communications, like contracts.

Would there be too many problems with this kind of transaction? Should I wait for a BitContract project?

Thanks!

[DannyHamilton]

There is no support for "comments" in the bitcoin protocol.

There is a website (blockchain.info) that maintains their own database of comments for anyone that uses their service, and then publicly displays those comments on their website, but those comments are not stored in the blockchain and are not available outside of the blockchain.info website.

[klintay]

Hi,

Similar to a recently asked "max number of coins per transaction" question, I'm asking about the theoretical "min number," for a specific reason. This may have been discussed already but I was unable to find anything in the search results.

Before someone says 1e-8 BTC, I want to know what it would take to send 0 BTC. No tiny numbers at the end. My idea (again, others probably thought of this, too) is to send 0 BTC + Mining Fee to a recipient's address with valuable content in the comments.

The comments could contain valuable plaintext like an order request, a promise to fulfill an agreement and likewise a return agreement (a contract), or it could contain arguments for some add-on protocol. I think there is value in creating public, irreversible communications, like contracts.

Would there be too many problems with this kind of transaction? Should I wait for a BitContract project?

Thanks!

I think it would waste valuable network speed...it would be like using the btc network for instant messaging.

You can already sign addresses. Then you give the signature+address to the user you want to send the message to, they verify the signature and then they can see the secret message. 

[waldox]

currently the minimum value is 5430 satoshi or 0.00005430 BTC
you may be able to get away with no transaction fee
as there are times transactions get accepted without fees but you may have to wait minutes for the next block to days to get accepted
or if you are a miner, you can create transaction blocks and included them without fees

[heretolearn]

currently the minimum value is 5430 satoshi or 0.00005430 BTC
you may be able to get away with no transaction fee
as there are times transactions get accepted without fees but you may have to wait for the next block to days to get accepted
or if you are a miner and you can create transaction blocks and included them without fees

Is that from the source code ?

[DannyHamilton]

currently the minimum value is 5430 satoshi or 0.00005430 BTC
you may be able to get away with no transaction fee
as there are times transactions get accepted without fees but you may have to wait for the next block to days to get accepted
or if you are a miner and you can create transaction blocks and included them without fees

Is that from the source code ?

The source code of the most recent version of the reference client with a default configuration enforces the 0.00005430 BTC limit on creating and/or relaying transactions.  Therefore, it is quite difficult to get a transaction confirmed (or even seen by most of the network) if the transaction has any outputs that are less than that amount.

However, if you can find a miner (or mining pool) that is willing to accept transactions with smaller outputs, then you can send such transactions.  You just need to make sure that you transmit the transaction directly to the miner (or mining pool) and then wait for that miner (or mining pool) to solve a block.  Once a transaction that pays an outputs less than 0.00005430 BTC is included in a successfully solved block, it will be relayed to the entire network and all wallets will see it.

The default rules on creating or relaying transactions were changed in the most recent version of the reference client, so this "minimum" is not enforced by older versions of wallets.  It is widely expected that the rules will change again with the next version of the reference client as well.

[npiguet]

Are transactions without outputs considered legal? Because if they are, this could be a workaround to the "no outputs can be smaller than 5430" satoshis rule.