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Re:Bottle: A Bitcoin SV Browser by Solvitieg on Tuesday June 25, 2019 @04:02PM (#20278262)
If we are posting data to the Bitcoin blockchain, does this data live alongside transaction data? And if so, are there fees to host this data (as we need to pay miners to include data in a block)?
Re:Bottle: A Bitcoin SV Browser by segfaultbuserr on Tuesday June 25, 2019 @04:34PM (#20278616)
> does this data live alongside transaction data?

Yes.

A Bitcoin "transaction" is actually a short Forth-like program running on a stack-based, non-Turing complete virtual machine. When Bitcoin has been sent to an address, the output script of a transaction is something like this:

    let HASH = "xxxxxxxxxxxxxxxxxxxxxx";
    if (check(HASH, pubkey, signature) == True) 
        return 1;
    return 0;
And recall a Bitcoin address is a RIPEMD-160 hash, which means any 20 bytes binary data is a legitimate Bitcoin address. So earliest and simplest method of storing data is simply submitting a payment that sends pennies to a bunch of garbage Bitcoin addresses corresponding to your binary data.

This method was controversial in the early days, as it created a lot of not-actual-transaction garbage in the blockchain. Bitcoin developers later introduced opcode "OP_RETURN", which is seen as a standard and less-evil way to post data. In this case, the script is something like:

    let DATA = "xxxxxxxxxxxxxxxxxxxxxx";
    return 0;
Also, from the perspective of the system, it's just a transaction. Although for a OP_RETURN transaction, it won't be added to the UTXO (unspent transactions) list, because the script always returns false, it's not spendable.

The limitation of using Bitcoin blockchain as a data storage medium is the astronomical transaction fee. The larger the transaction (i.e. the script), the higher the fee. Typically, nobody can afford to store more than a few hundred bytes.

Re:Bottle: A Bitcoin SV Browser by shilch on Tuesday June 25, 2019 @04:52PM (#20278817)
Good summary.

> Bitcoin developers later introduced opcode "OP_RETURN", which is seen as a standard and less-evil way to post data.

This is not true and an error in the Mastering Bitcoin book. OP_RETURN was introduced by Satoshi in the very first version of bitcoin.

> Typically, nobody can afford to store more than a few hundred bytes.

This depends on the artificial constraints put on the network. Bottle operates on top of BSV which comes without a cap on supply and offers cheaper fees when compared to BTC.

Re:Bottle: A Bitcoin SV Browser by onion-soup on Tuesday June 25, 2019 @04:05PM (#20278298)
Yes. It lives as a transaction output under op code 'OP_RETURN'.

See example of weather data stored on chain https://whatsonchain.com/tx/6dac238576e9778458bb62a2f7d936fd...

>are there fees to host this data (as we need to pay miners to include data in a block)?

Yes, current fees are about 1 sat/byte.

This is really a write once, read many type of system.

Re:Bottle: A Bitcoin SV Browser by PowerfulWizard on Tuesday June 25, 2019 @04:18PM (#20278452)
So it will be roughly $115 USD per megabyte? (1% of a BTC). High, but at least you get a 10000x replication factor.
Re:Bottle: A Bitcoin SV Browser by ghostpepper on Tuesday June 25, 2019 @08:30PM (#20280779)
I can see use cases where this would be worthwhile.

Not so much for backing up your photo collection, but more along the lines of publishing some textual information that someone powerful does not want published. It could even potentially function as a sort of notary service.

Re:Bottle: A Bitcoin SV Browser by onion-soup on Tuesday June 25, 2019 @04:33PM (#20278611)
No, it will be around 20 cents to store 1MB
Re:Bottle: A Bitcoin SV Browser by looeee on Tuesday June 25, 2019 @04:08PM (#20278335)
> 1 sat/byte

What's a sat?

Re:Bottle: A Bitcoin SV Browser by Roujo on Tuesday June 25, 2019 @04:13PM (#20278394)
Presumably a Satoshi, the nickname given to the current smallest fraction of a bitcoin that is recorded on the block chain - 0.00000001 BTC.

https://en.bitcoin.it/wiki/Satoshi_(unit)

Re:Bottle: A Bitcoin SV Browser by solotronics on Tuesday June 25, 2019 @04:11PM (#20278376)
1 satoshi = smallest current unit of a bitcoin = 0.00000001฿
Re:Bottle: A Bitcoin SV Browser by onion-soup on Tuesday June 25, 2019 @04:11PM (#20278377)
1 satoshi per byte. 1 satoshi = 0.00000001 BSV
Re:Bottle: A Bitcoin SV Browser by cocktailpeanuts on Tuesday June 25, 2019 @04:04PM (#20278293)
i think all these things we're looking at in the browser are stored as transactions using some clever protocol scheme.

Fell down the rabbit hole and found these:

https://b.bitdb.network

https://c.bitdb.network

https://bit.planaria.network

Re:Bottle: A Bitcoin SV Browser by musicious on Tuesday June 25, 2019 @04:05PM (#20278302)
Yes.. the data is included in the OP RETURN field. You pay 1 Satoshi per byte. For now that's the minimum relay fee.