Linked Questions
15 questions linked to/from Explanation of what an OP_RETURN transaction looks like
34
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3
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Why does Bitcoin use two hash functions (SHA-256 and RIPEMD-160) to create an address?
Why do we use 2 hash functions (both SHA and RIPEMD) to create an address? Why not just use one hash function?
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5
votes
1
answer
8k
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How does a blockchain store any data?
I read here that since Bitcoin is a networked ledger, it is a good way to back up data. I would like to know two things:
How does a blockchain store 'any' data? I would like to know more about a ...
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4
votes
2
answers
2k
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Why would a miner put an OP_RETURN in a coinbase transaction?
I’m looking at this coinbase transaction. I'm confused why there are two outputs and why one of them is labelled with OP_RETURN.
- 1,720
9
votes
4
answers
1k
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Is there a listing of strange or unusual scripts found in transactions?
I'm studying scripts and am looking for strange or unusual scripts that have appeared in any of the *coin networks..(outside the standard ones listed on this page)
Is any one person, or website ...
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0
votes
1
answer
1k
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Why OP_RETURN should be used instead of raw data?
I've read this great Explanation of what an OP_RETURN transaction looks like and now I have only one question. Imagine that someone want to store some data in Bitcoin's blockchain. Why should he use ...
- 337
0
votes
3
answers
547
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Pictures and non-transaction data in block chain
It is well known that non transaction related information has found its way into the block chain. This raises multiple questions: (1) How was it done, and is it still possible (2) If someone where to ...
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3
votes
1
answer
418
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Does an OP_RETURN script always need another output within the transaction?
I was reading this:
Explanation of what an OP_RETURN transaction looks like
and I wondered if the second output "value" : 0.00200000, was at all necessary. Can I just have a OP_RETURN with a 0 output ...
- 155
2
votes
1
answer
415
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Upper bound on the Bitcoin transaction size [duplicate]
Assume that I want to store some arbitrary data on the Bitcoin blockchain via a single transaction.
Question: Is there any upper bound on the size of data I want to send via a single transaction?
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- 291
2
votes
1
answer
227
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Question regarding the number of bytes in an OP_RETURN transaction
I was reading this very useful explanation of what an OP_RETURN transaction looks like and got tripped up by part of it.
"hex" : "6a13636861726c6579206c6f766573206865696469"
This first ...
0
votes
1
answer
112
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Hiding data in OP_RETURN statement?
I'm reading this article, and quote
The blockchain transaction’s OP_RETURN data can be decrypted using AES-256 GCM to provide a backup command and control domain name
How did someone able to ...
- 107
0
votes
1
answer
98
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Proving the margin of error of a block timestamp
In the Bitcoin wiki:
Block times are accurate only to within an hour or two.
is a bit vague. Is it possible to prove that an arbitrary accepted block timestamp is within x seconds of the real-...
- 121
0
votes
1
answer
70
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Can a client leave its mark on the blockchain?
Would it be possible for a client (eg the core client) to leave its mark in the form of META data on the blockchain or even in the mempool so that we know that this client was used to create or send ...
- 1,366
0
votes
2
answers
69
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Only My Transaction in a block
I am thinking of broadcasting a Bitcoin transaction with a very important message. The message is so important that I want it to be the only transaction (other than coinbase) in the block.
For example ...
0
votes
1
answer
37
views
Additional instructions in TX
Would it be possibile to add additional information in TX?
I would like to add time of transaction in it.
Would hash of TX change if hostile node would change that time ?
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0
votes
0
answers
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Getting Started with a Hello World Node.js App making an API call to bitcoin.org
I have been reading around trying to find where/how you can attach a SHA256 or MD5 hash (i.e. a small chunk of data) to a Bitcoin transaction, which led to OP_RETURN, but I have yet to see exactly how ...
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