New answers tagged blockchain
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A valid Bitcoin block has to include a minimum of one transaction, which is the coinbase transaction that pays out the block reward. Most of the early Bitcoin blocks did not include transactions that sent bitcoins from one party to other, but included only the coinbase transaction that paid out the newly minted bitcoins.
In fact, the first transaction ...
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When a miner solves a block, they must include a Coinbase transaction. The Coinbase transaction is unique in the block and pays out the block reward to the miner's address. In order to redirect the block reward, an attacker would have to change the Coinbase transaction. Since all transactions are committed to via the Merkle tree that resulted in the Merkle ...
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Entirely depends on the exchange. In previous exchange hacks, users have been compensated in creative ways, sometimes the exchange takes the hit from some sort of emergency fund. That, however is not an indication of what might happen in the future.
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If the transaction outputs associated to the public key has not been spent, then finding the funds associated with that public key will mostly be a trial and error method.
Searching in outputs
Most outputs in Bitcoin send funds to an address that is the hash of the public key. Pay-to-public-key (P2PK) is the only standard output that sends funds directly ...
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In order to spend funds, you need to create a signature corresponding to the address that the funds previously got paid to. This requires the private key from which the address was derived. According to your information, this private key is held by Coinbase. Thus, you'll need to get Coinbase to help you, nobody else can.
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Talk to Coinbase Support center they will surely help you because it's impossible to transfer your credit without there help
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In fact, the usual way to consult blockchains is using the public key (purportedly the public key of the searcher) as the result will be all the transactions in which the key is involved:
https://www.blockchain.com/btc/address/1EwpnNBdFJykwxp6X8v9AfZnup9bgmrLE1
I suppose you're puzzled about the way to convert the public key to the public address, as the ...
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You can use the -prune command when you execute the core. This will strip down the blocks your client maintains to only the essential. For me it has pared down the size of the btc Blocks folder by a third.
Add -prune to the end of your command line when you go to run the bitcoincore executable
All command-line options (except for -conf) may be ...
1
the coin is gone from the sending wallet yet never arrived in the receiving wallet.
Although we often say (or write) that coins are stored in wallets, it is important to remember this is just a convenient shorthand analogy for communication between people.
In reality, Bitcoins don't exist in wallets, they are not stored in wallets and are not moved in and ...
2
the coin is gone from the sending wallet yet never arrived in the receiving wallet
This isn't really a thing - The transaction is confirmed, which means the coins did move. In fact, the 0.0215682 sent has already been spent (I am assuming that is the payment amount, as the other output goes to a p2pkh address, which seems likely for a change output), which ...
7
You probably could - blockchain.info has certainly taken steps towards letting you, and provide a reasonably complete API, along with websocket streams for real time data.
That said, you probably shouldn't - Bitcoin, and other cryptocurrencies, are designed to be decentralized and trustless. By using Blockchain.info, or any other API provider, you leave ...
0
The R value is the result of EC point multiplication between the k value (known as the nonce) and the secp256k1 curve's generator point. It is effectively the public key for k. The only way that an R value can repeat is if k is also the same. Given that k is a 256 bit number and is supposed to be chosen completely randomly, k should not repeat unless the ...
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You need to install a bitcoin full node, then create a program to scan from latest block to first block all the unspent outputs and keep in memory, maybe in something like Redis, the status of the balances of the addresses until you reach the 1 million you are looking for
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Insight Block Explorer is the program. It has an API you can query.
You'll need to install the block explorer. It runs in a nodejs environment.
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Take at a look at this program. It will dump the entire current UTXO database to a CSV file that you can crossreference. https://github.com/in3rsha/bitcoin-utxo-dump
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I prefer www.payb.tc this is getting small percentage only. No additional fees.
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If you create two transactions that use some of the same UTXO as inputs, every node will perceive only one of them as valid. By default, this will be the one that nodes first see: once a node learns about a transaction, it considers the UTXO used in the inputs to be spent from the perspective of the mempool. When the node sees the second transaction, it ...
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Addition to Bolton's answer: Transactions in a block can be in any order, given that if a transaction spends another's output, the parent transaction must come before the child tx and the coinbase transaction (collecting the block reward) comes first.
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Bitcoin and other blockchain protocols enforce the constraint that any valid chain cannot have double spend UTXOs. If a miner were to include two transactions in a block both spending the same UTXO, the entire block would be invalid, and no other nodes in the network would accept it. If you were to create two transactions from the same UTXO and send them ...
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If by individual you mean users I would argue the contrary as many wallet are SPV based or have a centralised backend running a full node (form of lightness as any client does not run a fullnode).Only few desktop bitcoin wallet such as bitcoin core or armory run as fullnode. Fullnode are necessary for miner but it's still good for anyone to run it as it does ...
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What i'm asking is, does the contents -transactions- of one block effect the hash of the next block? if so, how it happens?
Yes. The block hash of block X is explicitly included in the header of block X+1. So if you change the transactions in block X, it will affect the hash of block X, and that would change block X +1 as well.
For example, lets say ...
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These websites https://goochain.net/ or https://blockchair.com/ allow you to query by dates the bitcoin blockchain
-1
I would say that a Dust Attack on Bitcoin is the most dangerous system that hackers use to steal Bitcoin. According to this article:
https://dust-attack.blogspot.com/2019/03/blog-post.html?m=1
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Because r only depends on the random number k (in addition to curve parameters) and reusing k, as long as the private keys are different, is OK.
Further reading: https://www.maximintegrated.com/en/app-notes/index.mvp/id/5767
4
Everything MCCCS wrote is good, but just to clarify on your last question:
How many nodes must approve/verify the winning hash before it is accepted into the bitcoin network as the next block to be added?
This question is slightly misguided: there is no 'accepting a block into the bitcoin network', because this assumes there is some network-wide ...
3
3: Each node has its own mempool. Each node validates the new transactions that they receive when they receive.
4-5-6: Nodes don't mine, miners do. Miners never stop, and each [some interval] they fetch a new block template from the pool operator's node, wh[ose merkle hash] includes new transactions. When they find a block, it is published and transactions ...
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In addition to Chytrik's mention of a dust attack, dust limit transactions are also used heavily by the Omni Layer to identify the recipient of an omni asset. Transactions such as those will follow pattern of one dust (or near dust) output, an OP_RETURN output, and a change output.
While dust attacks tend to create thousands of dust outputs in a handful of ...
2
This output value corresponds to the dust limit that is imposed on bitcoin transactions.
Many of these outputs may have been generated as a dust attack to de-anonymize users/ addresses.
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I think you have pretty much answered the question yourself. The only use case I can think about for implementing social network on a blockchain is if you are hosting content that is illegal (connecting the likes of drug dealers, child porn makers etc.). In that case you can be assured that since there is no single point of failure, the law enforcement ...
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Blockchain.com API could be an option. I use it for checking incoming transactions and confirmations. It is free.
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LCC-core is not asking for your Trezor passphrase (25-word) which, as you said, you didn't set up. LCC-core is asking for your wallet.dat passphrase which is the passphrase used to encrypt the contents of the LCC-core wallet.dat file. This was a passphrase you set when you originally installed and set up the LCC-core software.
Just a point of advice. You ...
0
All in theory:
Moore's Law will compromise all proof of work algorithms as newer mining equipment becomes affordable to fewer and fewer miners. Eventually one miner will have 51% control and it doesn't need to be quantum.
However quantum would be a definitive answer to your question because Moore's Law is steadily approaching its limit for conventional CPU ...
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