Questions tagged [transaction-verification]
The process in which every Bitcoin node checks every part of every Bitcoin transaction worldwide for conformance to standard rules and uses the complete history of all previous Bitcoin transactions to check that money being spent in a transaction has not previously been spent in any earlier transaction since the beginning of Bitcoin.
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Why is there no such thing as a redirected, forged, or fake transaction?
In the past, we had numerous questions about "fake" or "forged" transactions. Such transactions could supposedly be created even without holding any bitcoins, yet would end up in the mempool or even ...
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Verifying a bitcoin trx on the Unix cmd line with OpenSSL?
I want to use openssl on unixoide systems to verify a transaction. I step on errors, when trying to verify a bitcoin trx’s hash. Here I am working on Mac OSX and OpenSSL (1.0.2a 19 Mar 2015).
I know ...
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What's the blocksize limit after segwit and how do legacy nodes deal with segwit transactions?
Normally, I heard that the bitcoin blocksize is 1MB, but with the Segwit update the blocksize can be up to 4MB, so we should say that the blocksize is 4MB, right? Moreover legacy nodes only receive ...
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How is SegWit a soft fork?
Reading this section of BIP144, I noticed the followng statement:
Parsers supporting this BIP will be able to distinguish between the old serialization format (without the witness) and this one. ...
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Full list of "special cases" during Bitcoin Script execution (p2sh, p2wsh, etc.)?
When executing a Bitcoin Script, there are some "special cases" where the interpreter performs extra verification beyond just executing scriptSig and then scriptPubKey.
For example, if the ...
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What are the advantages of Schnorr vs ECDSA?
I understand that Schnorr signatures provide an improvement on ECDSA in that they are a fixed 64 bytes instead of the longer ECDSA sig format, however, I don't see how this is an advantage over ECDSA ...
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Why is mining necessary for the Bitcoin network/system? [duplicate]
I understand that a transaction is a record of 1+ Bitcoins being given from one party to another.
I understand that a block is a collection of unverified (pending) transactions that gets verified ...
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Incentive for validating block
When miners find a solution to a block and broadcast it, what is the incentive for the other miners to actually validate that it is correct? It seems that they might save time by just starting to work ...
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How can transactions be verified without the private key?
Trying to get my head around her royal Bitcoin here...
I understand that blocks of transactions are broadcast to the network, and that miners verify that the BC is 'spendable' by trawling the ...
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How are bitcoin transactions and the blockchain transferred over the internet?
So I have several specific question connected to this topic and I'm aware of the conceptual answers and I'm only interested in the technical details (with programming terms and concepts as I'm a ...
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How do nodes verify Bitcoin Transactions?
I am trying to understand the role played by various nodes in the Bitcoin Network in verifying the transactions that are taking place in real time. I think that I understand the process of Transaction ...
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How to calculate signature generation, signature verification, transaction verification speed?
I read this post on Bitcoin Scalability.
As far as I understand sequence of steps in Bitcoin, simplified version of performing transaction should be following:
On Sender's side:
Create transaction
...
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Transaction's maximum size
Is there a maximum size for any given transaction?
I just created this tx:
http://blockexplorer.com/testnet/tx/194173dcc07b396433d5725abe76d52b10d42ebd3d1d10b465429f87fee12a52
and although it ...
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Which kinds of transactions show quadratic signature-hashing scaling?
It has been stated:
A major problem with simple approaches to increasing the Bitcoin blocksize is that for certain transactions, signature-hashing scales quadratically rather than linearly.
https:/...
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How confirm my own doublespend transaction got confirmed
Transactions in the testnet are right now almost always double spent with a new txid (possible due to tx malleability). This is actually quite nice for testing purposes.
So I'm wondering - when I ...
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What counts as verification or validation of a transaction?
I understand the general ideas and properties of the block chain, but have not been able to understand how a transaction is created and gets to be verified or validated.
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Does the version prefix of an address force the type of transactions the address may treat?
A Bitcoin address is created with Base58Check encoding and it requires a version prefix, such as 0x00 for a P2PKH(pay-to-public-key-hash) address, 0x05 for a P2SH(pay-to-script-hash) address.
Does ...
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relationship between bitcoin miner and verification of transactions [closed]
Bitcoin miner mines a block, which can't be submitted to the network without proof of work. And the new block contains all of the new transactions. Hence the new block acts as a security measure, and ...
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Is it possible to add a transaction input to a transaction in the mempool?
Is it possible to add an input to a transaction that is in the mempool?
For example, if someone is paying 1 BTC to their friend, I can get the raw hex data of this transaction from the mempool before ...
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Transaction verification by miner VS full node with & without SegWit
I'm trying to fill a few gaps in my understanding of transaction verification and would appreciate any insight.
Without SegWit
Miners broadcast new blocks which contain the signature(s) with every ...
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What happens in detail, when Bitcoin Core verifies a block during synchronization?
Since version 0.10.x, block headers are acquired separately, and therefore download is not delayed until previous blocks have been verified.
Previous questions about synchronization mention that the ...
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How are blocks verified?
I see in the bitcoin wiki there is something called "script" which compiles down to some bytecode to be run by a very very basic virtual machine.
Does this mean that each block is actually just a ...
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Where the P2SH script gets written?
I understand that when I'm doing a transaction, I'm locking those bitcoins to whoever provide the solution to a script that has the hash I posted.
But, where does the hash get written?
I would ...
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Exhaustive technical explanation of signing & verification
I apologize for such a noobish question and am ashamed that I'm not getting this yet, but I can't seem to put together all of the pieces. I've read every question I can find on the subject, the ...
user5107
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How does Proof of Stake prevents dishonest behaviour compared to PoW?
I know that in Proof of Work (PoW) once a node has found the solution (the nonce) they announce it to the network. Then the rest of the nodes can easily verify the correctness of the block hash and ...
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Do full nodes store the complete merkle tree or do they regenerate it when creating a merkle proof?
I understand what the merkle root is for. And I understand that blocks don't store the merkle tree.
Question 1) Is there any place that the complete merkle trees get stored? I don't mean the merkle ...
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How to tell if a transaction is valid?
So I have been reading up on bitcoin and blockchain for awhile now, but I have yet to fully understand it. I understand that bitcoin leverage on DLT, which uses cryptography to verify transaction. ...
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Is there any way to send an output to a script which can then only be sent to one of two addresses?
Is the following scenario possible?
I want to send money to a script. This script will require knowing a private key to spend, as usual, but the script is only valid if the money is being sent to one ...
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Ethereum - how is the output of a contract computation verified? [closed]
This may be as simple as a pointer to some place in the docs I've missed, but how/where is the output of a contract's computation checked, or assured against a malicious miner with an intentionally ...
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How are transactions verified to ensure only the eligible person can spend a Bitcoin balance?
I know each user has a public key and private key. The users signs the transaction with his private key and sends it to a Bitcoin address. What prevents me from claiming his coins? I read something ...
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How Blockchain transaction verification takes place?
How does each transaction verifying node come to know if the sender has enough amount in its wallet to transfer to the receiver or not? How are Blockchain transactions validated?
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How can a miner verify that a UTXOs is not spent elsewhere?
How does a miner verify that a UTXO is not spent somewhere else, wouldn't he have to search the entire blockchain from that UTXO and onwards to see if this was the case? Assuming any real scale this ...
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If two parties submit a conflicting transaction between each other, how does the network decide which one is correct?
Let's say parties A and B both submit a transaction to the blockchain with a different version of what happened. Party A submits a transaction saying Party B gave him 3 BTC and Party B submits a ...
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When creating a transaction, how can you prove that you own your address without exposing your private key?
I'm trying to understand how Bitcoin works under the hood, but there's something I don't get at all, and can't find it.
Suppose I own address A (I have the public key, A-public, and the private key A-...
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Can anyone initiate a Blockchain transaction into the mining pool?
Let's say user A has public key P and corresponding private key P'. Can someone else initiate a transaction for public key P with some wrong private key, let's say P''? Once this goes to the memory ...
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How does a non-upgraded node read a SegWit transaction? [duplicate]
I'm trying to understand how my node would interperet a SegWit transaction if I do not upgrade.
Even if I do not upgrade, I should be ...
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"Instantaneous" transaction verification?
Jan Moritz Lindemann graciously educated me that difficulty is used not only to regulate the creation rate of a cryptocurrency but also to allow for block propagation thus prevent orphaned blocks.
...
user5107
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Verification of transaction once trasaction is broadcasted
I have few doubts regarding verification of transaction and am trying to find answers from last few days. I agree similar post exist in this portal but I am not getting satisfactory answer for my ...
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Why can't someone create a valid digital signature without knowing your private key?
I understand from the following two posts that private keys are not displayed by the sender when getting their transaction validated by the bitcoin miners:
What happens to Private Key on Payment
How ...
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Bitcoin fake transactions
Suppose, A and B are malicious attackers. Both want to send unlimited fake transactions to each other. I know that the transactions won't be accepted in the blockchain. In fact, they don't want their ...
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Exchange Transaction versus Blockchain Verification
I am wondering about a question related to this post. According to bitcoinity, the number of bitcoin-trades at major exchanges per minute is roughly 400. However, as also pointed out by @eponymous in ...
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How are transaction fees claimed from a technical point of view?
A typical transaction has one or more inputs and one or more outputs. Since there is no amount specified for inputs, the rule is that ALL of the inputs is always transferred. Any discrepancy between ...
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how does bitcoin solve the same chain replay attack?
Let's say I send 10BTC to Bob. I have 30 BTC. So after transferring, I should have 20.
Now, after I transfered 10, transaction can be copied and broadcasted to the network again by Bob(he might have ...
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Is a miner running a full node?
Is a miner just running a full node that is connected with the mining hardware? Or is there such thing as a miner node? Does it use additional software for transaction selection?
Thanks in advance!
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Why does only the earliest transaction matter for double spending?
On page 2 of Bitcoin paper, it says:
The problem of course is the payee can't verify that one of the owners
did not double-spend the coin. A common solution is to introduce a
trusted central ...
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Bitcoin transactions validation process
I have a general understanding of building blocks. But am hoping someone can fill in the details/gaps. Also, can you correct if something is not right? Thanks.
Scenario:
Bitcoin transactions are ...
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P2SH secure spending. How?
Maybe my question is stupid, but
imagine that I'm trying to spend inputs from p2sh.
For example, p2sh scriptPubKey looks like:
OP_SHA256 ...
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Does the miner first validate transaction before doing POW or he does not validate at all ? [duplicate]
Does the miner validate the transaction before putting it on the block for proof of work?
my understanding is if the miner does not validate the transaction and published the block and the block gets ...
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Sent BTC from Coinbase, blockchain explorer says Confirmed. Is recipient lying or could something else be the issue? [duplicate]
Sent BTC (approx $500) from Coinbase, Blockchain explorer says Confirmed. Is recipient lying they have not received or could something else be the issue such as his wallet?
Recipient says it could be ...
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Verify Bitcoin Transaction
Following the great post [Redeeming a raw transaction step by step example required, I came up with code below but the verification failed.
// pubkeyBytes, len: 65
// ...
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