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.

Filter by
Sorted by
Tagged with
2 votes
1 answer
1k views

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-...
nohamk's user avatar
  • 123
2 votes
1 answer
82 views

Which sender is banned in case of invalid transactions or blocks?

When a node receives an invalid transaction or block, as far as I know, it bans the sender for 24 hours. However, I didn't exactly get which sender is banned. Is it the neighbor node that provides the ...
Önder Gürcan's user avatar
2 votes
1 answer
535 views

why verification of transaction after proof of work?

I have question about bitcoin protocol. In Satoshi's paper it is mentioned that: New transactions are broadcast to all nodes. Each node collects new transactions into a block. Each node works on ...
Mary_Si's user avatar
  • 21
2 votes
2 answers
1k views

Does an Invalid Transaction persist in the mempool?

My basic understanding is that a transaction will continue to exist in the MemPool until it can be completed, (or eventually gets evicted due to the size of the MemPool). To me, this leads to a ...
abelenky's user avatar
  • 1,344
0 votes
1 answer
220 views

What happen to my bitcoin

I have payed last april 21 and april 25 should be my payment but it took days already here is my transaction id b5a9cb6a67429ec60c51f3aa197bec67af0003c841890132051f9fea40f71f76 And the same as april ...
Mark's user avatar
  • 1
2 votes
1 answer
431 views

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 ...
inersha's user avatar
  • 2,968
0 votes
1 answer
93 views

tx-malleability who re-signed the tx?

It would be really great if there was a way to loop through all the txids in a new block and be able to check if you (can) sign your original transaction the same way it was re-signed - that it ...
Ben Muircroft's user avatar
2 votes
2 answers
259 views

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 ...
tobi's user avatar
  • 135
2 votes
1 answer
1k views

How does merkle tree verification of transaction work?

From what I have read, suppose B sends 1 bitcoin to C. C wishes to verify B's payment and asks C for the block number (location) that input transaction is located at. (Is this correct understanding/...
Geo Mez's user avatar
  • 61
3 votes
2 answers
2k views

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 ...
no nein's user avatar
  • 297
21 votes
1 answer
2k views

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. ...
Simone Bronzini's user avatar
0 votes
1 answer
199 views

How can I work out why a transaction isn't being included in any blocks? [duplicate]

I've crafted a testnet p2sh address using python-bitcoinlib. The script contents is 2-of-2 multisig: 2, key1, key2, 2, OP_CHECKMULTISIG Redeem script: ...
Acorn's user avatar
  • 101
2 votes
1 answer
253 views

Double spend a tx output already spent but unconfirmed because of low fee

In the protocol rules for validating transactions it says: Rule 9: For each input, if the referenced output exists in any other tx in the pool, reject this transaction.[5] I assume that when a ...
miguel's user avatar
  • 135
1 vote
1 answer
655 views

Bitcoin testnet3: unable to push/publish raw transaction: how to verify validity of transaction?

I have created a raw transaction and am now trying to push the hex format into testnet3. I have used following two ways and both are giving me two different errors, first one: curl -d '{"hex":"...
Tuhina Singh's user avatar
1 vote
2 answers
389 views

Who pays for the computational cost when validating a transaction

Suppose Alice wants to validate a transaction (check this transaction does exist, not make a new transaction), and suppose her has not downloaded all transaction history. My understanding is, 1) ...
zhanxw's user avatar
  • 113
0 votes
3 answers
3k views

How does the Bitcoin Network verify whether the wallet has enough bitcoins for the transaction?

How does the Bitcoin Network verify whether the wallet has enough bitcoins for the transaction? I understand that it is verifiable by scanning the entire blockchain and see whether the wallet has the ...
Jaebum's user avatar
  • 103
3 votes
3 answers
822 views

How can I find the coinbase transactions where the bitcoins involved in a transaction were created?

I am exploring a transaction and if would like to know when was the money created, I guess I would end up with a lot of coinable transactions. For a certain transaction I could explore the previous ...
muimota's user avatar
  • 192
8 votes
2 answers
5k views

Different error messages under "Mandatory script verify flag failed."

I've been playing with raw transactions and signed transaction and I've noticed that the error "Mandatory script verify flag failed" comes in two variations. script failed on OP_EQUALVERIFY OP Script ...
shultz's user avatar
  • 181
2 votes
1 answer
105 views

How are past transactions validated (when there have been softforks)?

Let's say I run a bitcoin client for the first time. It downloads a copy of the blockchain from the very beginning and starts validating all the transactions included in all the blocks. Since there ...
cpsola's user avatar
  • 1,598
2 votes
3 answers
1k views

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.
Roberto Gejman's user avatar
3 votes
1 answer
622 views

Signing tx with OpenSSL, but fails when sending with bitcoin qt. How to debug?

I try to create a tx with 4 inputs, and sign it via cmdline and openssl on a cold storage machine. Then I want to send it via bitcoin qt (or blockchain.info). Signing with a single input and a single ...
pebwindkraft's user avatar
  • 5,086
0 votes
1 answer
94 views

separating proof of work from mining possible?

I (think to) understand that proof-of-work is the process through which transactions are verified and the health of the network is being ensured. I also (think to) understand miners get bitcoins for ...
transient_loop's user avatar
2 votes
1 answer
73 views

What information about a transaction can be assumed accurate before confirmation?

When sending a Bitcoin transaction, what information in that transaction can be assumed to be accurate before receiving a confirmation? Can you verify the from address? Can you verify that the ...
user1929274's user avatar
1 vote
1 answer
192 views

Why will a miner verify the digital signature, instead of directly adding a transaction to the Merkle tree?

I am a complete noob to Bitcoin, and this question might seem obvious to some. But I can't seem to get my head around it. I read how the process of mining works - they select transactions, verify them,...
sad_943's user avatar
  • 13
0 votes
1 answer
208 views

Verify value of input address

Think about a bitcoin transaction: Inputs: Address1: 2 BTC, Address2: 1 BTC Output: Address3: 3 BTC So the value of Address1 is because of two previous transactions where every one of those 2 ...
Erhard Dinhobl's user avatar
1 vote
3 answers
133 views

How do Bitcoin and Colored Coin react to malformed transactions?

I need some help to clarify Bitcoin and colored coin mechanics. Are the assumptions below correct (and complete)? If an error (maybe a fraud) is presented in a Bitcoin transaction, nodes (including ...
Ricardo Zylbergeld's user avatar
0 votes
1 answer
170 views

Does a new nodes verify all transactions or only blocks

When a node downloads the genesis and all blocks, does it verify all past transactions, or just the blocks (eg check the nonce/hash relation, thereby assuming the containing transactions must be right?...
BlockChange's user avatar
3 votes
1 answer
2k views

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 ...
pebwindkraft's user avatar
  • 5,086
1 vote
2 answers
233 views

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 ...
Harry Pillsbury's user avatar
4 votes
3 answers
709 views

How do miners understand what a transaction does?

Bitcoins are spent via transaction scripts that can be quite complicated. How do miners understand what a transaction does? A miner has to decide whether to include a transaction in their block, but ...
Harry Pillsbury's user avatar
1 vote
1 answer
83 views

Will Bitcoin remember unperformed transactions?

Let's say I transfer 0.05 BTC from 1 input to 1 output and don't pay a fee. If there are 6 blocks per hour, this means that my input has to be 369 hours (about 15 days) old so no fee is required. Let'...
UTF-8's user avatar
  • 3,224
2 votes
2 answers
458 views

Confirm own incoming transactions

Is it possible to only mine your own incoming transactions? So you can confirm a Bitcoin transaction (only locally).
Daniel Gelling's user avatar
0 votes
1 answer
618 views

What is the memory usage for checking transaction inputs?

Whenever a transaction is received by a node, the node verifies its validity. To that end, it checks for each transaction input whether that input is part of the UTXO set. It is my understanding that ...
Murch's user avatar
  • 72.6k
1 vote
0 answers
195 views

Do Bitcoin miners verify validity of merge-mined Namecoin blocks?

I've been reading a little about merged mining as used in Bitcoin and Namecoin. It seems like merged mining effectively eliminated Namecoin-only mining pools, right? Since Namecoin-only pools are ...
Alin Tomescu's user avatar
  • 1,337
0 votes
2 answers
624 views

How is it possibile to verify payments without running a full network node?

I've read the Nakamoto's paper "Bitcoin: a peer-to-peer electronic cash system". In paragraph Simplified Payment Verification he said that is possible to verify payments without running a full network ...
alessandro308's user avatar
5 votes
1 answer
1k views

What is an "insecure transaction type", as mentioned by Bitcoin Wallet for Android?

I am running Bitcoin Core v0.11.0.0-gd26f951 (64-bit) at home on Ubuntu, and have installed the Bitcoin Wallet for Android on my phone. I sent two transactions from home to my phone: First, Second. ...
Pepijn Schmitz's user avatar
5 votes
1 answer
493 views

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 ...
araqueto's user avatar
2 votes
3 answers
558 views

Why do nodes trust other nodes to approve their transactions?

I know that the blockchain technology works so well, because everybody has basically a copy of the last ledger. Therefore, if a transaction happens, everybody inside the network has to "approve&...
Carol.Kar's user avatar
  • 141
5 votes
1 answer
359 views

Why do bigger blocks make it more expensive to run a full node?

Does it cost more storage? For the transaction verification, to which extent bigger blocks make it more computational intensive? In terms of computational complexity, is the verification process a O(n)...
czheo's user avatar
  • 151
6 votes
1 answer
256 views

Does every full node verify every transaction TWO separate times?

I am building my Bitcoin expertise, and want to verify my understanding on a specific point: at what point(s) do all full nodes verifies a new transaction? Here is my understanding in a nutshell, ...
Pressed250's user avatar
2 votes
2 answers
333 views

I Want To Confirm That My Bitcoins Are Being Held In New Wallet

I sent a couple bitcoin from one of my trezor wallets to a different trezor wallet. I don't know the details about how bitcoin "sending" between wallets work, and now I feel the need to confirm that ...
Aiden Feron's user avatar
4 votes
1 answer
577 views

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 ...
Nur's user avatar
  • 431
6 votes
1 answer
228 views

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 ...
Murch's user avatar
  • 72.6k
3 votes
1 answer
818 views

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 ...
JesseM's user avatar
  • 131
1 vote
1 answer
1k views

OP_CHECKSIG signature hash type 0

On the Bitcoin Wiki's OP_CHECKSIG documentation: Firstly always this (the default) procedure is applied: the public key and the signature are popped from the stack, in that order. If the ...
bitaps.com's user avatar
0 votes
0 answers
107 views

How to send an invalid transaction for testing purposes?

How could I send an invalid transaction—for testing purposes, such as with testnet or regtest? For example, I would like to to try to double-spend, spend non existent coins, etc.
Geremia's user avatar
  • 4,556
1 vote
2 answers
346 views

How instantaneous is a Bitcoin transaction?

How quick does a bitcoin transaction happen? (assuming that both parties are online at the time) I read somewhere on the Internet that it's not recommended to accept a bitcoin payment right away (...
Taher Elhouderi's user avatar
7 votes
1 answer
312 views

Is the SPV client model scalable?

SPV clients typically connect to full node peers and set filters on what information they download. How many SPV peers can a single full node support, typically? Is it reasonable to expect millions ...
morsecoder's user avatar
2 votes
2 answers
347 views

Does value 'True' at the middle of stack is valid transaction?

If at the middle of the execution of scriptSig + scriptPubKey we get the value 'True', while there are remaining values or operators in the stack, is the transaction valid? Or should the stack be ...
Haddar Macdasi's user avatar
0 votes
1 answer
102 views

What is A matching transaction in the pool validation?

I'm reading "mastering bitcoin" and got into transaction validation. Can you explain to me what is the meaning of "A matching transaction in the pool, or in a block in the main branch, must exist." ?
Haddar Macdasi's user avatar