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1answer
14 views

verifying my modifications to bitcoind w/o broadcasting anything

I want to verify that my updates to the bitcoind source code don't break anything. One way that I thought of doing that was through loading the mainnet data into a regtest instance. To do that I first ...
0
votes
3answers
39 views

Reject or refuse to relay a valid transaction

Under the Bitcoin protocol, how much control does a node have on how a transaction is dealt with once received? Can a node reject a valid transaction? Can a node refuse to relay a valid transaction to ...
0
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1answer
30 views

Who set the rules for validating a block in blockchain?

Who set the rules for validating a block in blockchain? The rules can be set the creator of the blockchain network. There might be some rules on the application that uses the blockchain network. Is ...
1
vote
1answer
38 views

What is the correct use of the term “validating”?

First, in the Bitcoin context what does validating mean? Second, is it incorrect to say something like " the average time it takes to validate a block by the network is 10 minutes." The way, I ...
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2answers
27 views

How nodes verify if the hash on a P2SH output is from a valid script?

I understand how the validation works if someone wants to spend coins from a multisig address. But what if the receiver makes a mistake and provides an invalid script hash to the sender? Is there ...
0
votes
1answer
29 views

When are blocks validated?

Are blocks validated just before they are stored to memory, upon receipt from an RPC submit call, or at some other time? Can you point to the place in code where this validation process begins? Is ...
0
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1answer
40 views

Link to Algorithmic behind signatures verification [duplicate]

Does anyone know a good paper where the process of signature verification is explained (message+signature+public key = valid/not_valid) ??? And I mean it at a low level, with the code or pseudo-code ...
0
votes
1answer
39 views

How does the p2p network monitor the validity of a transaction?

In Bitcoin, in order for a transaction to be added to the pool of valid transactions that will be added to the chain block by the miners, at least 51% of the nodes/peers need to review that ...
1
vote
1answer
28 views

Is it possible to append new blocks to a block of arbitrary age?

First of all, I'm aware of 51% attacks and how they work. Though, I was wondering, if Bitcoin and other blockchains allow appending cryptographically valid, new blocks to blocks of arbitrary age (if ...
0
votes
2answers
68 views

What’s the difference between a validation by nodes and a verification by miners?

In Mastering Bitcoin, it says: The transaction is then broadcasted on the bitcoin network, where each network node (participant) validates and propagates the transaction until it reaches (...
0
votes
1answer
25 views

Validation methods beside POW etc

Are there other concepts for the validation of the next added block to the blockchain beside POW, POS etc.? Of cource there are, but is there a methode that is shining out of the mass? A methode that ...
0
votes
1answer
58 views

Can you create a valid p2sh transaction with the redeem script in the scriptsig alone?

From my understanding, for a p2sh transaction to be valid the redeem script must hash to the same value as the output script being used to fund the transaction. So can't you just put the redeem ...
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0answers
23 views

How is transaction validated ( edited for unanswered question)? [duplicate]

What are exactly checked during this validation process? All transaction histories associated to the coins used in this transactions? And then who decides which block a validated transaction goes to? ...
1
vote
1answer
50 views

What prevents anyone from spending utxos from a native segwit address?

I read that transactions spending utxos from a native segwit address ( an address starting with bc1) are seen as anyone can spend transactions by legacy nodes. So what prevents someone from taking a ...
0
votes
1answer
36 views

Do miners check whether a transaction is segwit or non segwit?

When a transaction is pushed directly to a miner does it check whether the transaction is segwit or not or only if it is valid?
0
votes
1answer
87 views

How can i create an Anyone can spend output?

How can i create an Anyone can spend transaction using p2pkh outputs? Also how would such a transaction in hex look like?
0
votes
1answer
39 views

Can op codes be used instead of signatures?

Are there any op codes or combination of opcodes that can be used instead of a digital signature when creating a transaction?
0
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0answers
20 views

Valid p2sh transaction using only the redeem script

Is it possible to create a valid p2sh transaction using only the redeem script in the scriptsig and no signature?
1
vote
2answers
44 views

Does a node validates a transaction that comes with a block if it's already in its mempool?

Except for checking for double spends, if there's a transaction in a block that's already in the node's mempool, it can theoretically skip its validation. Does it actually happen, or the nodes ...
0
votes
1answer
39 views

Verifying ownership of utxos [closed]

Is there any other way besides signing a transaction to verify ownership of utxos?
0
votes
1answer
38 views

Why does bitcoin use signatures to verify transactions?

Why does bitcoin use signatures to verify transactions in order for them to be broadcasted and mined and is there any other method that could be used instead of signatures?
0
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2answers
23 views

Create a transaction which sends bitcoin to the address it's being sent from?

Let's say address X has 1 btc. Can you create a transaction which would send the 1 btc from X back to X and broadcast it without having to sign it, since the 1 btc is going back into the address it is ...
1
vote
1answer
178 views

How to create a p2sh transaction with a scriptsig of OP_true?

How can I create a p2sh transaction with a scriptsig containing OP_TRUE only, removing the need for a digital signature, which will be broadcasted and mined? Also could some one provide an example of ...
0
votes
1answer
132 views

How to create a valid unsigned transaction

How can I create a valid unsigned transaction which can be broadcasted and mined using these addresses? Could someone create the raw transaction and show me? sender's address: ...
0
votes
1answer
22 views

How can you send a transaction directly to the memory pool?

Is it possible to send a transaction to the bitcoin memory pool directly to have it mined without validating it?
0
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3answers
69 views

Is every bitcoin transaction (eventualy) validated by every miner? [duplicate]

I can see that my bitcoin transfers becomes real when my exchange detects 2 or more confirmations. I believe each confirmation is a validation. Am I correct? If so, How many confirmations will have ...
0
votes
1answer
36 views

How do offchain transactions get validated/confirmed whilst using Lightning network?

How do offchain transactions get validated whilst using Lightning network?
0
votes
0answers
27 views

Is there such a coin?

I am working on an idea that I think could benefit from blockchain technology and a crypto coin. I am looking for help to figure out if something that meets my requirements, which I describe below, ...
2
votes
0answers
170 views

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 ...
0
votes
2answers
44 views

Cryptocurrency exchange needs more info than any bank or brokerage firm?

I wanted to quickly sign up for a cryptocurrency exchange today to act on some info I found out about a low-cost coin (hahahah, quickly. how naïve). In signing up for the account, I got to a step ...
0
votes
1answer
78 views

Block #338819 deemed invalid by v0.15.1

I am attempting to sync from scratch a full node (v0.15.1) on a linux machine (Linux Mint running Ubuntu precise 12.04.1 LTS). The sync grinds to a halt on block #338818. From examining debug.log I ...
0
votes
1answer
38 views

How are transactions verified by nodes other than the initial receiver?

If I understand correctly, when I create a new transaction from my wallet, I have to sign it and encrypt it. My wallet encrypts the message using the public key of the node it is connected to, so it ...
0
votes
1answer
31 views

In a chain split scenario (not soft fork), a miner has to confirm transactions from both chains?

In a scenario where a chain split occurs (two miners find a hash), would miners have to work with both chains until one of then become larger (more PoW)? i.e. Would they have to validate transactions ...
1
vote
1answer
101 views

How can one verify the address you are sending BTC to

I've had an incident with an exchange that provides addresses to deposit BTC funds. For some unknown reason, the exchange is telling me they have never received the funds. I read the address with a QR ...
1
vote
1answer
105 views

Script to periodically update assumevalid block in bitcoin core configuration, good idea?

On my server my full node Bitcoin Core 0.15.1 can take several minutes, on starting, to "validate blocks". And during that time it's thrashing the disk, slowing down everything else. So I discovered ...
0
votes
1answer
201 views

Why is it hard to fake proof of work?

Does someone understand this? "Because of all this work, when a Bitcoin client signs on to the network it can trust the block chain that was most difficult to produce (since this is evidently the ...
0
votes
0answers
13 views

Why would it take over 24 hours to send BTC from Xapo to another wallet [duplicate]

I purchased BTC on Xapo and have sent the BTC to my wallet it has been over 24 hours and the status is still pending/validating. I have done this before and it reflected almost instantly on the ...
0
votes
2answers
146 views

validation of a block with false transactions

When a miner can find a number to create a hash with enough zeros, the other miners can verify his work by testing that number and seeing if everything is correct. But how do they verify that the ...
4
votes
2answers
601 views

Sender, nodes or miners? Who validates transactions?

I have been reading a lot about the validation of transactions. I understand the actual method in which a transaction is composed (inputs and outputs). However, I don't know what happens with that ...
0
votes
1answer
138 views

Difficulty to Hash Validation Correlation

In the validation of a block it is said that a miner has a valid block if the transactions can be tracked in the chain and the hash of the block header is less than the difficulty. I am having a hard ...
0
votes
3answers
270 views

Validation of New Blocks [duplicate]

Basic mining question: Once a miner solves the block and comes up with the block hash, how are the other nodes in the network incentivized to validate that hash?
1
vote
2answers
168 views

What would a full node do if it finds an error?

Full Nodes are supposed to validate every transaction and block in the blockchain, and provide valuable links for distributing blocks. And because the consensus algorithm is extremely good, there are ...
1
vote
2answers
538 views

Blockchain and Transaction Validation

How do the miners check that I have enough Bitcoins. I cannot believe that they will walk through the huge and always growing blockchain established from 2009 to check each Transaction I made to ...
0
votes
1answer
67 views

Block validation files?

Which part of the code is responsible for validating blocks? I'm working on a BIP to modify the structure of block.h, and I think that would definitely affect the validation process. Can anyone point ...
0
votes
0answers
56 views

Validate a NXT / Ardor Address using javascript or js library?

Is there a function or way to validate a nxt address using javascript? A js library would work aswell.
4
votes
4answers
4k views

how to evaluate if this (or any) bitcoin public key / private key combination is valid?

Let's say some software gave me the following combination: public key: 13YcHBzsBX8SxHoBftb69cXJkdXLfAVQos private key: KwfNqMip1ZdgG2o6wYQUBXv8BqkMQ8VWWeScVU5TLPZp31M5EHeq And let's say that for ...
1
vote
1answer
86 views

Possibility of contructing a valid transaction without knowning private key

From here you get that in step 2 of ECDSA sign process, you use z, the Ln leftmost bits of e = HASH(message/transaction) in both the process of generating and verifing the signature. I understand ...
0
votes
1answer
670 views

How to make sure, Bitcoin private key and bitcoin address generator tools are generating valid key pair?

I find lots of tools/scripts written in python which can generate random number then using this random number it generates Bitcoin Private key(WIF) -> Bitcoin Address pair. I have tried verifying ...
3
votes
1answer
253 views

What if the miners allowed invalid transactions, and other nodes did validation?

Here Peter Todd writes: [A]s an optimization Bitcoin goes a step further and disallows invalid transactions to be published in the blockchain at all, but that's the thing: that's just an ...