Questions tagged [hash]
A hash is the output of a hash function, a function which is a mathematically reproducible but irreversible process that takes in an arbitrary length input and produces a fixed length output. The same input will always result in the same output. Hashing is central to Bitcoin mining as well as the generation of Bitcoin addresses.
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How often does target hash change and how to find it?
So basically I was researching target hash and trying to figure out how I can find it. I know there are posts out there that have said that Bitcoins target hash is a 256 bit number with 32 bits of ...
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How can i achieve this signature?
I want to make a signature in bitcoin where the nonce and private are the same. For example, the private key is 0x1000 and the nonce for the R value is also 0x1000
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How to calculate the hashes in Lightning
I was wondering how I calculate the hashes regarding BOLT03 Specification:
The Revocation Pubkey is calculated like this:
revocationpubkey = revocation_basepoint * SHA256(revocation_basepoint || ...
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What needs to be changed in Bitcoin if SHA-256 is broken? [duplicate]
I come up with a little bit "catastrophical“ question. I declare that I understand the degree of improbability of such a scenario in our lifetime, but I would still be interested in your opinion. ...
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Mining against candidate block hash or previous block hash? [duplicate]
When mining...;
a) Is the block header hash of the candidate block used
b) OR the block header hash of the previous block + noonce used?
If it is a), which I presume, is it then correct that the ...
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Bitcoin transaction inquiry
if suppose a someone offers a prize for anyone that can solve a specific challenge, how will the solver make sure that he/she collects the reward? Does the solver need to send the solution directly to ...
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Why does my hash not line up with the one in the scriptPubKey?
I got some btc in testnet, here are the outputs.
this is the UTXO that i get my btc
{
"value": 17.24756333,
"n": 1,
"scriptPubKey": {
"asm": "...
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One address 2+ private keys. Bitcoin future
Since bitcoin uses cryptography algorithms to create private and public keys there is a possibility it could repeat.
Person 1:
L54w...KraG -> bc1...kq4
Person 2:
L3mV...JU8G -> bc1...kq4
So ...
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What actual steps are required to calculate a block's header hash?
From my knowledge a header hash will be calculated like this:
serialize all header fields, including "the nonce"
hash the serialized header once
hash the hashed serialized header again
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Calculate/Verify the Hash of a Bitcoin Block Header
I want to calculate/verify the hash for block #722,460.
Here is the JSON:
"hash": "00000000000000000002b73f69e81b8b5e98dff0f2b7632fcb83c050c3b099a1",
"confirmations": ...
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How many times and where exactly is ECDSA used in Bitcoin?
I'm currently a little confused about where exactly ECDSA is used in the transaction process... some resources seem to say it's used once, whereas others seem to say it's used three times.
Which is ...
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Want to verify previous block hash and prove of work
I want to verify several random blocks and check if there was prove of work really found. I need it for some reasearch reasons. I have downloaded the blocks historical info and there are only hashes ...
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Stumped on finding checksum for 12 word Bip39 mnemonic
I read Pseudo code to find Bip39 checksum? and followed the steps outlined by the answer and arrived at the correct checksum.
But when I went to try it on a 128 bit entropy that were all 1s: ...
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How to forge a signature with fixed Z value
I want to forge a signature with a fixed z value, what is the formula to do that
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why do we need to hash before we use a private key to digitally sign a transaction? isn't just using a private key enough?
why is a hash needed for digital signatures? isn't it redundant since the point of hashing is to ensure contents are not tampered with , which the digital signature can do as well (on top of ensuring ...
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