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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If SHA256 is successfully attacked, will we need to replace the hash function and re-timestamp the entire blockchain from the beginning?
If SHA256 is successfully attacked, what measures will be taken to replace the compromised hash function?
In the event of a SHA256 attack, will it be necessary to re-timestamp the entire blockchain ...
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Is PoW an indispensable component in blockchain?
There is an argument that if the Proof-of-Work (PoW) mechanism is removed from the Bitcoin network or if the puzzle does not have a sufficient level of difficulty proportional to the computing power ...
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In what order is the blockheader hashed?
In what order are the hash of the previous block, the root of the merkle and the nonce hashed to produce the hash of the next bitcoin block?
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How can a collision attack reveal the private key?
From "Mastering Bitcoin: Programming the Open Blockchain 3d edition, Ch4" :
All addresses based on hash functions are theoretically vulnerable to an attacker independently finding the same ...
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Computing HASH160 of a Taproot X-only 32 byte Public Key
I know that Taproot does not use pubkey hashes, but I want to compute a HASH160 of a 32 byte Taproot X-only public key anyway. The rationale is to compare it to an existing 20 byte HASH160 from a ...
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What is the advantage of using truncated HASH256 over CRC32?
Some of the checksums in Bitcoin are the first 4 bytes of the HASH256 of the data. HASH256 is just double SHA256, so SHA256(SHA256(data)). What is the advantage of that over using a dedicated checksum ...
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What is one word seed word exactly?
I have the following code
import hashlib
import binascii
def word_to_private_key(word):
sha256_hash = hashlib.sha256(word.encode()).digest()
private_key = binascii.hexlify(sha256_hash).decode(...
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Verify Hash from bitaddress.org without the original HTML file
Can I verify that I used an authentic version of bitaddress.org if I only have the SHA256 hash string I generated from the HTML file?
>> sha1sum bitaddress.org.html
How can I do this on Linux? ...
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Problem identifying the transaction hash for a new segwit uxto wallet
How do I the transaction id or transaction hash of a new segwit wallet I just created and sent tokens to? The transaction hash I see from blochian.info refers to the hash of the previous transaction.
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What is the numeric precision of Network Difficulty?
My understanding is that Difficulty (aka Network Difficulty) is an approximate representation of the Target, a 256-bit number which is hard to reason about or work with in human-readable Decimal ...
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What is TXID？Is it used to calculate merkleroot [duplicate]
I downloaded the block template where each transaction contains 'data', 'txid', 'hash'. I read in some articles that the Merkelroot is calculated using 'txid'. Is true? Why txid not hash, and what's ...
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How to calculate Merkle Root? Need to reverse?
I downloaded the necessary information and made the coinbase. Then I calculated the merkle root... But I always get an error message when I submit a block: "bad-txnmerkleroot". Tere is my ...
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What are hash functions used for in bitcoin?
What are hash functions used for in bitcoin?
I am looking for a comprehensive list.
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Address Reuse and ECDSA Concern
I have a question about address reuse. Admittedly, I'm a little confused on the matter, so please bear with me if the framing of my question doesn't make much sense.
Recently I started using Sparrow ...
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How to hash a message (tx message) to get message hash? [duplicate]
I am trying to create a raw TX and sign it. I know that to sign a transaction we need the message hash (here m) value which is double sha256 hash of something like this:
01000000 #Version
01 #Number ...
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