Questions tagged [sha256]
A 256-bit variant of Secure Hash Algorithm 2
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Why CPUMiner does not mine in spite of showing good hash rate? [closed]
I tried cpuminer to mine some nominal crypto. But, even after 12+hours , not even one share has been obtained. What is the problem in my command. Like, I used the command
./cpuminer -a scrypt -o ...
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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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Schnorr batch verify random number generation method
Is there a specific way that you must generate the random numbers for batch verification with Schnorr signatures?
In BIP 340 it describes this method for generating each random number:
seed = SHA256(...
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Bitcoin Core VM and hardware SHA256
It has come to my attention recently that linux machines store info about their cryptographic capabilities in /proc/crypto.
A baremetal machine I have shows sha256_ssse3 in the sha256 module parameter,...
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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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Is it always possible to find a number whose hash starts with a certain number of zeros?
As I understand it, proof of work requires nodes to "scanning for a value that when hashed, such as with SHA-256, the hash begins with a number of zero bits" ([bitcoin paper])1.
Specifically,...
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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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Does the hashrate/hash power represent the number of single or double sha256 operations that can be done per second? [duplicate]
When we state that someone has, for example, a hashrate of 240 H/s, does it imply the capability to perform 240 SHA256 hash operations (equivalent to 120 double-SHA256 operations) or 240 double-SHA256 ...
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SHA-256 hashing algorithm
Where in the Bitcoin github repo is the SHA-256 hashing algorithm defined? Is it a methematical formula?
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calc Block Header hash
I use the following code to calculate the header hash.
function serializeBlockHeader(blockHeader) {
const version = Buffer.alloc(4);
version.writeUInt32LE(blockHeader.version);
console.log(...
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Verifiable way to share knowledge of bitcoin address
I am looking for a simple or standard way (government bureaucrat-proof) to share knowledge of a bitcoin address in a legal contract without revealing the address itself. Having to reveal the address ...
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How can I hash a block header using bitcoin-cli and terminal commands?
I would like to hash a block header using terminal commands and look at all the pretty leading 0s, but I can't figure out how to do this correctly using block header data from bitcoin-cli.
Here is ...
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Are miners advertised hash rate single or double hash speeds?
Modern miners on the market have up to 110 TH/s. Is this the true hash rate (singular SHA-256 hashes per second) or the net hashes relating to Bitcoin specifically (since Bitcoin involves double ...
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replicating Hash160 with SHA256/RIPEMD160
I have a dumb question about Hash160 (specifically, going from a public key to Hash160).
If I take a public key: ...
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How long would it take for all smartphones on the planet to fully reverse a SHA-256 hash?
I am aware that, theoretically speaking, there is no way to guarantee that a reversed hash is actually what is inputted to the hashing function. However, let's say that I have an image, I write down ...
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