Skip to main content
20 votes
Accepted

What is "buying hash rate" and how could it be profitable?

"Buying hash rate" is a synonym for a concept called cloud mining. In proof of work-based consensus systems, mining refers to a process of expending computational power to secure the network....
Murch's user avatar
  • 76k
12 votes

Where to find exact number of hashes required to mine most recent block?

You cannot know how many hashes were actually performed for every block, because non-winning hashes aren't published. There is however a simple formula to compute the expected number of hashes a block ...
Pieter Wuille's user avatar
8 votes

How does merged mining work?

Satoshi himself seems to be the inventor of merged mining. In his words (bitcointalk.org): I think it would be possible for BitDNS to be a completely separate network and separate block chain, yet ...
nickler's user avatar
  • 776
7 votes
Accepted

What precisely does the commonly reported network hash rate refer to?

The number reported is an estimation of the number of block headers iterated through by all miners on the network. This means it refers to double-SHA256 hashes performed, not broken down to ...
Pieter Wuille's user avatar
6 votes

What is "buying hash rate" and how could it be profitable?

Although the particulars involve bitcoin, the central issue in this question is more of a Money SE question. You're being asked to invest in [industry], you just have to put up the capital, and [...
Acccumulation's user avatar
5 votes
Accepted

What are the possible Doomsday scenarios for the 2016 Halving from 25 to 12.5 BTC per block solved?

I think you might be referring to the hypothesis that a large portion of the mining power would switch off right at the halving. This is theorized to kick off a chain reaction: Lower network hash ...
Murch's user avatar
  • 76k
5 votes

Why doesn't the same miner always win?

Every miner is working a on different block. While they share some of the same data, there are several parts of a block which are completely up to the miner to decide, and those differences make the ...
Ava Chow's user avatar
  • 70.9k
5 votes
Accepted

How miners with less power win?

That said, when the next block is being mined, again the same person will win because of his computing power. No. Higher mining power means just higher chances to mine a block. If there are 3 miners:...
hardfork's user avatar
  • 2,117
5 votes
Accepted

How do we know which miner or pool mined a block?

We know which miner/pool mined a block only if that miner/pool chose to identify themselves. Most commonly, they do this by inserting their name or other recognizable signature in the block's ...
Nate Eldredge's user avatar
5 votes

Why has BCH not received a 51% attack yet?

Because of the cost, specifically the opportunity cost. If a miner has 10% of the BTC hashrate, then if they pointed all of that mining power to BCH, they would still be losing money. With 50% of the ...
Ava Chow's user avatar
  • 70.9k
5 votes
Accepted

Are there still miners or mining pool which refuse to implement SegWit?

No, in the past year, there were only 15 non-empty-non-segwit blocks mined which account for less than 0.03% of all blocks. Non-empty blocks without segwit transactions I've looked up the last ...
Murch's user avatar
  • 76k
5 votes
Accepted

Is the 'real barrier' to attack bitcoin's consensus 33.34%, rather than 51%?

In this proposed attack, you need more than just hash power. However, if you assume that you can partition the network as this attack imagines, you need no hashing power at all. If I can split the ...
David Schwartz's user avatar
4 votes
Accepted

The probability that the entire network generates at least two blocks within 10 minutes?

Since current hashrate and current difficulty level should be matched up usually, we can disregard them. (Although, we could easily accommodate them if they are diverging as well.) Finding blocks is ...
Murch's user avatar
  • 76k
4 votes

Why the nonce is difficult to find in Bitcoin?

Miners try many block candidates per second. Every candidate is different in some way, but the nonce is only one of the ways in which they differ. Other ways include the timestamp, and - most ...
Pieter Wuille's user avatar
4 votes

How is the hashrate calculated?

As RedGrittyBrick already wrote, the difficulty to create new blocks is adjusted every 2016 blocks. The difficulty provides an expected amount of hashes performed to find a block, which allows a ...
Murch's user avatar
  • 76k
3 votes

What is "If ghash.io hits 51% people would just leave them?" referring to?

GHash.io was a big mining pool back when mining pools were mostly just a way to organize for large numbers of small private mining operations. (Whereas today, the biggest mining pools own huge mining ...
Murch's user avatar
  • 76k
3 votes

What is "If ghash.io hits 51% people would just leave them?" referring to?

No, the network wouldn't disconnect them. There's no way for that to happen. Recall that a pool is an association of miners who agree to share the proceeds of their mining; whenever anyone mines a ...
Nate Eldredge's user avatar
3 votes
Accepted

Hypothetical Scenario - How long does a network correction take?

Details about difficulty adjustment can be found at https://en.bitcoin.it/wiki/Difficulty and https://en.bitcoin.it/wiki/Target. Difficulty adjusts every 2016 blocks, with the goal of keeping the ...
Nate Eldredge's user avatar
3 votes

Will Bitcoin scaling affect the amount of hashing power required to keep the network secure?

This is a comment from page 199 of Mastering Bitcoin. I think its meaning is to be interpreted taking into account the two preceding sentences: Note that the target difficulty is independent of ...
KonKan's user avatar
  • 193
3 votes

How harder is it on average to find a block with one more zero in its hash?

From Applied Cryptography, by Bruce Schneider (pp. 157-158): One of the consequences of the second law of thermodynamics is that a certain amount of energy is necessary to represent information. To ...
maservant's user avatar
  • 1,041
3 votes
Accepted

How does Bitcoin Gigahashes Convert to Ethereum Megahashes?

Bitcoin and Ethereum use different hashing algorithms. General consumer hardware (like a CPU or GPU) can be easily programmed at a software level to perform either the Bitcoin or the Ethereum (amongst ...
Maxwell Sanchez's user avatar
3 votes

Is it possible to know the total hashpower backing a currency?

There are really two different measurements you have to be concerned with for a particular blockchain: The current difficulty (how much hashing power is currently going into single blocks) The total ...
Jestin's user avatar
  • 8,812
3 votes
Accepted

Is it possible to know the total hashpower backing a currency?

Yes. Generally cryptocurrency network mining difficulty is dynamically adjusted by the current available hashing power. Thus, the hashing power must be known. This information is usually disseminated ...
Mikko Ohtamaa's user avatar
3 votes
Accepted

Merchant tool that will dynamically adjust the # of required confirmations based on network hashrate data

Pools can lie about their hashrate, and not claim to have solved blocks that were actually solved by them when. I would propose that this is the wrong method of dynamically choosing a confirm count. ...
fluffyponyza's user avatar
3 votes
Accepted

How many Hashes are in a single Terrahash

Tera is an SI prefix that means 1 trillion. That means 1 terahash/s means 1,000,000,000,000 hashes per second.
Pieter Wuille's user avatar
3 votes

Hypothetical Scenario - How long does a network correction take?

TL;DR: 20 weeks of 100 minute blocks and 5 weeks of 25 minute blocks. Difficulty resets occur every 2016 blocks. In the worst case, the mining power drop would happen immediately after the difficulty ...
Murch's user avatar
  • 76k
3 votes

Hypothetical Scenario - How long does a network correction take?

Short answer: Around six months. Long answer: Assume the drop is instant and occurs right after a retarget interval (block number divisible by 2016). Before we reach the next retarget block, what ...
maservant's user avatar
  • 1,041
3 votes
Accepted

How can someone mine bitcoins at billions or trillions of hashes per second when the nonce is only 2^32 in size?

The timestamp in blocks does not need to be set to the actual time of the current hash. So during mining, the timestamp can be moved when the nonce is exhausted even if the actual time is not that ...
Ava Chow's user avatar
  • 70.9k
3 votes
Accepted

Total number of hashes performed for bitcoin purposes?

Assuming the numbers in the link are correct, then I think this would be right. I got the same result by multiplying every entry by (1,000,000,000,000 * 3600 * 24 * 2) and adding them up. Came out to ...
Luke Mlsna's user avatar
3 votes

Why am I getting only about 3k to 300k hashes per second?

You are limited by your machine clock speed and hashing library performance. Scripting langs are not a good choice for CPU intensive operations. Also, you are doing hashes sequentially, try ...
vent's user avatar
  • 151

Only top scored, non community-wiki answers of a minimum length are eligible