The Bitcoin confirmation time - the time it takes to mine a block of Bitcoin transactions - fluctuated by several minutes over the course of A Bitcoin transaction is confirmed. On the Bitcoin network, the average confirmation time for a BTC payment is about 10 minutes. However, transaction times can vary. ETHEREUM ACCOUNT NUMBER
This is roughly like a tree falling in the forest with nobody around to hear it. However, sending the signed statement only to Bob is not enough, because Alice could have signed a conflicting transaction saying she wants to transfer the coins to Carol which she only sends to Carol. If Bob and Carol both accepted these statements as indicating that they have received the coins from Alice, then Alice will have effectively spent her coins twice!
This is where the idea of a global ledger comes in. If Alice wants to transfer her coins to Bob, she must publish her statement authorizing the transfer to the blockchain. The miners who maintain the blockchain will only include this transaction if Alice has not yet transferred the coins to anybody else, so once Bob sees the transaction appear in the blockchain he can be confident that he is the new owner.
Even if Alice later tries to produce a statement saying she transfered the coins to Carol, it will never be accepted into the blockchain because the transaction transferring to Bob was published first. Unfortunately, the blockchain does not offer strong consistency , meaning that any data included in the blockchain is guaranteed to be included forever. For technical reasons, the blockchain offers a weaker property called eventual consistency , meaning that eventually all parties will agree on the blockchain up to a certain ever-increasing prefix.
Put another way, the blockchain is a series of n blocks currently almost , , and at any given time the most recent several blocks are not guaranteed to be permanently included. It is possible for the blockchain to fork by having multiple potential often inconsistent blocks which claim to be the last block in the chain. When an apparently valid block is replaced by a competing block, this is called a blockchain reorganization and the replaced block is called an orphan block.
However, it is possible although rare for the last n blocks to be orphaned in a reorganization. This is exponentially less likely to occur the larger n gets. It typically happens multiple times a day, for example, that a single block is orphaned, but has happened only a few dozen times in history for n between 2 and 4, and exactly once for n greater than 4 a block reorganization in March due to a technical glitch.
Barring technical glitches, formal modeling of Bitcoin suggests that large reorganizations are exponentially unlikely, but possible. In practice, the community has adopted 6 blocks as a standard confirmation period. For relatively small transactions like buying coffee , users might be fine with a shorter confirmation period such as one or even zero blocks. Assuming Alice is fine with the community standard of 6 blocks, how long will she have to wait? Because blocks are found by a random process, there is no telling precisely how long it will take for 6 blocks to be found.
On average, it takes about 10 minutes to find each block. The average block time can actually be slightly shorter or longer depending on if the total hash power of the Bitcoin network is growing or shrinking. Ignoring this detail though, this is why 6 confirmations take about 1 hour on average. However, the block-creation or mining process is random and each block may take much longer or shorter. At a high level, a transaction is confirmed when it is permanently included in the Bitcoin blockchain.
He has taught several university courses on cryptocurrency technology and is currently writing a textbook on the subject. In a way, giving it another stamp of authority. Six confirmations are widely considered to be safe and secure enough to prove your transaction will be valid and permanent.
At this point the chances of your transaction being invalidated are less than 0. New blocks are added to the blockchain through the mining process, which is needed to secure a network and process a Bitcoin transaction. The bigger the value of the transaction, the more confirmations you should wait for as this helps to safely verify a transaction has taken place. It takes an average of ten minutes for each confirmation to come through. Thus six confirmations would take roughly one hour.
If the network is busy, say during a period of high price volatility, it may take much longer. Once a transaction has successfully been made, you should be able to view the transaction details in your wallet with your transaction ID.
0.0022309536 BTC T OUSD
Some mining enterprises may hide their hash power across several mining pools. Also mining ASICs can be temporarily overclocked to increase their hash power. This is less power-efficient but could be used for a brief burst of hashrate. See also: Irreversible Transactions.
Each additional confirmation is a new block being found and added to the end of the blockchain. Miners create blocks by solving the proof of work for their proposed block. The block interval has an average of 10 minutes but not every block interval is exactly 10 minutes. It follows a statistical process known as a poisson process , where random events happen with the same probability in each time interval.
Another way of expressing this is that the mining process has no memory, at every second a block has the same chance of being found. Poisson processes are well-understood but can be unintuative. There are lots of block intervals with a time less than 10 minutes but then a few block intervals much longer which bump up the average to 10 minutes. So the bitcoin network can get unlucky and a block won't be found for a whole hour.
So approximately two-thirds of the time a block will be found in 10 minutes or less. Jump to: navigation , search. Category : Technical. Navigation menu Personal tools Create account Log in. Namespaces Page Discussion. With zero confirmations no proof of work has been done, so you can't tell if anyone considers the transaction valid.
Even with a single transaction it is possible for an attacker to pre compute a single block. With zero or even one confirmation a double spend is very possible since the next block that is solved may confirm a different block instead of the one that has the transaction.
That different block my show the coins being spent elsewhere. The odds that a double spend has occurred gets exponentially smaller with each confirmation. An attacker must match the power of the entire bitcoin network to keep up with block creation so as time goes by it becomes increasingly difficult to forge a transaction. It is generally accepted for most transactions that 6 confirmations represent enough security to assure the transition is valid. If you don't grasp the basic concept, imagine for a second that a network outage split the bitcoin network in half.
I could send one transaction giving 30 bitcoins to Abel to one half and one transaction giving those same 30 bitcoins to Fred to the other. Each half would accept that transaction and until the two halves reconnected, you wouldn't know which transaction would be honored tomorrow. Confirmations are simply blocks that have been generated after the block that contains your transaction. Because there is no central authority that can be consulted to be sure a transaction will be committed, recipients use the number of confirmations as a way of protecting against double-spend attacks.
The network is always trying to extend the longest chain, and eventually, some chain will win. The deeper the transaction is in the chain, the higher the chance it will win because the network tries very hard not to duplicate efforts. Because miners want their coinbase transactions to win, they all try very hard to extend the chain most likely to win, which makes sure it does in fact win.
Effectively, the more confirmations, the higher the likelihood that a transaction will remain forever in the public hash chain rather than a conflicting transaction if there was one. At 6 confirmations, it is perhaps one in a billion that a transaction won't be permanent -- and that's if the sender is attempting a double spend attack.
Sign up to join this community. The best answers are voted up and rise to the top. Stack Overflow for Teams — Start collaborating and sharing organizational knowledge. Create a free Team Why Teams? Learn more. What are bitcoin "confirmations"? Ask Question. Asked 10 years, 7 months ago. Modified 1 year, 3 months ago.
Viewed 45k times. Improve this question. David Ammouial 1, 2 2 gold badges 12 12 silver badges 18 18 bronze badges. Add a comment. Sorted by: Reset to default. Highest score default Date modified newest first Date created oldest first.
Bitcoin network confirmation monero will be the next bitcoin predictionBlockchain Confirmation - How To Verify A Bitcoin Transaction And Get Your Hash ID - BTC
Apologise, but, tigerdirect bitcoin think, that
BITCOIN MT GOX COLLAPSE
Bitcoin network confirmation convert litecoins to bitcoinsWhat are Blockchain Confirmations? Understand Blockchain Technology
Следующая статья will bittrex support bitcoin gold