Homework on Stale Blocks

Blockchain and Bitcoin 101
#1787

  1. What happens in the bitcoin network when two miners solve a block at the same time?

  2. What is a stale block?

  3. How do stale blocks occur?

  4. Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?

  5. When 2 miners solve a block at the same time the block (chain forks temporarily)in the longest chain wins and the other block is discarded and considered a stale or orphaned block. All the transactions are returned to the mempool.

  6. A stale block is the block that was in the blockchain but then dropped(put back into Mempool) because another block that was produced at the same time was part of a longer chain(more PoW).

  7. Stale blocks occur when a block was valid for a while because 2 were produced with the same version of the truth(forking) but then dropped because the blockchain continued on another block(longer chain).

  8. It is important to wait for 6 confirmations to be sure that the block your transactions are in is not(forked and remains in the shorter chain and)dropped from the chain.

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#1788

  1. They are competing to stay in the chain and once one of them gets a block added to his block and it is accepted, the other person’s block will be dropped.

  2. a dropped block

  3. Stale blocks occur when 2 miners complete a block at the same time and only one of their blocks is accepted into the chain.

  4. To see if the chain has been accepted by the network. 6 confirmations is ideal.

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#1789

  1. What happens in the bitcoin network when two miners solve a block at the same time?
    It temporarily splits the chain and only the longest chain will be accepted by the network.

  2. What is a stale block?
    A stale block is a block that was once apart of blockchain but was dropped once the split in the chain that doesn’t contain said block is validated into the network.

  3. How do stale blocks occur?
    Stale blocks occur when the blockchain splits due to two miners mining the same block at the same time and the chain that is shortest by the time the block time is up, will be dropped and all the Tx’s in those blocks will return to the mempool.

  4. Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?
    To reduce the number of stale blocks that occur

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#1790

  1. The miner with the longer chain gets accepted in the network and the other gets rejected.

  2. A stale block is a valid mined block that was cast out of the network because of another block being accepted in the network. They get recycled in to the mempool.

  3. A stale block has less chains than the blocks that replace them.

  4. The network expects 6 blocks to be mined in order for them to be accepted into the network and have them propagate via the nodes. That takes 10 min and depending on the traffic would sustain the network to keep the difficulty level in check.

#1791

Blocks get mined approximately every 10 min, so 6 * 10 is one hour and the block gets propagated as soon as it gets mined, in case of a split some nodes will get one block and some will get the other block, the physical distance is what makes this an issue but eventually gets resolved.
Waiting 6 confirmations is a good rule of thumb to be sure the block will not get dropped and any potential splits have been resolved up to that block :slight_smile:

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#1792

  1. The blockchain splits into two chains - the longest chain will win, the shortest will be dropped.

  2. A stale (or orphan) block is a block that gets dropped (it is not in the longest chain) - all the txs go back in the mempool

  3. Stale block occur when two miners produce two different (but valid) blocks at the same time. The blocks are then propagated to the network (nodes).

  4. Because the possibility of stale block decrease’s (forks)

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#1793

Stale blocks are probable in any case. Waiting for a few confirmations decreases the probability of our tx being part of it or if it was that the fork has been resolved by then. :slight_smile:

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#1794

Thank you for the correction, off course you are right (i was a little to fast with the answer and didn’t think it entirely thought :relaxed:)

Good evening from Kamnik :wink:

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#1795
  1. Only 1 miner can win. The longer of the two blocks will be confirmed.
  2. A stale block is a dropped block also called an orphan block.
  3. Stale blocks occur when they are part of a shorter chain and are not confirmed by the network.
  4. It’s important to wait for 6 confirmations when sending or receiving a transaction to avoid stale or orphan blocks.
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#1796
  1. The version of the blockchain that has the longest chain by proof of work will be the one accepted by the system.
  2. A valid block dropped because a longer chain by proof of work was accepted instead.
  3. when 2 miners solve a block at the same time and one is accepted and one is rejected. the rejected block(s) become stale blocks.
  4. Because your block could be a stale block by chance.
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#1797

#1.- If both miners have solved the target and have needed nonce , they must
wait for a 3rd miner to chose 1 and add on to chain thus making them the
longer chain.
#2 - A block dropped or not added to blockchain is deemed “Stale” or
“Orphaned”
#3.- when an event such as described in #1 happens, the block not chosen
then become “Stale” or “Orphaned” and transactions within removed ,
returned to mempool.
#4.- to really count on block added to chain will stay on the chain , you should
wait for 6 blocks to be added to chain for confirmation

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#1798

  1. The network looks for the longest chain between the miners and will validate that block. The not excepted than goes into a mempool waiting for a miner a take those transactions into another block they want to create.

  2. a stale block is one that was reject and sent back into a mempool.

  3. Stale block occur when multiple miners are trying to get their block accepted into the blockchain and one of the blocks are rejected from the blockchain.

  4. This helps to insure that the block with the transactions is truly accepted in the blockchain and does not become a stale block.

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#1799

  1. Both block are added to the latest version of the truth and communicated to the nodes in the network. Now, two versions of the blockchain are in existence. After a period of time, the longest chain will be accepted as the latest version of the truth.

  2. A stale block is a mined block that got rejected by the network over time

  3. When miners add multiple blocks at the same to time to the blockchain. The shortest chains will be rejected and send back to the mempool

  4. Then you are sure the block is truly accepted in the blockchain and that it will not be send back to the mempool.

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#1800

  1. The network gets two versions of the truth, and depending on which block the next miner choose to build it’s own block upon creating the longest blockchain will be the ‘‘truth’’ and one version of the truth will be removed(the shorter blockchain).

  2. It’s a dropped/removed block which is valid and verified but didn’t make it to the blockchain because of being a shorter blockchain or due to timelag.

3.When two miners mine different blocks at the same time creating two different versions of the truth.

  1. To be 100% sure that your transaction will come through.
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#1801
  1. What happens in the bitcoin network when two miners solve a block at the same time? Both miners start propagating their mined block to nodes in the network, which results in two versions of the blockchain competing to become the longest blockchain accepted by the entire network.
  2. What is a stale block? A block that has been dropped from the blockchain after being mined.
  3. How do stale blocks occur? Two or more blocks get mined at the same exact time, with the shorter version of the blockchain getting dropped for the longer version accepted by the entire network.
  4. Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction? To ensure that your transaction doesn’t get dropped from the blockchain and returned to the mempool.
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#1802
  1. When 2 miners solve a block at the same time,it might result temporary in the creation of 2 parallel blockchains. Some nodes will get one of the last blocks, some other nodes will get the other block.
  2. A staled block is a completely valid block which has been dropped because his version of the blockchain was less efficient to inform enough nodes in time.
  3. Stale block occurs when 2 miners mine a block at the same time. Some block are then dropped in order to keep the blockchain consistent… these are called staled blocks
    4)By waiting that more blocks get confirmed before sending or receiving a transaction, this helps to make sure that the mined block wont get staled.
#1803
  1. One block becomes an orphaned block (Charlie Lee uses it on twitter) and one goes on chain.
  2. A stale block is a valid set of transactions that is not added on the blockchain, thus it is orphaned (no home chain) and the transactions return to the memepool.
  3. Two blocks are globally created at close to a simultaneous moment and one is accepted and one is not. Then a new block is added on to the chain and the orphaned block is returned to the memepool.
  4. To ensure that the transaction is on chain and not on a potentially orphaned block.
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#1804
  1. When two miners solve a block at the same in the bitcoin network, one of the blocks, the shorter blockchain, will get dropped and become a stale block and all the transactions will be returned to the mempool.
  2. A stale block is a block that was in the blockchain at one point but got dropped because there was another version of the blockchain without that block in it.
  3. Stale block occur when two miners solve a block at the same time and other miners build upon one of them and the other gets dropped.
  4. It is important to wait for more than one block to be confirmed when sending or receiving a transaction because you don’t want your transaction to end up in a block that will be dropped.
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#1805

There will be two valid versions on the network. The network accepts the longest block chain with the most POW.

A block that was in the block chain at one time but dropped.

When there are two versions on the network. The shortest & least POW becomes stale, gets discarded and transactions returned to the mempool.

It’s best to wait for at least 6 confirmations after your block because there is a chance that your transaction could be in the block that is dropped

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#1806
  1. The one with the longest chain will be chosen and the shortest one dropped.
  2. The block dropped from the blockchain due to another block having a longer chain.
  3. When a valid block is mined by 2 miners, the miner with the shortest chain is not selected and is considered a stale block or orphaned.
  4. To avoid your transactions from being part of a stale block.
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