Homework on Stale Blocks

Blockchain and Bitcoin 101
#2029

  1. In such a situation the block, which will succeed in getting propagated faster and will have the longest chain consequently linked to it, will be accepted by the network.

  2. The stale block is the block dropped from the chain.

  3. Some legitimate blocks are sometimes dropped and removed from the chain because of the fact, that the tree node they were part of has been rejected by the network due to the fact that on of its competing nodes proved to be the longest in the chain.

  4. In order to be sure that the node your block is a part of will prove to be the longest one in the chain and will be accepted by the network.

1 Like
#2030
  1. One of the blocks will be dropped. The longest/strongest chain wins.
  2. The block dropped, is a stale block.
  3. When 2 miners, mine a block at the same time. Then one gets dropped=stale block
  4. 10 min block times to aviod stale blocks.
1 Like
#2031

  1. Both of those blocks begin to get propagated throughout the network and once another miner begins building on one of the blocks, the version of the blockchain with the most proof of work will be the one one that is accepted and the other block will get dropped

  2. The dropped blocks are what are referred to as stale blocks

  3. Stale blocks occur from the example in the first question

  4. So you know that the block with your transaction won’t get dropped

1 Like
#2032

  1. The one who has the longest blockchain wins eventually and the other one will be orphaned.

  2. A stale block is the one which is dropped in the blockchain when another block is produced at the same time which is the longest blockchain.

  3. Stale blocks occur when the same block is mined by two different miners at the same time and only one has to validate the block and the other one will be invalidate.

  4. The block shouldn’t be dropped from the chain during the transactions otherwise the orphaned block will be occurred.

1 Like
#2033

The blocks mined are not the same, they can contain completely different transaction. It is just that the correct (different) nonce was found by two miners for a block at the same height. :slight_smile:

1 Like
#2034

Thank you for correcting.

#2035
  1. Two versions of blockchain are created;
  2. Stale block is a valid block that one was in blockchain, but a different version of blockchain got longer;
  3. Stale block occure when another version (with diffrent blocks) of blockchain got longer;
  4. In case your transaction was included in a block that became stale, but no in any of longest chan blocks.
1 Like
#2036

  1. When two miners solve a block at the same time, two blocks are produced which means two versions of the blockchain is produced (both are true but may contain diffetent transactions). The closest nodes receicve the information about the new block(s) and are able to continue. The determining factors for the creation of new blocks into each other of the differig blocks include mining difficulty and speed.

  2. A stale block is a block that is true or verified but miners decided not to continue to add another block to that chain.

  3. When two miners solve a block at the same time,
    Nodes cloest to the miners receicve information first that the blocks are solved and two blocks are created. Miners can then chose which block to continue to build upon. The block that miners continuously adds blocks to is the longer chain and is thus excepted by the network.

  4. It is important to wait because Bitcoin is a world wide network and it takes 10 min to 1. Solve Cryptographic puzzle, 2. Add blocks 3. Allow worldwide networks to receive and update information. In the case of stale blocks transactions that were ‘only’ in the stale blocks return to the mempool.

1 Like
#2037

  1. What happens in the bitcoin network when two miners solve a block at the same time?
    When this happened the longer block will win. The one with more POW

  2. What is a stale block?
    It’s a block that was part of the chain and got invalidated for a longer block, so its gets dropped from the chain and sended back to the mempool.

  3. How do stale blocks occur?
    When there are 2 versions of the truth in the blockchain, the shortest one have to get invalidated.

  4. Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?
    So you can make sure that it doesn’t get invalidated for another block.

1 Like
#2038
  1. What happens in the bitcoin network when two miners solve a block at the same time?

a fork in the chain is formed

  1. What is a stale block?

an invalidated block

  1. How do stale blocks occur?

they occur when the blockchain when the block on the other “fork” of the blockchain (the other block that was mined at the same time as another block the soon-to-be “stale block”) is accepted by more nodes on the network and has additional blocks added to it, becoming the longer chain

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

to help mitigate the possibility that the block that your transaction was included in is not invalidated (made stale) by another version of the blockchain (becoming the longer one, and thus the “true” chain)

1 Like
#2039
  1. When two miners solve a block at the same time the blocks go to be added to network but the nodes closest to each miner get that version of the block and the network chooses the block with the longest chain for consensus.
    2.3 a valid block that gets sent back to the mempool for not being a part of the longest chain
    4.Minimizes the odds of creating orphan blocks
1 Like
#2040

The chain creates 2 blocks when two miners solve a block at the same time, and then whichever block is mined next dictates the longest chain that the blockchain will then base itself off of moving forward. The block that was not used to be based off of for future blocks is considered a stale block, and its transactions are sent back to the mempool.

It is important to wait for more than one block to be confirmed when sending or receiving a transaction, because it is possible the transaction may be dropped should a stale/orphan block occur. After 6 confirmations, it is likely the transaction has been successfully mined in a regular block.

1 Like
#2041
  1. What happens in the bitcoin network when two miners solve a block at the same time?

Both blocks are added onto of the previous block, but on separate chains. One of the two blocks is then eliminated after ~10 min when another block as been solved and added to the “winning” chain.

  1. What is a stale block? & 3. How do stale blocks occur?

The stale block is the block that was true and yet dropped from the chain as it held the same place as another “true” block, which had an additional “true” block added onto it earlier. This next additional block made the chain longer, and the longer chain become the valid chain.

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

The tx block may become stale due to forking and send it back to the mempool.

1 Like
#2042
  1. When two miners solve a block at the same time, the network will go with the block that has most proof of work connected to it.
  2. the block dropped (B)
  3. For example, if one block by miner A already has a number of blocks with higher difficulty/more pof attached to it than block by miner B, the system will take the block by miner A and drop B and block B is called the stale block.
  4. so that we don’t end up with two of the same blocks being created and then being built upon at the same time
1 Like
#2043

Both chains continue to get mined and it also might happen that again a block on both chains gets found at the same time (less likely). The reason you want to wait for these forks to get resolved is because your tx might be part of it.
If this is the case an attacker could use the opportunity to double spend the UTXO used in the tx that has been dropped back to the mempool :slight_smile:

1 Like
#2044

  1. What happens in the bitcoin network when two miners solve a block at the same time is that one of those blocks becomes “stale(orphaned)”

  2. A stale block is a block that was valid, but was not picked by miners to be part of the valid chain.

  3. Stale blocks occur when 2 miners find a valid nonce at the same time, but since only one of those blocks can be added to the chain, the other block goes stale and is put into the mempool.

  4. It is important to wait for more than one block to be confirmed when sending or receiving a transaction because then your transaction will be put into the valid chain and won’t go stale.

1 Like
#2045

1.What happens in the bitcoin network when two miners solve a block at the same time?
Both of the block will start to spread into the network. Some other nodes will have one block and the others will have the other block. Miners will keep adding blocks to continue the chain.

2.What is a stale block?
It is a block that has been rejected from the main chain.

3.How do stale blocks occur?
When there are multiple blocks added to the chain, both continues until 6 blocks are added. And the chain that reaches the first will remain as the main chain and the other becomes the stale block.

4.Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?
Because the chain you are going to join might become a stale block or chain.

1 Like
#2046

  1. When two miners solve a block at the same time, those two blocks are propagated through the network, essentially creating two momentary versions of the “truth” of the blockchain

  2. A Stale Block is a block that gets discarded by the network because it was part of a shorter version of the blockchain than another version already being propagated

  3. Stale Blocks occur when miners reach a valid nonce at approximately the same time and propagate their blocks concurrently. Since only one version of the blockchain may survive, the last block(s) that was/were part of a rejected blockchain will be stale blocks

  4. It is important to wait for more than one block to be confirmed when sending or receiving a transaction because that transaction may have been part of a block that might still be considered a stale block, and consequently be discarded to the Mempool. Only time will tell if the block where that transaction was included will be part of the official blockchain, so to make sure a transaction is actually confirmed, the network should wait for some other blocks to be mined “on top” of that block where it was included

1 Like
#2047
  1. Only one miner shall win and other miner solution shall be rejected. so we wait for next longer chain of two chains whichever is longer will win as now the miner blockchain entry will now supports longer chain data.
  2. Like 2 miner solve block together and one miner block was not accepted it is a stale block or orphaned block.
  3. This confirms the transaction as the chain now becomes longer and miner will confirm the longer blockchain so after a block is added on the last block the transaction will likely to fail unless there is a longer chain in comparison to current existing chain.
1 Like
#2048

  • they create 2 different version of blockchain

  • a stale block is a block that was ok in every aspect but it get rejected from the network/blockchain.

  • because there is a rule that the longest blockchain is the truth so: stale block occur when a version of blockchain that is actually longer and more mined surpass and get longer then another version of blockchain

1 Like