Homework on Stale Blocks

Blockchain and Bitcoin 101
#960

What happens in the bitcoin network when two miners solve a block at the
same time?
The chain forks into 2 until one of the chains becomes longer which will become accepted as the continuation of the chain. The other fork will be discarded.

What is a stale block?
This was a valid block in the chain but was later discarded

How do stale blocks occur?
When a different for of the blockchain becomes longer and invalidates this one.

Why is it important to wait for more than one block to be confirmed when
sending or receiving a transaction?
To ensure the block with your transaction does not become stale.

1 Like
#961
  1. This creates two versions of the truth. A few minutes later one of these versions will be chosen by the upcoming blocks.
  2. The stale block is the version of the truth that was not chosen by the new block. The stale block gets sent to the mempool to wait in line again to be picked by a miner.
  3. Stale blocks occur when the chain splits because of two miners completing a block at the same time. One of these blocks will continue the chain when new blocks add on to it, meanwhile the other block that was not chosen by the new blocks will have less POW so it gets sent to the mempool. That is the stale block.
  4. That’s because when the block is deep in the chain by at least a few blocks, we know that it will not be changed. It is a confirmed transaction. That is why it is recommended to wait 10 min or a few blocks to make sure a transaction is confirmed.
1 Like
#962

Stale Blocks Homework

  1. When two miners solve a block at the same time both are valid, but sooner or later another miner will choose on over the other and that one will have longest blockchain with most PoW and this is the version of truth accepted. The one rejected will go to Mempool and be considered an orphan/ stale.
  2. A stale/ orphan block is the version of truth not accepted by the network; the transaction in a block that is dropped.
  3. Stale blocks occur when two miners propagate blocks through network at the same time and are valid, but one of them is removed and returned to the Mempool because it is shorter and rejected over a competing longer version of truth.
  4. It is important to wait for more than one block to be confirmed because it might be the case that your transaction is in a block that may be dropped. Waiting about ten minutes or six blocks allows new block to be validated.
1 Like
#963

  1. Both blocks will be sended to other nodes

  2. Then miners mine those blocks again, but only the block with the longest chain will be accepted. The other block will get dropped = this one is called stale block

  3. see 1. and 2. = when 2 miners mine the same block at the same time

  4. if you don´t wait for more confirmations, your transaction can be in a stale block and gets dropped.

1 Like
#964

  1. It will propagate the network and the first block to be re-mined upon will create the longest chain and will be accepted in to the chain- the longest chain wins

  2. A block that is not accepted into the chain by not being fast enough- these blocks will not push transactions that did not make it into winning block and the transactions will stay in the mempool.

  3. By being processed to slow and not being accepted into the network- by not being the part of the longest chain.

  4. To ensure your transaction has made it into a winning block chain- That the chain has been successfully accepted into the network across the world(you require 6 confirmations before it is finite).

#965

1. What happens in the bitcoin network when two miners solve a block at the same time?
There are basically two versions of the blockchain, and is needed a next block to define which chain will be the accepted one.
2. What is a stale block?
It is a block that has been discarded.
3. How do stale blocks occur?
It occurs when two or more miners mine a block at the same time and there are two (or more) chains, so then the chain with more pow is selected and the other one is discarded. The last block from the discarded chain is discarded too and receive the name of 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 probabilities that the block where your transaction is will be discarded are exponentially lower for each block that is added.

#966
  1. They both add it to the network, creating a fork.
  2. A stale block is the one dropped from the Blockchain.
  3. Stale blocks occur because they were not in the longest chain
  4. Because it may be dropped if its not confirmed by most of the network
#967
  1. Two are created!
  2. One that is dropped.
  3. Because they’re two blocks added at the same time.
  4. Because you wanna make sure that you’re block doesn’t get dropped and sent back to the dreaded mempool!
#968

  1. What happens in the bitcoin network when two miners solve a block at the same time?
    When two miners solve a block at the same time on the bitcoin network it creates a duplicate block.

  2. What is a stale block?
    A stale block or or orphan block is one of the duplicate blocks that are dropped when two miners solve a block a the same time.

  3. How do stale blocks occur?

A stale block occurs when two miners solve a block on the bitcoin network at the same time, and one of those duplicate blocks needs to be discarded to create a stale block.

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

This will allow you to confirm that none of the blocks in your transaction were stale, and assures that you are one the longest part of the block chain.

#969

  1. You now have two blocks on the blockahin going two different deirctions

  2. When the next miner chooses one block. so the block left goes back to the mempool

  3. Just it case it isnt a stale block

#970
  1. a temporary fork in the blockchain and the chain thats longest wins. the losing chain is put back to the mempool
  2. blocks that are no longer part of the blockchain
  3. when two miners solve a block at the same time
  4. the practice is to wait for 6 blocks to be confirmed as this will be the best version of the truth
#971

1 the protocol will choose the longest chain and the other will be discarded and the transactions send to the mempool.
2 The stale blocks are the ones that where discarded, because another chain has a longest chain.
3 Went 3 miners found a solution at the same time, one of the chains (the longest one) will remain and the others will be stale blocks.
4 Because in the case that two miners solve the block at the same time, it is possible that your transaction is in shortest chain.

#972

  1. What happens in the bitcoin network when two miners solve a block at the same time?
    There could be a problem in that different miners may choose alternative mined blocks and the blockchain then becomes forked. The miner who next completes a block will link to one of the forks thereby creating the longest chain and the redundant block will be discarded

  2. What is a stale block?
    A stale block is the block described above that is discarded as it no longer forms part of the longest chain

  3. How do stale blocks occur?

The blockchain takes too long to propogate to nodes providing the opportunity for 2 different miners to successfully mine a block and potentially create a fork
4. Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?

This is to avoid a transaction being rejected because it did not form part of the longest chain . Confirmation provides assurance that the transaction is in fact included in the blockchain

1 Like
#973

  1. What happens in the bitcoin network when two miners solve a block at the same time?
    There are two versions of the chain then. The one that is longer is being approved.

  2. What is a stale block?
    That is a block that was created the same time with another one but wasn’t approved by the block after that.

  3. How do stale blocks occur?
    When solving a nonce by two miners at the same time. The two blocks are true version for a while.

  4. Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?
    For a confirmation is needed 6 blocks of time because that would be enough to elongate the true chain.

1 Like
#974

  1. When two miners solve a block in the bitcoin network at the same time the block in the longest chain wins and the other block is dropped this then becomes a stale or orphaned block and all the transactions then return to the mempool.

  2. A stale block is a completely valid block that was in the blockchain but was dropped because another block which was produced at the same time had a longer blockchain. (longer blockchain wins)

  3. Stale blocks occur when a two blocks are produced at the same time but one joins the blockchain and the other is dropped. The winning block joins the blockchain because it is part of the longer chain.

  4. It is important to wait for more than one block to be confirmed preferably 6 because then you can be sure that your block won’t be dropped and will remain part of the longest chain.

#975
  1. What happens in the bitcoin network when two miners solve a block at the same time? The block with the longest chain wins
  2. What is a stale block?
    A block that was produced at the same time as another succesful block and is idscarted due to the absence of ussage
  3. How do stale blocks occur?
    When two blocks are added at the same time to the blockchain but the next block is only added to one of the two the shorter one is then discarted
  4. Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction? It is important to wait for 6 confirmations to make sure that the block the transaction is in is not discarted
1 Like
#976

both blocks get appended to blockchain

a perfectly valid block that gets sent back to the mempool because a longer version of the blockchain now exists that doesn’t include the stale block

because the nonce of two blocks are solved by different miners at the same time

to avoid the risk of your transaction being in a stale block (that gets sent back to the mempool)

#977
  1. When two miners solve a block at the same time, the nodes of each miner say that their miners blockchain is the only chain. One miners nodes do not know the other miner exists.
  2. A stale block is a block that has dropped.
  3. Stale blocks occur when a new miner joins with one of the two miners sharing the blockchain and is the one which the new miner did not connect.
  4. It is important because the six confirmations ensure the safety of the transaction so it cannot become stale.
#978

1.What happens in the bitcoin network when two miners solve a block at the same time? - both blockchains are valid until one of them has a longer chain the other. The longest chain wins. The orphaned chain gets sent back to the mempool.
2.what is a stale block? - a stale block is a block that was once verified by a miner but later discarded because it was a part of a smaller blockchain.
3.how do stale blocks occur? - stale blocks belong to a verified chain. Once a larger verified chain comes along, the smaller chain is discarded.
4.why is it important to wait for more than one block to be confirmed when sending or receiving a transaction? - waiting for atleast 6 blocks is recommended to make sure the transaction does not go stale.

1 Like
#979

they both begin propugating through the network until one is ultimately dropped

A stale block is a confirmed block that has less POW than a similar block mined at the same time

A stale block occurs when two blocks are mined at exactly the same time

Because if the block that contains your transaction, which contains one confirmation, becomes stail the transaction will be placed back into the menpool. Thus the transaction will revert to having zero confirmations.

1 Like