Homework on Stale Blocks

Blockchain and Bitcoin 101
#602
  1. What happens in the bitcoin network when two miners solve a block at the same time?
    It creates to blocks. A confirmed and a stale block
  2. What is a stale block?
    A block that got canceled and had send all the transactions to the mempool
  3. How do stale blocks occur?
    When to miners solve a block in the same period of time
  4. Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?
    To get rid of the stale blocks and get all the physical information propagated around all the network
#603

  1. What happens in the bitcoin network when two miners solve a block at the same time?
    It depends, if the new miner joins, the one with the longest chain will be selected and other will be discarded.

  2. What is a stale block? The validated and discarded block from the blockchain.

  3. How do stale blocks occur? When two miners try to validate the same block at the same time.

  4. Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction? So that longest chain would appear and will be given a preference based on the difficulty level solved and block transactions are not dropped. Ideally its better to wait for 6 confirmations. And if transactions while mining are not confirmed it will be sent back to the mempool.

#604
  1. the one with the longest block-chain will be added to the network.
  2. is a discarded block .
  3. by two version of the truth or block-chain being produced or propagated in the network and maybe blocks being produced prior to the 10 mins. Blocks being produced prior to six confirmations and prior to the correct version of the truth having to propagate through the network.
    4.to avoid having stale blocks usually having 6 confirmations will validate a block properly .
#605

  • What happens in the bitcoin network when two miners solve a block at the same time?
    Both blocks are valid so will be accepted into the network by the nodes physically closest to the miner.

  • What is a stale block?
    A stale block is a block that is rejected from the network. All of the transactions within a stale block will be returned into the mempool.

  • How do stale blocks occur?
    A stale block occurs when two versions of the blockchain begin to propagate through different physical parts of the network. 1 version will eventually have another block appended to it and that longer version of the blockchain will be recognized by the network as having the most proof of work. The last block of the alternate blockchain will be discarded by the network and it becomes an orphaned block with all its transactions being returned to the mempool.

  • Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?
    This is to confirm that you are not observing a block that may potentially be orphaned. More subsequent blocks added onto the block in question makes the probability higher that it is in the accepted version of the blockchain.

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#606

  1. One will win the longer blockchain will be continued. The short Blockchain will be dropped.

  2. a stale Block is a valid block which is not accepted by the longest running blockchain.

  3. When the network updates the blockchain, there just can be one true Blockchain. So when every node is in sync, some nodes might have to drop blocks because they are working on the shorter blockchain.

  4. Because it reduces the probability that the block become not accepted in the blockchain. It is important to be on the longer blockchain, if not the block will be dropped and the transactions go back to the memo pool, waiting there, to get picked up again by miners.

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#607

  1. Only the miner with the longest blockchain which solved the block will be accepted as valid.

  2. Dropped unaccepted block.

  3. The blocks are being mined in less than 10 minutes and miners do not get enough time to receive,
    validate and be ready to receive the next block. Simultaneous solving of the block puzzle by 2 or
    more miners.

4.Stale or orphan blocks created later may be dropped later.

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#608

  1. Both blocks will be added to chain for a while and later the next arriving block will determine which block is valid and other became an orphan block (all TX concluded in orphan block will be returned to the mempool).

  2. A Stale/Orphan block is the block which was legally added to the chain and later removed, due to splitting between parallel blocks. When parallel block connects a next block faster and constructs the longes chain stale block is removed.

  3. Since, blockchain is distributed physically through the internet a distances, internet speed and other properties matters in time at which nods gets a latest version of the blockchain. At that case, when two different nods creates a new block and adds to chain, exists two different chains in system and both of them is valid.

  4. 10 minute is the optimal time to minimise possibility that your transaction ended up in stale block. In that time enough blocks can be created and added to chain to make a winner chain.

#609

You can’t minimize the possibility that your transaction was in a stale block with time. Time does not matter, blocks do. In order to make sure your transaction is not gonna be in a stale block you would want to wait for 6 block confirmations.

#610

  1. The network will choose the longest chain and the other block will go to mempool.

  2. Stale block is a block that was once a valid block also known orphan block.

  3. A stale block happens when more than one miner mines a block simultaneously. The block that goes on to form the longest chain is confirmed and the other becomes a stale block.

  4. To ensure that your tx is included in a block of a valid block chain and not in a stale block.

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#611
  1. What happens in the bitcoin network when two miners solve a block at the same time?

Nodes closest to each miner pick up solutions and then wait for confirmation. always the longest chain wins

  1. What is a stale block?

Valid block without confirmation with the shortest chain. not accepted by the longest blockchain

  1. How do stale blocks occur?

When miners solve a block at the same time

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

To avoid being part of a smaller blockchain and therefore stale block we would want to wait at least 1 hour (6 confirmations of 10 mins each)

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#612

  1. Both miners will propagate their block which results in some parts of the network knowing one truth while the other parts accept another truth as correct.

  2. Stale blocks previously belonged to one branch of the split blockchain but do not anymore.

  3. Stale blocks occur when the scenario in point 1. was resolved. Which happens when the next block is mined on any of the branches of the split blockchain. The network accepts the chain with the most proof of work as the new truth, all other branches are dropped and their competing blocks become stale.

  4. Although unlikely, since most miners will chose the same transactions, a transaction may drop because it was included in a block that is now stale. However, this situation will resolve itself automatically. If the transaction wasn’t included in the block of the other chain it will be put back into the mempool and included in one of the next blocks.

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#613

  1. Both blocks will start to propagate through the network.

  2. Blocks that were dropped from the chain. The transactions will return to the mempool.

  3. When a competing block is chosen by the next. This makes the chain longer than the other block so it is removed.

  4. The transaction could be part of a block that gets removed.

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#614

1. What happens in the bitcoin network when two miners solve a block at the same time?
Both blocks are valid, but eventually the network will choose the longest chain, and the other block will become stale/orphaned.

2. What is a stale block?
A stale block is a block that wasn’t taken by the blockchain. The transactions listed in the stale block head back to the mempool.

3. How do stale blocks occur?
There can only be one source of truth. When two blocks are solved at the same time, it creates a situation where there are two chains. Eventually the longer chain will be adopted, creating stale block in the invalid chain.

4. Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?
It is best to wait for confirmations of more than a single block to be confirmed, just in case the block becomes stale and the transactions head back to the mempool.

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#615

  1. both are distributed to the network and as long as they are both good, they will both be accepted until another block is mined off of one of them, then that one will have a longer chain and with be accepted as the one that is true.

  2. A stale block is one that is dropped from the chain and its transactions have been returned to the mempool.

  3. Stale blocks occur after a longer chain has been created elsewhere so that the chain that that block is on is no longer the accepted true chain.

  4. It is important to wait for more than one block to be confirmed so that you are more sure that your transaction has gone through and is going to permanently stick in the blockchain and not end up being on a stale block.

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#616
  1. the verification nodes come to consensus as to the miner that built the longer chain. The longer chain is accepted and the transactions of the shorter chain are orphaned.
  2. a block that was part of the shorter chain that was rejected
  3. when two competing miners arrive at a valid solution to the problem quickly enough and begin propagating their blocks to verification nodes causing a chain split. The longest chain is considered valid, and the shorter chain, and all of its transactions, are considered invalid, or stale.
  4. because your receiving transaction could be invalidated if the containing block becomes stale.
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#617

  • What happens in the bitcoin network when two miners solve a block at the same time?
    One will eventually be rejected. The shortest chain will be orphaned and dropped.

  • What is a stale block?
    A block that is dropped or orphaned because it is not on the longest chain.

  • How do stale blocks occur?
    When miners create blocks at the same time and propagate the network, one will propagate faster, start mining a new block, and eventually create a longer chain. The shorter chain will have blocks that will get dropped, otherwise known as stale blocks.

  • Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?
    You don’t want your transaction to end up in a stale block.

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#618

1.-
Two versions of truth. This situation is solved with time and while the number of blocks grows, been the longest chain the one that will be accepted.

2.-
The ones that are discarded.

3.-
When two or more blocks are generated by distinct miners almost at the same time. Since the propagation of this new blocks takes time, this two valid versions of the chain can arise.

4.-
Because of the possibility of a transaction to end up on a stale block it is better to wait at least 6 new blocks (around an hour) to be sure that is not the case.

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#619
  1. depending on which block the next miner chose 1 block will be invalidated.
    2… a stale block is the block that gets invalidated when 2 blocks were mined at the same time, it is a emty block that disconnected from the blockchain.
  2. when two miners mine 2 blocks at the same time, one block gets droped in the next 10 min as soon as the next block is mined, the droped block is then called a stale block.
  3. because if a block becomes stale the transaction will be sent back to the mempool and your received funds may be no more.
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#620

  • What happens in the bitcoin network when two miners solve a block at the same time?
    Both are then appended to the blockchain because the nodes in their vicinity are accepting them as the validated truth. Eventually one of the new miners in the vicinity of one of those propagated blocks will append their block to one of those truths. At that point the network accepts the longest chain of complicated solved blocks, and the shortest chain will be deleted.

  • What is a stale block?
    A block that has been validated as the truth, bust eventually has been deleted because it was part of a shorter chain.

  • How do stale blocks occur?
    By minors who solve their puzzle at approximately the same time.

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

The advice is to wait for at least six blocks to be confirmed to reduce the risk of your block being a stale block as mentioned above.

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#621

  • What happens in the bitcoin network when two miners solve a block at the same time?
    -There is temporary two versions of truth… When the next miner adds another block to the chain, the block that he picked between this two to add his block on is being accepted as true, because then it becomes the longest PoW.

  • What is a stale block? - A stale block is block that was temporarily accepted and later dismissed.

  • How do stale blocks occur? - Once it happens that two blocks are accepted to the chain in the same time, only one can continue the chain because there is only one version of the truth. Once a miner creates a new block and he picks one of this two blocks that were added the other one is being dismissed by the whole blockchain, and we call it stale block.

  • Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction? - Because it is possible that our transaction was in one of the stale blocks, and the information needs time to travel through the network.

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