Homework on Stale Blocks

Blockchain and Bitcoin 101
#4154

What happens in the bitcoin network when two miners solve a block at the same time?
When 2 miners solve a block at the same time the block 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.

What is a stale block?
A stale block is the block that was in the blockchain but then dropped because another block that was produced at the same time was part of a longer chain.

How do stale blocks occur?
Stale blocks occur when a block was valid for a while because 2 were produced with the same version of the truth but then dropped because the blockchain continued on another block.

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 be sure that the block your transactions are in is not dropped from the chain.

1 Like
#4155
  1. What happens in the bitcoin network when two miners solve a block at the same time?
    The longest chain wins and the other transaction will be transfered in the mempool

2.What is a stale block?
These are blocks which were on the blockchain onetime but got dropped after another longer version is produced on the chain.

  1. How do stale blocks occur?
    it occurs when two miners mine at the same time on different blocks, one of the blockchain will be accepted and another will be dropped from the chain.

  2. Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?
    To first confirm your transaction block is not orphaned

1 Like
#4156

What happens in the bitcoin network when two miners solve a block at the same time?
As two different versions of truth start to circulating on the network, one from the block produced by each minner. As new minners start to produce new blocks in the two versions of the blockchain (as if that was two roads to follow), the network will give preference (or control) to the longest road (Proof of Work), witch comes from the version of the truth that was chosen by the most recent block produced. More blocks produced in that same way = more proof of work = more control over the network.

What is a stale block?
It is the name we give to the blocks that were appended to the blockchain but then it was removed by the process described on the question above.

How do stale blocks occur?
When two verified versions of the blockchain starts to dispute over the continuing of the blocks, the version choosed by the minners that introduced the most recent blocks will turn itself in the only version and all the blocks appended to the other version will be removed.

Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?
It is prudent wait for six confirmations after the transaction was appended to the blockchain. It occurs by the time that is demanded to the information phisically travel around the network.

1 Like
#4157

  1. it will get added to the blockchain, but the one that remains is the on with more blocks and difficulty.

  2. It means that the block that once was appended in the blockchain, gets dropped and return to the mempool.

  3. When two different miners get to solve the puzzle at the same time in different parts of the world, and didnā€™t give time to broadcast the block to ll the nodes.

  4. to give the rule of 10 minutes time to avoid stale blocks.

1 Like
#4158
  1. The blockchain is split into two separate versions.
  2. A stale block is a block that has been ignored by the the nodes and has been dropped invalidating transactions back into mempool.
    3.Stale blocks occur when miners are mining blocks too fast. Nodes need for the recent block to be propagated and when nodes choose one version of the blockchain over another it creates the longest chain. The longest chain wins and the other blocks are dropped.
  3. Its important to wait 6 blocks to confirm a transaction because there is a possibility of your transaction being invalidated.
1 Like
#4159
  1. The one that has the 1st link and block attached afterwards to it, which creates a longer chain, wins (is confirmed).
  2. A block that, although in the blockchain, is not confirmed by a subsequent link and block.
  3. When two blocks are solved at the same time, the one that has the 1st link and block attached to it creates a longer blockchain, so the remaining block becomes a stale block.
  4. For assurance that there are no stale blocks, since blocks are constantly being created and the global network is limited to how fast it can sync.
#4160

Waiting will not prevent or assures stale blocks. It only ensures your tx is not part of it.

#4161
  1. What happens in the bitcoin network when two miners solve a block at the same time?
    It gets appended to the blockchain of the nodes that receive the new block, so there will be two different blockchain at one point.
  2. What is a stale block?
    The block which was valid at one point in time but later ignored (dropped) as a different version of the blockchain was chosen.
  3. How do stale blocks occur?
    The other version(s) of blockchain was chosen instead of this one.
  4. Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?
    Because it may be the case that two or more versions of blockchains are competing and this one may be dropped eventually.
1 Like
#4162

does that mean that if a miner has low hash rate compared to other miners, it wont get ANY block rewards at all?.. on the contrary, btc can be mined by any individual with a small scale setupā€¦ but how then they receive the mining rewards? if the miner with the fastest hash rate always wins the block, small scale miners would never get their blocks accepted?..Also, is the transaction fee paid to all the miners or only to the ones who gets their block accepted?

#4163

Yes, mining is based on game theory, it is literally a game, and the winner takes it all. The players are aware of this and they play either to win or lose.

#4164

The winning miner claims a block reward by adding it as a first transaction on the block.

#4165

Only the winner gets the block reward and the transaction fee.

#4166

1. What happens in the bitcoin network when two miners solve a block at the same time?
the chain forks in 2 possible variants of the truth, one version of the truth will be chosen by the next miner that builds a block and the chain will continue with that version, making the other block invalid

2. What is a stale block?
a block that has been added to the chain but later dropped/removed because a different, longer version of the blockchain was accepted by the rest of the network.

3. How do stale blocks occur?
if 2 blocks have been mined at the same time a fork will appear, which ever block gets picked as the continuing link in the chain that becomes the valid block, making the other one(s) stale block(s)

4. Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?
this way there is confirmation that your transaction is part of the(a) block that has been chosen by the network as the real version of truth.

1 Like
#4167

  1. If two miners solve the nonce simultaneously, then both blocks proceed in the network until the next
    block is established that contains more POW emerges on the chain. Then the shorter POW block is dropped and the txā€™s are returned to the mempool.

  2. A stale block is a block that had to be dropped due to conflict resolutions in the protocol as described
    above. (in competing chains, the shorter block that contains less proof of work will be dropped)

  3. Stale blocks that were confirmed at one time by the network, but had to be discarded back to the mempool in order to prevent a disorderly blockchain that arises from competing chains.

  4. It is important to wait for about 6+ confirmations to ensure that your transaction will stay in permanently in the blockchain without any discarding issues.

1 Like
#4168
  1. What happens in the bitcoin network when two miners solve a block at the same time?

The block that gets to continue the valid chain will be the one that propagates its version of the blockchain across the most amount of nodes, receiving the 6 confirmations and having its block used to continue that blockchainā€™s height. The biggest chain wins as the chain being used across the Bitcoin network.

  1. What is a stale block?

Blocks that are successfully mined but not included on the valid chain due to it not having a followup block added to it.

  1. How do stale blocks occur?

They occur when the chain they wrote too hasnā€™t received the required 6 confirmations and not being extended further by other miners writing subsequent transaction to that chain but to the winning chain instead.

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

This allows the network and nodes to further mature after the block in question to further discourage and make it harder for a rogue attacker to exploit the network or attempt double spending.

1 Like
#4169
  1. What happens in the bitcoin network when two miners solve a block at the same time?

Both blocks get into the blockchain not being aware of the conflict. The chain will fork, but in the end one of them will soon be removed.

  1. What is a stale block?

The removed block from the blockchain.

  1. How do stale blocks occur?

When 2blocks get accepted by miners into the blockchain at the same time hence the one in the shorter chain will be dropped.

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

For the reason if blockchain forks with the same blocks, one will need to be removed. And We need at least 6 confirmation to make sure itā€™s not the stale block and our transaction will be invalid

1 Like
#4170

  1. What happens in the bitcoin network when two miners solve a block at the same time?
    Because only one chain (the longest) will win, there is a risk of the the shorter chain to be dropped and become a stale block

  2. What is a stale block?
    Orphaned blocks that were dropped because it did not make it to be the longest node to be accepted by the network

  3. How do stale blocks occur?
    When two blockchains that were completed almost at the same time but was not chosen the next miner to be incorporated into the new chain.

  4. Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?
    It will have more time to be confirmed more times therefore ensuring that the block is not dropped and become a stale block

1 Like
#4171
  1. The blockchain chooses to add the block with most PoW.
    2.A stale block occurs when a block in not added to the blockchain because the miners working on that block did solve it quicker than miners working on another block.
  2. When a competing block is solved quicker.
  3. Because the block your transaction is riding on may not be accepted by the blockchain
1 Like
#4172

Homework - Stale Blocks

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

Both blocks will be validly appended to the blockchain. As more blocks are added, the shorter chain is discarded and the transactions front the dropped blocks will be placed back in the mempool to be re-added to the (node-) acknowledged, longer version of the blockchain.

  1. What is a stale block?

A stake block or orphaned block is a block that has been dropped from the blockchain as a consequence of being part of a shorter version(/fork) of the propagated blockchain.

  1. How do stale blocks occur?

Stale blocks are made are blocks of transactions, validly appended to the blockchain, that are then later found to be part of the shorter fork of blockchain, and hence dropped, as the blockchain is propagated to other network nodes.

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

Any block can become orphaned and stale as a consequence of being part of a small fork of the blockchain. Hence it is practical and prudent to wait for multiple blocks to be added beyond the block which contains your transaction to be assured that it will not be returned to the mempool to be placed into a new block on the longer chain. 6 confirmations have been seen to be adequate as, at this time, it unlikely the blockchain would be required to drop that many blocks at once to correct its propagation of blocks.

1 Like
#4173
  1. What happens in the bitcoin network when two miners solve a block at the same time?
    2 different and valid versions of the truth are created and exist on the network with a 2 groups of nodes, one group with one version of the truth and the other group with another version of the group
  2. What is a stale block?
    A block of the version of the truth that is dropped because it was not part of the winning block created to resolve the 2 versions of the truth scenario
  3. How do stale blocks occur?
    They start with 2 new miners each guessing the nonce at the same time, creating their block, appending & propagating their version of the ledger to nearest set of nodes to their node.
  4. Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?
    A confirmed block may become stale or orphaned.
1 Like