Homework on Stale Blocks

Blockchain and Bitcoin 101
#3431

They split into two separate chains until one gets longer.

A stale block is a perfectly valid transaction that gets kicked off the chain because their not on the longest chain.

When one chain becomes longer, the transaction on the shorter chain becomes stale.

So that stale blocks do not add up and the network remains secure.

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#3432
  1. The subsequent blocks mined will form a longer chain and drop the competing block from the blockchain.
  2. Valid blocks that were in the blockchain at one time, but then got dropped because there was a larger version of the blockchain.
  3. Stale blocks typically occur due to competing miners completing a block simultaneously.
  4. To avoid different versions of the blockchain which results in stale blocks.
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#3433

The two blocks will be propagated through the network. Depends on the physical location some nodes will take block A as the truth and some others will take block B as the truth. Hence there will be two blocks floating around. Now comes miner C and will build his block on block B - then this is the longest blockchain and will survive. A will be dropped and goes back to the mempool.

A rejected block aka orphaned block or dropped block - in my example above block A.

Since there is many miners competing to be the fastest to solve the cryptographical puzzle. In case two miners solving the block exactly at the same time one must be dropped since another miner was building on the other block. Going back to mempool.

To avoid your block is staled and goes back to mempool. 6 blocks is the recommendation - since it will represent 6x10 mins = 1 hour.

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#3434

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

Both blocks get added and there are 2 versions of the blockchain circulating arround.

What is a stale block?

That is a valid block that gets dropped from the blockchain due to it not beeing in the longest version of it.

How do stale blocks occur?

They occur when the blocks get minned at the same time.

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

Because the block where the transaction is, might eventualy get dropped from the blockchain.

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#3435

  1. What happens in the bitcoin network when two miners solve a block at the same time?
    Both blocks will be propagated through the network.

  2. What is a stale block?
    A stale block is a block that is dropped

  3. How do stale blocks occur?
    When two blocks are created at the same time and are propagated simultaniously through the network there will be two versions of truth. It will be som until one of the miners blocks is chosen by another miner making a longer chain with its block. The shorter chain will then be dropped and the block which then is unvalid is called a stale block.

  4. Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?
    Because it minimizes the risk of your transaction being in a stale block and therefore unconfirmed again.

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#3436

There will be 2 different versions of the blockchain until another miner solves a block and adds it to one. This will then be the chain that is picked up by the network and the other block will have its transactions returned to the mempool.

A stale block is one that is solved at the same time as another block and is left unconfirmed.

When there are 2 versions of the blockchain and it gets left on the chain that isn’t accepted by the network.

It makes it less likely that your transaction will be on a stale block. After 6 confirmations the chain is very likely to be up to date and correct.

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#3437

1_ They are both added to the chain causing a split end, depending on the way their blocks spread through the network, two truths exist at the same time until one end of the chain is propagated upon.

2_ A stale block is the block that gets dropped from the split end, when the other end propagates. The tx go back into the mempool.

3_ uhm see above?

4_ To make sure your tx does not go for a swim in the mempool again because your block got stale.

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#3438
  1. Both of the blocks are valid, a temporary chain occurs; when new block gets added the longest chain “wins”, the other transactions get returned to the mempool
  2. A block that has been dropped from the chain
  3. This occurs when two miners produce valid blocks at similar times. The miner whose block is produced at a slower rate ends up with the orphaned block.
  4. It is important to wait for 6 confirmations so that the block is not dropped from the chain.
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#3439

1- Both blocks are valid but only one will stay on the blockchain while the other one will be dropped

2- A stale block is a block that was dropped from the blockchain

3- A stale block occurs when 2 miners create a block at similar times but only one is chosen by another miner to continue the chain.

4- To confirm that your block hasn’t been dropped from the chain.

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#3440

  1. What happens in the bitcoin network when two miners solve a block at the same time? Blockchain will split and there will be two valid versions of the reality. After the new block arrives the longest chain win and orphan block will be forgotten. Transactions from orphan blocks appear back in the mempool.

  2. What is a stale block? Stale block = Orphan block. Block hash is correct but block is not in the longest chain.

  3. How do stale blocks occur? When there are two miners who mine new blocks 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? Because even if a transaction has status confirmed it may happen that transaction is in the orphan blocks.

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#3441

There are to versions of “truth” at the same time. 3rd miner will conclude to which blockchain new block will be apended and as a result accepted by the network.
2.
Stale block is a block that got invalidated for example in a cas when the other bloc waas “chosen” becvasue it was longer and got accepted by the network.
3.
When to the other version of blockchain a new block is being appended and it gets longer thus accepted by the network.
4.6 blocks are required for the transaction to by validated, after this transaction is accepted and added to the blockchain or get back to the mempool

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#3442

  1. Both of the blocks will be created since they are both valid, but only the one that is continued on within the 10 minute period is going to be used. The other block will be dropped.

  2. A stale block is the block that was dropped due to having the shortest blockchain.

  3. Sale blocks occur because the next miner chose to create a block based off the other block that was created. The next block is created based on the previous block so if the blockchain is continued off of a block that is not yours and it ends up being longer, your block will become stale.

  4. It is important to wait for at least 6 confirmations to ensure that the transaction is not inside of the block that had become a stale block and had dropped.

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#3443

  1. The miner with the longer chain of work wins and the other is discarded.

  2. A stale block is one that has been dropped due to there being a longer chain of work.

  3. When 2 blocks are produced at the same time.

  4. Should wait for 6 confirmations incase of a stale block

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#3444
  1. Each block reaches out to the nodes closet to them and the network waits for confirmation to reach consensus. The longest chain wins.
  2. a valid block that was not the longest in the chain and is discarded.
  3. A block that is not the winner or chosen by the next miner for the next block so the block drops and the tx go back into the mempool
  4. it reduces the chances of nodes dropping off and becoming stale
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#3445
  1. Two versions of the truth are considered to be occurring at the same time. A 3rd miner on both chains will link themselves to their version of the truth. Only the chain with the longest PoW recorded will be selected and accepted by the network for subsequent blocks.

2)A block that gets dropped and its TXs are sent back to the mempool since it was on the chain version with the least PoW and not accepted as the TRUE chain.

  1. When there are two versions of the blockchain being propagated across the network and the chain that does not get accepted contains blocks with confirmed TXs in it. These blocks are considered stale or orphaned.

  2. with 6 confirmations the transaction is considered validated or permanent. This is because the odds of your block being a stale block after an hour has passed and the network has not accepted one version as the official truth is highly unlikely.

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#3446
  1. When 2 miners solve a block at the same time, valid blocks are spread to the nodes closest to that miner and work outward. It then rests on the next miner(s) to solve the following block(s) for the system to choose which spit has the most POW, to accept that original split.
  2. A stale block is a block that has been accepted to the blockchain but then is dropped do to another split being accepted as the truth.
  3. When 2 blocks are added to the chain at the same time, then one of those blocks are dropped for the other, this is when stale blocks occur.
  4. Because that block could potentially be dropped as a stale block.
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#3447

1.There are 2 versions of the truth.
2. It is a block that were drop for a new block
3. when miners choose another block, because it has a higher POW
4. to make sure the transaction is approved. If not, can be a orphan.

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#3448
  1. What happens in the bitcoin network when two miners solve a block at the same time ?

The miner who solve the next block can decide on which block he continues. The block which dont get picked by the miner get “destroyed” and the tx in this block will return to the mempool.

  1. What is a stale block?

The block which get dropped from the Blockchain.

  1. How do stale blocks occur?

Because 2 minders find a block at the same time and pick diffrent transactions. So the hash of the 2 blocks are diffrent.

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

After 6 confirmation u can be sure that your transaction is not part of a stale block.

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#3449
  1. What happens in the bitcoin network when two miners solve a block at the same time?
    -with the longest blockchain will win. and another block will sending back the tx to the mpool
  2. What is a stale block?
    -is the block that was in the blockchain but then dropped because another block was produce at the same time with longer chain
  3. How do stale blocks occur?
    -occur when 2 miner or more mine a valid block approx 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?
    -to avoid/ reduce the stale block occur
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#3450
  1. The blocks are propagated to the network. As new blocks are created by miners the longest chain will be accepted by the network and the shorter chain will be dropped.
  2. A stale block is a block that was dropped and the transactions in that block are returned to the mempool.
  3. A stale block is created when a block is successfully created but isn’t able to be propagated to enough of the network and another block created at the same time is built upon first, thus creating a longer chain, and this chain is accepted by the network.
  4. It is best practice to wait for 6 blocks to be confirmed in order to have confidence that the block has been accepted as the longest chain in the network and thus won’t be dropped.
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