Homework on Stale Blocks

Blockchain and Bitcoin 101
#4234

  1. The miner that has the longest chain gets accepted. The other block is considered stale and returned to the mempool.

  2. A stale block is a block that gets dropped as it is in the shortest chain of two blocks solved at the same time.

  3. Stale blocks occur because two miners solve a block at the same time. Nodes closest to the miners pick up their solutions and confirm them. The block that has the shortest chain cannot be added to the blockchain and is returned to the mempool.

  4. Just in case your transaction is in a block that might be dropped and added to the mempool. You should always wait for 6 confirmations outside of your block to make sure it doesn’t get dropped.

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#4235

  1. When two miners solve a block at the same time, both blocks will be placed a two different versions of the blockchains picked by nodes, however only one block will remain depending on the next mined block

  2. a stale block is one of the two blocks that will be dropped and not chosen by the miners to build on his next block

  3. Stale blocks occur when two miners mine a block at the exact same time

  4. It is important to wait in order not to be have our txn in a stale block which will get back into the mempool

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#4236

Q.1.What happens in the bitcoin network when two miners solve a block at the same time?
A.1. You will have blockchain splitting, all blocks are valid, since the other nodes
are not aware. Eventually the longest block will be completed based on most efficient miner

Q.2.What is a stale block?
A.2. Blocks that have dropped from a node and placed in the mempool

Q.3.How do stale blocks occur?
A.3.that are not being processed dueto another longer transaction chain

Q.4.Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?
A.4.To ensure that all information is propagated around the world to all nodes in the network

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#4237
  1. What happens in the bitcoin network when two miners solve a block at the same time?
    Both the blocks get appended to the previous block
  2. What is a stale block?
    A block which was appended to the previous block before being dropped from the blockchain
  3. How do stale blocks occur?
    If two blocks are appended to the previous block at the same time, there will be two versions of the blockchain created and propagating through the nodes. A following block will be appended to one of the two blocks, increasing that version of the chain’s proof of work. The verion of the chain with the most proof of work will be accepted, and the other version will be removed from the blockchain and its transactions returned to the mempool.
  4. Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?
    After being confirmed by only one block, there is a possibility that the block containing the transaction will be removed from the blockchain. Good practice is to wait for 6 confirmations to obtain certainty that a block will be accepted.
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#4238
  1. What happens in the bitcoin network when two miners solve a block at the same time?

Half the network would have a version of the truth and the other half of the network another version of the truth. So, when another miner requests which blockchain is correct and picks one of the two blocks based on the feedback. This would result in one of the blockchains now becoming longer than the competing block and the network will only accept the longest blockchain out of the two based on most proof of work and therefore the competing blockchain would be effectively dropped and all of its transactions returned to the mempool.

  1. What is a stale block?

Stale blocks are blocks that were in the blockchain at one time as a valid block but then got dropped because there was another version of the blockchain that was simply longer without those blocks in it.

  1. How do stale blocks occur?

If blocks are coming out at a faster rate than the 10-minute interval block time rule, then the block wouldn’t have enough time to propagate throughout the network before the new block comes out resulting in two blocks competing with each other and one of them might be dropped eventually producing a stale block.

  1. 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 six confirmations after your transaction to ensure that your transaction block is not dropped within the chain which would result in your transaction being incomplete and returned to the mempool.

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#4239
  1. If two miners solve a block at the same time both blocks will be linked to the blockchain. There will be a temporary fork. Eventually one chain will be longer, and the longest chain wins. The blocks on the shorter chain will be dropped.
  2. A stale block is a block that got dropped because there is another version of the blockchain that is longer.
  3. Stale blocks occur when two blocks are linked to the block chain at the same time creating a fork. The chain that is longest wins, so the blocks that are on the shorter chain are dropped. A valid block that gets dropped is called a stale block.
  4. It is important to wait for more than one block confirmation when sending and receiving a transaction because it is possible that your transaction is in a block that will be dropped. (Best practice is to wait for 6 block confirmations.)
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#4240
  1. What happens in the bitcoin network when two miners solve a block at the same time?
    Two different simultaneous versions of the blockchain, each with a different block, are propagated out over the network. When the next block is mined and attached to one of the two new blocks on the chain then that will be the enduring blockchain.
  2. What is a stale block?
    I stale block is an orphaned block that has not been built on by the miners and no longer included in the blockchain.
  3. How do stale blocks occur?
    When two different simultaneous versions of the blockchain, each with a different block, are propagated out over the network. The block that is not built on to propagate the blockchain, becomes a stale block and its transactions returned to the mempool.
  4. Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?
    To ensure that your transaction is not on a stale block that will be orphaned with its transactions sent back to the mempool. 6 confirmations ensures your transaction is permanently included in the blockchain.
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#4241
  1. The longest block will will and the other block will be dropped been called orphaned block.
  2. It’s an orphan block that lost the battle with a longer block where the longer block was accepted and approved and the stale block got dropped.
  3. When there is two different miners validate two versions of the true and the block with the longer chain will continue into the network causing the other block to be invalidated.
  4. To make sure your transaction don’t end up in a stale block making the transaction to be dropped from the chain.
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#4242

1.The block with the most accumulated computational work wins and the rejected version of the blockchain is discarded and will be returned to the mempool for miners to consider it again.

2.A block that was successfully mined but not included on the current longest blockchain, due to another block being added to the chain first.

  1. The rule of the longest chain wins. Multiple, competing chains get blocks added to them, they increase in length all while competing to become the longest. During this process the blocks on a shorter chain can get left behind, creating stale blocks.

  2. Not confirmed means occurrence of a stale block, the block is then returned to the mempool for miners to consider it again.

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#4243
  1. The chain splits into two ends, the longer chain wins and the other chain is considered stale. All transactions are then returned to the mempool.
  2. A stale block is a block that has been dropped due to a fork.
  3. Stale blocks occur when two miners mine a valid block at the same time and drop the shorter chain.
    4.It is important to wait for more than one block to be confirmed because you want to avoid a stale or orphan block. The recommendation is to wait for 6 confirmations
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#4244
  1. What happens in the bitcoin network when two miners solve a block at the same time?
  • There will be 2 next blocks in the blockchain. They will whait to see what block the next one will continue on. the one with no next block, will be rejected and the transactions will go back to the mempool.
  1. What is a stale block?
  • A block with no next block
  1. How do stale blocks occur?
  • when a miner continues the blockchan on another block mined 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? you have to know for sure, if the block with your transaction not is a stale block.
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#4245

  1. What happens in the bitcoin network when two miners solve a block at the same time?
    -The block with the longest chain will win and the losing block will be dropped.

  2. What is a stale block?
    -The blocks that are dropped because there is a longer form of the blockchain. They are valid but not the longest in the blockchain.

  3. How do stale blocks occur?
    -Blocks are valid but then dropped because the blockchain continued on another block.

  1. Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?
    -Minimize issue with stale blocks and give the blocks time to propagate in the network.
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#4246

When two Miners solver a Block at the same time, the influence will rely on the rate the blocks spread across the nodes and miners, which could generate two versions of the same blockchain. A influential factor will be over which Block the miners continue appending blocks. After that the blockchain will see which continuation is the longest, and it will be used the other block will be forgotten. To this forgotten block, we´ll call it “Stale Block”, and it will be returned to the “Mempool”. This is the reason why during the action of moving your “Bitcoin” you have to wait at least 6 “confirmations”. A “Confirmation” is when a new block is appended to the blockchain, so if you need “6 confirmations”, you´ll need 6 new blocks more for your transaction to be safe and eliminate the possibility where the block becomes “Stale”.

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#4247

  1. If 2 miners solve a block at the same time, eventually one will win out when other blocks are created on top of the “winning” block. The losing block will be discarded (stale block) and the transactions will be returned to the mempool.

  2. A stale block was a legitimate block on the chain, but one that was created at the same time as another block. The stale block lost out to the other block and was then discarded.

  3. A stale block is one that was created at the same time as another block but eventually is discarded because the chain continued to be built on that other block

  4. It’s important to wait for 6 confirmations so that you can be sure that your transaction was not part of a stale block

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#4248

  1. When two miners solve a block at the same time, both blocks are valid for a period of time.

  2. A stale block is a “discarded” block that wasn’t extended by the network because another block with the same height was chosen first.

  3. Stale blocks occur when two blocks with the same height are broadcasted to the network and different nodes located in geographically different places receive different versions of the blockchain. Until the the next block is added to the blockchain, both of those versions are correct, but one will become stale, and discarded while the transactions inside go back to the mempool.

  4. It’s important to wait for more than one block to be confirmed to reduce the risk of a stale block.

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#4249

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

Both blocks are added to the blockchain.

2. What is a stale block?

When two blocks are added simultaneously as the most recent blocks to the blockchain whichever of those blocks gets another block added next to it will be the correct version of the blockchain since the longest chain of blocks are accepted by the network. The other of the simultaneously confirmed blocks will be discarded from the block chain and its transactions will be put back into the mempool. This “discarded” block is what is known as a stale block.

3. How do stale blocks occur?

The concept of stale blocks starts to occur when two mining nodes confirm their own blocks of transactions at the same time and both of their blocks are added as the next block in the blockchain, essentially forming two blockchains.

Whichever of these blockchains gets another block added to it first will immediately be accepted as the valid blockchain (since the longest blockchain is accepted as the valid blockchain) and the other block will be discarded, becoming a stale block.

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 six confirmations or six more blocks to be added to the blockchain after the block containing your transaction. The reason for this is to avoid as much as possible the above problem of stale blocks from occurring.

The 10 minute rule (that a single block should be added after approximately 10 minutes) is also built into the bitcoin blockchain to avoid this problem of stale blocks.

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#4250

  1. The chain splits into 2 and eventually the longest chain is accepted and the other chain is dropped.

  2. It is the blocked that gets dropped from the chain

  3. Stale blocks occur when different miners add a new block to the chain at the same time splitting the chain. Stale blocks occur when blocks are dropped from the chain by nodes when all nodes are updated to the new chain

  4. It is important so that validated transactions do not end up as stale blocks

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#4251

  1. The block followed by 6 confirmations(6blocks) and is the longest block by the end of the 10min will be the block to continue to exist on the block chain. Each gossip to the network of nodes, the nodes closest to each miner pick up respective solutions. Network must wait for a confirmation to settle consensus.

  2. A stale block is a block which was present on the blockchain but was removed due to no longer being the longest block and other miners having built more blocks on another block-chain.

  3. When other miners find the nonce +previous hash+tx list faster on the other blocks leading to only 1 blockchain being the longest and the shorter blockchain will become stale blocks. Valid block was not in the longest chain.

  4. Because a miner producing a block at the same time as another miner can be followed by two other miners producing a block on each block, thus not having guarrenteed permanence unless one of the blocks become longer and that block will prevail. Greatly reduces the odds of becoming stale.

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#4252

  1. What happens in the bitcoin network when two miners solve a block at the same time? The block with the longest chains wins and the other block (now stale) is dropped (and its transactions placed back in the Mempool).

  2. What is a stale block? A block that gets dropped from the Blockchain (typically because a competing block was confirmed).

  3. How do stale blocks occur? When two blocks are validated at the same time, and the other block is kept (longest chain).

  4. Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction? In case the scenario presented above comes about (two competing blocks are validated simultaneously). Six confirmations virtually ensures that the block in question is part of the longest/winning chain.

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#4253

  1. when two miners happen to find their respective nonces (i guess the nonces must be different if their transaction lists are different) yielding hashes under target and submit them simultaneously, then their newly appended blockchain is propagated to all those nearby nodes who accept it, but neither new chain has earned consensus as the longest chain quite yet because the blocks are both valid and thus the chain length for both is equal… UNTIL one block is “confirmed” implicitly by virtue of its chain (and NOT the other’s chain) being appended to by the NEXT block (or at least the next handful of blocks, i.e. there’s a subsequent race for whose blockchain will earn consensus)…

  2. a stale block is a block that used to exist in the chain but no longer does.

  3. stale blocks happen when one version of the blockchain was removed due to another being lengthened before it was, i.e. the blocks are made stale when newer blocks added to the chain ignore them in favor of another (“longer”) chain’s blocks that causes them to disappear upon its propagation to every node in the database

  4. sometimes enough blocks are in question (i.e. enough versions of the truth are out there waiting for their chain to be lengthened) that ; thus it’s important to wait for more than one block to be confirmed to “know” that the consensus is established with respect to the history of transactions, i.e. to be sure the transactions can not be undone later (maliciously or not).

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