Homework on Stale Blocks

Blockchain and Bitcoin 101
#3751

  1. One of the two blocks will end up with a longer chain length turn out and will be propagated, leaving the other block stale and its transactions will return to the mempool.

  2. A block that was at one point apart of the blockchain, however ended up discarded.

  3. when two miners produce a valid block only one of them will be propagated into the blockchain, leaving the other discarded and stale.

  4. To ensure the block containing ones transaction with not be rejected.

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#3752

  1. What happens in the bitcoin network when two miners solve a block at the same time?
    The one that mines the most blacks in terms of proof of work wins and the other’s blocks get dropped.

  2. What is a stale block?
    This is a dropped or orphaned block from a chain that did not get accepted by the network.

  3. How do stale blocks occur?
    If two miners mine the same block at the same time, eventually only one of those chains will succeed, while the other’s will fail to become validated by he network. those blocks will be considered stale blocks.

  4. Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?
    Without a 10 minute block time, blocks can go stale or be orphaned. If blocks are produced too quickly, it would not be enough time for the network to globally synchronize. The 10 minute limit enables enough time for 6 confirmation to ensure that there are no collisions.

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#3753

1: Two versions of the blockchain are created, resulting in a temporary fork.

2:A stale block is a block that has been removed from the blockchain.

3: Stale blocks occur after two miners solve a block at the same time. Once the longer blockchain is accepted as the official blockchain, the other version of the blockchain removes their now unnaccepted block.

4: To make sure that the block your transaction was in is not removed from the network.

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#3754

1- Both blocks are put into their corresponding chain and the chain that ends up the longest becomes the correct chain.
2- The blocks that were send to their corresponding chain but didn’t become the final block due to the length of the chain.
3- these happen when the longer chain is resoled and the block of the shorter chain becomes the stale.
4- Confirmation of 6 happens to to ensure the correct block gets dropped.

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#3755
  1. The two blocks will be added to the network but only the one with the longest chain of following blocks will survive.
  2. It is the block who got rejected and put back in the mempool
  3. When miners make a block at the same time
  4. So the chances will be higher that your blocks will be added to the network
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#3756

1.) When two miners solve a block at exactly the same time, both blocks begin propagating across the network, creating two different versions of the blockchain. Both blocks are valid - they have nonces that, when hashed with the rest of the block data, are below the target threshold, and they begin to propagate to the nearest nodes. This creates two separate blockchains - one with miner A’s block and another with miner B’s. Eventually there will be another miner (miner C) that will also try to append it’s new block to the blockchain. If miner C bases their new block on miner B’s version of the blockchain, it will cause miner B’s version to be longer than miner A’s. In this case, the network will accept the longest blockchain version (not necessarily the one with the most blocks, but the one with the most PoW).

2.) When this happens, we have what is called a stale block. The network will drop block A (the block with the least PoW), and return all the transactions it contains to the mempool for a miner to pick up again in another block.

3.) Stale blocks occur when the network drops a block due to 2 miners solving a block at exactly the same time.

4.) It is important to wait for more than one block to be confirmed when sending or receiving a transaction, because in the case that a block gets dropped (stale block) and your transaction was in that block, you’ll have to wait for a miner to pick it up again before it’s confirmed. Best practice is wait for 6 confirmations to make sure your transaction is fully confirmed. After 6 confirmations, you can be pretty certain that your transaction is a permanent part of the blockchain and can no longer be dropped or susceptible to double-spending attacks.

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#3757

  1. What happens in the bitcoin network when two miners solve a block at the same time?
    There will temporarily be two blocks connected to the previous block until the following block chooses which one of the two blocks it will ad on to. The transactions on the non-selected block return to mempool

  2. What is a stale block?
    A block that was temporarily on the chain but was not continued by following blocks and subsequently removed from the chain

  3. How do stale blocks occur?
    After two blocks have been simultaneously mined, the network will drop the block that ceases to be built upon.

  4. Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?
    To ensure that the transaction was not on a stale or orphaned block

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#3758

Each new block is a confirmation, which means a 6 confirmations take about an hour. :slight_smile:

#3759
  1. when two miners solve a block at the same time the next block we a two different blockchains.

2.A stale block is a block that was part of the blockchain but is being sent back to the mempool because a more difficult block was added to the block that was mined at the same time.

3.When two blocks with similar properties are added at the same time.

4.Because the global network is still confirming blocks after the one you mined so yours can be sent back to the mempool if your block was not chosen.

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#3760

  1. When 2 miners solve a block at the same time, both versions of the chain will propagate throughout the network till the next block (10 mins later) and the version that the next miner uses as the base will continue as it is having the bigger chain length.

  2. Stale block is the block that is not propagated in my example to answer of Q1. It is the block that gets dropped due to the other competing chain getting added onto.

  3. Answer is in Q1 &2

  4. There can be multiple versions of the chain running and this would be resolved after 1-2 additional blocks (best case is 6 blocks) being added to ensure that your transaction is so far back into the history that it will not be dropped.

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#3761

  1. What happens in the bitcoin network when two miners solve a block at the same time?
    Two different versions of the blockchain will be propagated till the network has choosen one over the other.

  2. What is a stale block?
    A block that has been dropped from the blockchain and returned to the mempool.

  3. How do stale blocks occur?
    When two blocks are created 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 make sure your transaction becomes part of the accepted version of the blockchain and not returned to the mempool.

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#3762
  1. The chain splits into two chains, the longest chain will win and all the TX of the other chain will go into the mempool.
    2.The block of the shortest chain after a fork and then it will be moved to the mempool.
  2. It occurs after a fork, it’s the block with the shortest chain.
  3. It is important to wait for at least 6 confirmations. The more confirmations the longer the block-chain length which means it can be the one accepted by the miners as the better version of truth.
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#3763

  1. When two miners solve a block at the same time, both of their blocks are added to the one previous block, creating 2 “branches” of the chain.

  2. A stale block is a block that gets disconnected from the blockchain after it has been previously attached to a block. The transactions within it are returned to the mempool.

  3. Stale blocks occur when the blockchain sees a longer chain and rejects the other blocks from the “other branch” of the chain. These rejected blocks are the stale blocks.

  4. This is just to ensure that your transaction will not go to a stale block. Waiting for 6 or more confirmations would assure you that your transaction will probably not end up in a stale block.

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#3764

  1. When two minors solve a block at the same time, then their blocks compete to see who will not get dropped. There will be two valid versions of the blockchain. Some nodes will have one version and other nodes will have the other version. In the end, only one true version will be accepted by the entire network and that is the longer blockchain with the most POW.

  2. A stale block is a block that was dropped by nodes because there was a longer blockchain that did not have that block in it. The transactions of a stale block go back to the mempool.

  3. Stale blocks occur when another version of the blockchain beat the version where the stale block was in. The entire network dropped the stale block because the longer version of the blockchain did not have it.

  4. It is important to wait for 6 blocks to be confirmed so that you officially know that your tx’s block will not get dropped and will stay. There is no way it will get dropped after 6 more confirmed blocks after it.

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#3765

  1. When 2 miners solve a block at the same time, and both valid, each work with surrounding nodes within the network closest continue the processing to adding the next block to the blockchain. Each chain must wait for consensus within usually10 minutes. Best practices prefer 6 confirmations during consensus. The longest chain wins while the other chain is dropped and returns to the mempool. If a third miner adds their block of work to one of the 2 chains and becomes the longest chain within the time frame, that miners block added to the chain becomes the longest chain then that is the chosen block to the blockchain. Still the lesser miners block is dropped (called a stale block) and returns to mempool.

  2. Dropped blocks that do not make the next block status become “stale” blocks and return to mempool. May be called “orphan blocks.”

  3. The work of mining blocks on blockchain is highly competitive with skills and timely work important to successful mining and recouping of expenditures of electricity and computer time. Solving the math and physics of hashes to make a new hash to add to the block by following the rules within approximately 10 minutes may create the next new block on the chain. However, if another miner arrives with an equally valid block to be added, the longest block is chosen to be the new block. The block that did not quite make to mark perhaps on time is dropped and becomes “stale.” The miner may try again for a different problem to solve.

  4. Resolution when there is so much activity and energy from computer nodes, miner nodes and possible lack of clarity yet in establishing the next new block to be added to the chain “best practices” allow time to settle consensus and what has been determined is approximately 10 minutes (a new block every 10 minutes) in the event that another miner would have the longest validated chain. Best practices allow for accuracy and security for the Network, and reduces issues that may arise and having to send too many blocks to mempool.

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#3766
  1. The miner who gets the first block attaches (longer chain) will win.
  2. Its a block that was in the blockchain but was dropped.
  3. When two blocks from different miners was i the blockchain for a while and then one of them is dropped beacause the other block got a longer blockchain.
  4. Beacause your transaction ca go back to mempool if your block is dropped.
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#3767

  1. You get two separate versions of the blockchain, each with a different last block

  2. A stale block is a dropped last block of the shortest blockchain, that is the blockchain that is not accepted because the largest blockchain will be accepted as the truth.

  3. When miners complete mining blocks at exactly the same time you’ll get multiple versions of the blockchain. The longest blockchain will survive, so when a new block is added to one of the blockchain versions, that one will be regarded as the truth. The other blockchains will drop the last mined block.

  4. Because the transaction can be in a block that will be dropped. When multiple blocks are being confirmed you know that this is the right version of the blockchain

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#3769

  • What happens in the bitcoin network when two miners solve a block at the same time? Both of the blocks become recognized as valid, and thus both versions of the truth exist simultaneously. At some point, the succeeding miners will then append to one of the versions, and the longest chain will be recognized by the network. The transactions from the other version that was not appended on will be sent back to the mempool to be added to the prevailing chain. Basically, the miner following this event will choose which one is appended, as the proof of work process inherently syncs itself to the accepted version of the truth (by the most miners).

  • What is a stale block? A block by which was created at the moment in time where two miners solved the hash function at the exact same time. The ‘orphaned’ or ‘stale’ block is the one that is not accepted onto the longest block chain, and whose transactions will be released back into the mempool, to be confirmed by the dominating block.

  • How do stale blocks occur? When the miner immediately following this event (the one where two miners solve the hash at the exact same time), appends to one of the two created versions of the block.

  • Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction? Because only the longest chain will be recognized by the network, and will thus prevail as the ‘accepted’ version of the truth. The accepted number is 6 confirmations following the split.

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#3770

  1. What happens in the bitcoin newtwork when two miners solve a block at the same time?
    There will be two notions of the truth circulating. The two blocks will be competing with one another to be added to the blockchain. The blockchain will accept the longest chain of blocks with the most difficult POW.

  2. What is a stale block?
    A stale block is the other competing block that was not accepted by the blockchain.

  3. How do stale blocks occur?
    When two blocks are competing to be added to the blockchain the nodes do not see the blocks on their ledgers yet. Only one chain of blocks can be added and the other will be dropped and transactions of the dropped stale block will be returned to mempool.

  4. Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?
    It is better to wait for at least 6 blocks to be added in front of yours to avoid the risk of your block to be dropped. If your work is dropped then all your transactions will be returned to the mempool.

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#3771

  1. The longest chain stays and the forked shorter chain will be droped, the blocks there will be stale, transactions inside will get back to the mempool.

  2. It was droped out of the blockchain, so it does not function within.

  3. It occurs, when multiple blocks are created within the same time and now have the same truth, the longer chain will be approved through additional blocks on that fork and the blocks outside will become stale.

  4. Because, you want the fastes way for your transaction, if you choose the wrong block your transaction gets back to the mempool und as to be picked by a miner again.

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