Homework on Stale Blocks

Blockchain and Bitcoin 101
#4414

Answer 1 - The block with longer blockchain or larger acceptance will be added into blockchain and other block will be dropped

Answer 2 - A Valid dropped block is also called as Stale Block

Answer 3 - Once the valid block is dropped from adding into blockchain due to lower acceptance or shorter blockchain forrward to it then it becomes a stale block

Answer 4 - To ensure propogation of confirmed block to nodes in the network

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#4415

  1. What happens in the bitcoin network when two miners solve a block at the same time?
    The chain splits. Some nodes have accepted one of the blocks some have the other one. The block that continues the blockchain wins.

  2. What is a stale block?
    An orphaned block. A completely valid block that got dropped of the blockchain.

  3. How do stale blocks occur?
    When the chain splits and different nodes have different versions of the blockchain one of the versions continues the blockchain and the other completely valid block gets ditched. The last one is 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 your tx might have gotten into the stale block therefore returned to the mempool

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#4416
  1. Two version of a blockchain appear, two chains, which are broadcasted to the network. Later, only the longest chain will survive.
  2. Stale block is a block, which is mined correctly, but not included in the blockchain due to not being in the longest chain after temporary fork.
  3. When two blocks were mined simultaneously, so they are added to the blockchain parallelly (only one block will survive though).
  4. Because txs can go into stale blocks and might not be included in the chain immediately. Therefore, six confirmations are enough to ensure the validity.
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#4417

Continuing the discussion from Homework on Stale Blocks:

  1. What happens in the bitcoin network when two miners solve a block at the same time?
    Two different blockchains will exist and the one with the longer chain will become the truth and other one will be dropped even though they are both valid blocks.
  2. What is a stale block?
    Block that is valid and got dropped due to other longer blockchain existence.
    That block than gets back to the mempool.
  3. How do stale blocks occur?
    Where multiple miners compete and they create their own version of truth.
  4. Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?
    Just to be sure your block doesn’t get dropped.
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#4418

1- the chain splits in 2
2- after a chain split, the next block will be added to one of the chains. the other chain will have a stale block, this block will be dropped and the transactions recycled as the other chain wins due to the proof of work on it.
3- Stale blocks happen when the difficulty is too low and new blocks are mined faster than it takes for them to propogate across the network, so difficulty is adjusted to keep the blocktime close to 10 mins
4- Wait for 6 confirmation (or 6 new blockk to be added to the one with your transaction), this will greatly improve your chances of not having your transaction part of a stale block and so failing eventually.

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#4419

  1. A fork is created.

  2. A stale block is a block that has been discarded by the system.

  3. They are created when there’s been a fork resulting in the system having to choose between two blocks, and the system chose the other.

  4. There’s always a risk that the block with your transaction in it gets discarded, and the more subsequent blocks there are the lower that risk is.

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#4420
  1. What happens in the bitcoin network when two miners solve a block at the same time?
    The network will choose the longest chain, all other blocks will be dropped and transactions will be returned to mempool.
  2. What is a stale block?
    A stale block is a block that were in the blockchain but got dropped.
  3. How do stale blocks occur?
    The next miner choose another block that is coming out at approximately the same time.
  4. Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?
    It is important that you make sure your block won’t get dropped.
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#4421
  1. What happens in the bitcoin network when two miners solve a block at the same time?

The both get added to a chain with the longer proof of work chain winning and the other block being dropped with transactions being released back into the Mempool.

  1. What is a stale block?

A stale block is a block that is dropped from the blockchain as the network chose another block that was added to the longer chain.

  1. How do stale blocks occur?

When a block is validated at the same time as another, but the blockchain carries on on another chain. The block that is then dropped from the shorter chain is considered stale.

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

As the block that your transaction is in could still be dropped if more confirmations aren’t given.

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#4422
  1. Two versions of the truth (valid chains) may exist in different nodes for a short time until one chain is longer and the shorter chain gets dropped
  2. It’s the last block on the shorter discontinued chain
  3. If another version of the chain with valid blocks is longer then the shorter one may go stale
  4. Waiting may confirm that your transaction was not be invalidated by its block becoming stale
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#4423
  1. What happens in the bitcoin network when two miners solve a block at the same time?

Some miners receive one block and others receive the other one, which means there will be two versions of the blockchain that are correct

  1. What is a stale block?

A stale block is a block that was in the blockchain at a given time but was then dropped

  1. How do stale blocks occur?

When there are two versions of the blockchain active, the next miner to append a block will do so in one of the two blockchains, meaning that the blockchain that the miner chose will now be longer that the other one, so the other blockchain will be discarted, resulting on the droppage of the appended block and all of its transactions will return to the mempool

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

To ensure your transaction isn’t on a block that might be dropped

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#4424
  1. When two miners solve a block at the same time, each creates their own timeline of the blockchain. They spread their copy of the blockchain to different nodes.
  2. A stale block is a block that has been dropped from the blockchain. All of its transactions have returned to the mempool.
  3. Stale blocks occur when a chain in the blockchain is dropped, because another version of the blockchain was chosen as the longest chain.
  4. Its important for more than one block to be confirmed because if you rushed it before confirmation, the block could become stale and be dropped. The transation would be furthur delayed in the mempool and the transaction woud take even longer. Its best to wait for 6 blocks after your block before confirming transaction.
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#4425

Good morning everyone!

  1. When two miners solve a block at the same time, a third miner will end up choosing one and making another block based on that block. The network will then choose the longest (most proof of work) chain.
  2. The block that was spit out or not chosen will become stale.
  3. Stale blocks are those that were once approved but then spit out over another in the same place in line.
  4. It is important to wait for more than one block to be confirmed when sending or receiving to ensure that the entire consensus of the network agree to keep the block that has your transactions on it.
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#4426

  1. They compete with eachother until the next blocks connects to one of them. Then th shorter chain get droped called stale block or ovphaned.

  2. A dropped block that lost the competition.

  3. When two valid blocks get mined and a fork is resolves with a longer chain.

  4. two make sure Its the longes chain in the blockchain and not get droped.

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#4427

1. What happens in the bitcoin network when two miners solve a block at the same time?
Both miners will start broadcasting their completed blocks to other nodes, and other miners will start mining on top of whichever node they have access to; eventually 6 blocks will be confirmed after one of these completed blocks first, and that chain (the longest of the two) will be accepted as the true blockchain and the unaccepted chain will send all the transactions back to the mempool.

2. What is a stale block?
A stale block is a mined block that doesn’t get chosen as the “longest chain” and no longer is the source of truth on the blockchain. When this happens, all transactions in the stale block will be sent back to the mempool.

3. How do stale blocks occur?
Stale blocks happen when the blockchain forks from 2+ miners mining a block at the exact same time, and then whichever of the forked chains doesn’t get accepted as the source of truth will become stale blocks.

4. Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?
If I understand this question correctly, waiting for more than 1 block to be confirmed (up to 6 confirmations?) will help keep the blockchain as a single chain by preventing forks from happening (when 2+ miners mine a block at the exact same time); every 10 minutes all nodes will sync with each other, and will get the longest chain of newly mined and confirmed blocks.

Thanks to @fsvolt answer to this question, I understand what’s being asked (thank you!)

The reason why it’s important to confirm more than 1 block before notifying a buyer/seller of the sent or received transaction is to ensure that the transaction isn’t part of an orphaned (or stale) block. Waiting up to 6 blocks (1 hour worth of POW) seems to be the standard for the most reliable confirmation, though it’s very rare for a transaction confirmation to take that long (in my own experience, though I have had it happen once).

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#4428

  1. In this situation, 2 different chains are created. when miner append a new block to one of the versions, it now have the longest version of the blockchain, so all other nodes accept it as the true blockchain and the other block become a stale block.

  2. a stale block is a block that used to be on the blockchain but got dropped because there was a longer version with different block.

  3. when a different version of the blockchain that doesn’t include this certain block, got accepted, this block will be dropped and become stale.

  4. To prevent a stale block form being created, if it happens, the transactions will not be include in the blockchain and will not get executed. by waiting for more blocks to be confirmed you can be sure that the chain is final and won’t change.

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#4429

1. What happens in the bitcoin network when two miners solve a block at the same time?
The block that has a miner solve a block on top of theirs first, will become the longest chain and thus being appended as the true blockchain. The transactions of the dropped block will return to the Mempool

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

3. How do stale blocks occur?
This occurs when two miners solve the puzzle for the block around the same time and two different versions of the blockchain exists, with one eventually losing to the other and 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?
To allow time for the new block to be spread around the network to ensure that the block is truly confirmed and that different versions of the blockchain don’t exist. Basically to ensure that the block the transaction is in does not become stale, and added back to the Mempool.

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#4430

  1. What happens in the bitcoin network when two miners solve a block at the same time?
    The Bitcoin network now has 2 Miners – e.g., YELLOW Block & BLUE Block – that each have UNCONFIRMED Transactions, but are each valid Blocks. This creates a network with more than 1 truth, as the YELLOW & BLUE Blocks are broadcasting to other Nodes in the network. Depending on which Node you communicate with, the circumstances may be different depending upon which recent Block information the Node received (YELLOW or BLUE).

  2. What is a stale block?
    A STALE Block (aka “ORPHANED” Block) is a valid Block with UNCONFIRMED Transaction that becomes the Block that is rejected by the Blockchain network when 2 Miners solve a Block at the same time. The UNCONFIRMED transactions from this STALE Block are returned to the Mempool.

  3. How do stale blocks occur?
    The Bitcoin network has 2 Miners that each have UNCONFIRMED Transactions, but are each valid Blocks. This creates a network with more than 1 truth, as the 2 Blocks are broadcasting to other Nodes in the network.
    It’s all about which Block will a Miner choose, which Block will the network continue mining, and which Block will be removed (it’s Transactions will be returned to the Mempool).
    The longest chain link will determine which of the Blocks in UNCONFIRMED status will be appended to the Blockchain (e.g., Blue and Yellow Blocks in UNCONFIRMED status, but Green Block chooses Yellow Block and the Purple Block chooses the Green Block, so the network collectively determines that the new Yellow/Green/Purple Blocks is a longer chain link than just the Blue Block, so the network rejects the Blue “STALE” Block).

  4. Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?
    The best practice is to wait for 6 CONFIRMATIONS of New Blocks (6 CONFIRMATIONS are the Blocks that choose the UNCONFIRMED Block that is based upon the longest chain link (e.g., Yellow Block) that will ultimately have its Block appended to the Blockchain.
    If a Miner (called the Beige Block) chooses a Block that will end up being the STALE (or ORPHANED) Block, then the Beige Block risks also being rejected and becoming a STALE Block.

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#4431
  1. What happens in the bitcoin network when two miners solve a block at the same time?
  • The miners propagate their block to the next nodes and they add that block to their copy of the blockchain. So, different branches of the blockchain have been created.
  1. What is a stale block?
  • A stale block is a block wich has been added to the blockchain at one time but later on has been dropped due to that copy of the blockchain has been rejected by the network (as a longer version of the blockchain exists in the network too).
  1. How do stale blocks occur?
  • Stale blocks occur based on the matter that, at one time, one copy of the blockchain with the most validated blocks (longest blockchain) will be chosen by the network to be the only truth and all other existing copes will be dropped. Thus, all validated blocks being added to the copies of the blockchain at the time the splitting of the blockchain occur, will become obsolete and all transactions go back to the mempool. Those dropped blocks are the so called stale blocks.
  1. Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?
  • As transactions might be dropped due to they might be part of a stale block, it is important to wait for confirmation more than one block. After a certain time (usually one hour after the block has been added to the blockchain), the network should have been synchronized and all will have consensus on the validity of that block.
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#4432

1.The blockchain network forks when two miners solve a block at the same time

  1. A stale block is a block that was once a part of a valid blockchain, but later was dropped due to it not being part of the side of the fork which eventually became the longest, hence most valid

  2. Stale blocks occur by being dropped from the side of the fork that is least valid (shortest)

4.It is important to wait more than one block to be confirmed when sending or receiving a transaction to make sure that the block in which your transaction was approved doesn’t end up being a stale block

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#4433
  1. When two concurrent blocks are submitted to the blockchain they create two branches of the blockchain and remain as such until there are six subsequent blocks added to each branch… and the longest branch of the two is retained and officially appended to the blockchain while the shorter of the two is discarded and any of the transactions contained therein are returned to the mempool.
  2. A stale block or an orphaned block is the shorter branch (of blocks) that is discarded as per (1) above.
  3. A stale block occurs when one of the two branches (of blocks) as described in (1) above is in fact discarded while the longer branch (of blocks) is appended.
  4. As there are timing differences inherent with propagation emanating from different parts of the world it takes time for concurrent branches (of blocks) to become evident across the entire blockchain… thus having the need for six blocks in any one branch of blocks provides sufficient time for the branch of blocks to become sufficiently evident across the network such that a winning (ie longer branch of blocks) can be assured.
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