Homework on Stale Blocks

[Dimski45]

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

The block that is the longest will win over the shorter one, which will be orphaned or stale.
This returns to a mempool.

What is a stale block?

A block which was dropped because a block of a longer chain was produced at the same time and accepted over it.

How do stale blocks occur?

Whenever blockchain validates the block but accepts another block over it.

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

Because it can become stale. You should wait for 6 confirmations.

[frankiewalters]

Hey! Thanks for the feedback, appreciate it!!!

[BrianP]

1. Both blocks are considered valid until the next block on one of them is solved.
2. A stale block is one that gets tossed because another block has gotten built on first. The other block has more proof of work.
3. Stale blocks occur when 2 blocks are solved at the same time and one gets another block added to it first.
4. It is important to wait 6 blocks to give the network time to distribute the data worldwide.

[andrequintino]

1. What happens in the bitcoin network when two miners solve a block at the same time?
   When two miners solve a block at the same time can occur that some nodes received one block and the other nodes received the other block. This event split the blockchain network in two different networks, two versions of the truth and only when one of this two networks get more largest than the other, the largest one stays the only truth and the only network. The different transactions in the rejected network return to the mempool.

2. What is a stale block?
   Is a block that was rejected by the nodes because it doesn’t belong to the largest network.

3. How do stale blocks occur?
   A stale block occurs when exist two different versions of the blockchain network and one of these versions get largest than the other.

4. Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?
   Because if this transaction is present in a block that later became a stale block, this transaction return to the mempool and is no longer confirmed. The recommended way is wait for six confirmed blocks.

[CryptoXyz]

1. Initially there will be 2 versions of the truth that depends on the nodes closest to the miners that solved a block at the same time. Eventually, a new miner will mine on either of the newly added blocks and attach the mined block to either of the 2, which would lead to another blockchain having a longer Proof-of-Work which then the Network chooses to be true. Therefore, there will only be 1 version of the truth in the near future. The block that gets disregarded will have its transactions back to the Mempool.

2. A stale block is a block that has spent some time in the blockchain but is disregarded because of having a shorter Proof-of-work from a different block that was initially mined at the same time.

3. A stale block occurs when 2 blocks are mined at the same time and one blockchain from either of the blocks will have longer Proof-of-Work and thus the 1 version of truth that is accepted by the Network. The other blocks that connected to the losing block, including the losing block itself are disregarded from the blockchain and are called Stale blocks.

4. In practice it is recommended to wait for 6 blocks because there may be some blocks that are mined at the same time as your block was mined. Confirmation from other miners that mine from your block will increase your chances to be the blockchain with longer Proof-of-Work thus validating your version to be the One Universal Truth in the Network

[CornArtist]

1. The one with the longest blockchain gets accepted, and the block gets orphaned and the transactions are dropped back into the mempool.

2. A stale block is a block that was dropped as part of being in the shorter blockchain.

3. When Miner A mines this block, and Miner B who did not mine this block, had the longer chain and got accepted into the network. Hence the block that Miner A mined became a stale block.

4. To make sure your transaction is confirmed and would not become a stale block as more blocks are being built after it.

[Rui_Fernandes]

1. What happens in the bitcoin network when two miners solve a block at the same time?
   When two miners solve a block at the same we have two different truths, therefore creating a split in the blockchain.
   The network will only accept the link with the longest connectivity, so the other version is droped and the transactions list that fill that block will return do the mempool.
2. What is a stale block?
   Is a block that will be rejected by the network because it has a shorter connectivity.
3. How do stale blocks occur?
   When we have two versions, or blocks of truth and one of them is rejected by the network.
4. Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?
   Because the transaction could be in a orphaned block, making it a not confirmed.
   Only after 6 blocks the transaction will be confirmed.

[Eric_Roberts]

1. When two miners solve a block at the same time in the bitcoin network, nodes will replicate whichever block they detect first, thereby creating two competing blockchains. Ultimately, it is the next solved block that will determine usually determine which of the two competing blockchains is the longest. For example, if Block A and Block B are solved at the same time, but ten minutes later Block C is appended to Block A, then Block A should go on to form the longest blockchain.

2. A stale block is a former competing blockchain which has “failed” in that it has been surpassed in length by a competing blockchain. Stale blocks are also known as orphened blocks.

3. Stale blocks occur when one of two competing blockchains has become the longest blockchain; the “losing” blockchain then becomes a stable block. That is, all of the transactions which had been confirmed by that block are returned to the mempool so as to be picked up by a miner once again.

4. It is important to wait for more than one block to be confirmed when sending or receiving a transaction because there is always the possibility that that first confirmation turns out to be belonging to a stale block. Ideally, one should wait for 6 confirmations so as to be practically certain that the transaction has been confirmed by the BTC network.

[flyingnarwhal]

1. This causes two separate blockchains to form. When this happens, the network continues with the blockchain with the most blocks.

2,3. A stale block is a block that is part of the shorter of the two xhains caused by two miners confirming the same block at once. Stale blocks are returned to the mempool.

4. This helps to prevent double spending by reducing the odds that two miners will confirm the same transaction.

[NicPlankton]

1. The chain divides in two with the two validated blocks, but the network will then choose then the longer chain to keep adding blocks. The longer network depends on which nodes the miner adding another block is validating with.

2. Is a block that was dropped from the blockchain after the chain selected another blockchain path with a chain with more blocks. Creating this stale block and leaving the Txs that were in this block in the mempool again.

3. When two or more miners figure the nonce and hit a lower number than the target asked, then their block with their Txs is added to the blockchain simultaneously, but then if another block is added after one of this block the blockchain would choose the largest chain and leave the other blocks as Stale blocks or orphan blocks.

4. It is important to wait for at least 6 confirmations to verify that the block is confirmed and not staled. Normally a block is added to the blockchain every 10 minutes to avoid stale blocks to occur. And have time to add dropped Txas to the mempool.

[ThiAze]

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

A1 - The bitcoin network receives correct but different versions of Blockchain and one of the two will be considered the predominant version. The predominant version will be the one that presents itself the longest;

2 - What is an stale block?

A2 - It is a dropped block where your transactions will return to the mempool;

3 - How do stale blocks occur?

A3 - They occur when two or more competing miners solve a block at the same time and only one will be predominant. The rest will be dropped and called stale blocks;

4 - Why is it important to wait for confirmation of more than one block when sending or receiving a transaction?

A4 - To avoid increasing orphaned or stale blocks.

[Mr.Flo]

1.The chain splits into two chains. The longest chain will win, the transactions of the other chain will be dumped into the mempool.

2.Dropped block that returned to the mempool (also called orphaned block).

3.When more than one miner mines a block simultaneously. The block that goes on to form the longest chain is confirmed and the other becomes a stale block.

4.To ensure that your transaction gets accepted and doesn’t end up in a stale block and is returned to the mempool.

[Krisztian_Lekrinczki]

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

2. What is a stale block?
   the unaccepted short blockchain.

3. How do stale blocks occur?
   there is more version of the truth, the one which is unchosen becomes a stale block.

4. Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?
   6 confirmations ensure that the block won’t become a stale block

[Ribr]

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

2. What is a stale block?
   Stale blocks are blocks that were valid at one time, gets dropped from the blockchain in favor of a longer chain. The longest chain is considered the “truth”.

3. How do stale blocks occur?
   Stale blocks occur when a longer chain exists and the shorter chain’s blocks are discarded.

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 6 confirmations to avoid transactions being in a stale block.

[Cero]

1.What happens in the bitcoin network when two miners solve a block at the same time?
Blockchain is cointinuing developing in both sides until one of the side win with more confirmed blocks-longer chain.
2.What is a stale block?
Is a block which was unconfirmed in the blockchain. This block was in blockchain which lost - shorter chain.
3.How do stale blocks occur?
With two (or more) chains competing at some point, one will win and belonging blocks are confirmed. Blocks from the other chains are unconfirmed and are called stale or orphaned blocks.
4.Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?
In practice, transaction is confirmed after 6 confirmations or six blocks confirmed in the blockchain after the block involved this transaction. It is confirmed that this block is not stale one.

[Aniruddh_dhoot]

1. Those two blocks will create a split in the chain and it’s up to the miners of next mined blocks which of the “duplicated” blocks hash is used as input for the new blocks to create the longer chain and turn one of those blocks stale
2. A stale block is a block that was once a valid block but lost in “the race” for the longer chain
3. Stale blocks occur when there’s blocks mined with the same height but they do not become part of the longer chain and therefore stale
4. To make sure the transaction is part of a block that belongs to the longest chain and doesn’t become stale. Also if someone is attacking the chain and trying to double spend in the new blocks.

[CyberYeti]

1. In the bitcoin network, when two miners solve a block at the same time nodes closest to each miner will get their block listed first, where one portion of the network will receive one version of the truth and another, another. This creates a temporary fork that will need to be resolved and will be as other miners build onto a particular chain.
2. A stale block is a block that was once placed on the chain for verification but then got dropped because another version was longer without this particular block in its chain. Stale blocks are simply dropped; i.e. sent to the mempool where its transactions can be added later.
3. Stale blocks occur when multiple miners are adding to the chain and different versions/blocks, both valid, start to spread through the chain and a fork is created.
4. It is important to wait for more than one block to be confirmed when sending or receiving a transaction so that you can increase the likelihood that your transaction won’t be dropped; waiting, ultimately with the ten-minute rule gives the network time to synchronize and allow for the singular version of the chain to emerge. The best practice is to wait for six confirmations so that transaction is well established and stale blocks do not develop with a particular transaction in them.

[Roman_Mazuryk]

1. What happens in the bitcoin network when two miners solve a block at the same time?
This leads to temporarily fork of the chain

2. What is a stale block?
A block that is returned into mempool in favor of chain with more POW

3. How do stale blocks occur?
Stale blocks occur after a fork is resolved with a longer chain

4. Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?
To avoid stale blocks

[JPR]

1. What happens in the bitcoin network when two miners solve a block at the same time?
   A fork is created leading to a temporary multi chain.

2. What is a stale block?
   A clock that is dropped in favour of a longer chain with more proof of work. These tx’s are sent back to the mempool.

3. How do stale blocks occur?
   After 2 miners create 2 new blocks simultaneously by accident this fork occurs. This is resolved by new miners attaching to one or other versions of the block chain, once they successfully mine onto the chain, whichever block they did not attach to will be dropped thus securing the integrity of the blockchain.

4. Why is it important to wait for more than one block to be confirmed when sending or receiving a transaction?
   To ensure your tx is not part of a stale block. Best practice is to wait a further 6 blocks in the chain, so roughly 60 minutes to ensure the block in which your transaction lies is not an orphaned block that will be dropped.

[Michi_T]

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

It’s possible that chain will split and then there will be two different chains. We will have two different versions of truth being circulated.

What is a stale block?

Stale Blocks are blocks that are no longer part of the current best blockchain, because they were overridden by a longer chain. They are valid and verrified but have been rejected by the chain and sent to Mempool.

How do stale blocks occur?

If two different miners located for instance in China and Canada successfully find a valid next block at the same time, we have a conflict on the network. Both proposed blocks are valid, but only one can be appended. The 3rd Miner successfully mines a next block. After attaching it to the one of two version of truth, the nodes in America drop the block from the second chain and continue to build on the longest, best current version of the blockchain. That block then becomes a stale block. Network accepts the longest blockchain (the most difficult/best current version of truth). So in the case of splitting a chain, that block will be overridden by a longer chain. It will be then sent to mempool and will wait for validation.

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

Because we want make sure that a block with this transaction won’t be overridden by a longer chain (won’t get dropped/rejected).