How do blockchain conformation work?

[Nheer]

For a time now, I've been trying to learn more about the technical side of bitcoin, and I've heard that I can do so here. I so made the decision to ask here in the hopes of discovering a better explanation for some of the things I don't understand.

I discovered that a blockchain system consists of numerous nodes dispersed over the globe, each of which keeps, confirms, and updates its own copy of the ledger upon the creation of a new block of transactions.
I don't seem to comprehend how more blocks increase transaction security. And How do blockchain confirmations work?

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[Charles-Tim]

For me not to repeat myself, you can read this:

Re: Why difference in 6 blocks is enough to think the transaction is secure?

Just know that it is pertaining to chain reorganization and the fear of a transaction that has been confirmed to later be seen as not confirmed. But which likely that the transaction would be confirmed again.

But also about the fear of using a low fee in which the mempool is congested to the extent that a low fee transaction is dropped from mempool.

[BlackHatCoiner]

I don't seem to comprehend how more blocks increase transaction security.

If your transaction was just confirmed on the last block, it only takes the cost to produce that block to reverse it. If the transaction was confirmed on the second-to-last block, then it takes the cost to produce 2 blocks to reverse it, because just re-producing the block your transaction was confirmed isn't enough; if you redo the work for that block, you invalidate the next ones, so you have to redo the work for all the next blocks.

[ABCbits]

I don't seem to comprehend how more blocks increase transaction security.

Aside from what @BlackHatCoiner said. Higher confirmation also reduce risks of your transaction become unconfirmed again due to block re-org. See https://learnmeabitcoin.com/technical/chain-reorganisation.

And How do blockchain confirmations work?

Basically it means depth of the block which contain certain transaction. The number increased automatically each time new block is mined.

[Nheer]

Thank you all for the kind gesture for making understand what I asked this place is truly where one can get to know about bitcoin and cryptocurrency. I have come across some helpful posts even though its my first day I believe there are quite a lot i can learn here.

[NotATether]

I don't seem to comprehend how more blocks increase transaction security.

Aside from what @BlackHatCoiner said. Higher confirmation also reduce risks of your transaction become unconfirmed again due to block re-org. See https://learnmeabitcoin.com/technical/chain-reorganisation

Well ultimately, even in the case that a reorg happens, your transaction will be included in another block again but this time it will be buried under a bunch of other blocks, which should not be a problem to most businesses as they are accepting transactions with at least 2-3 blocks depth. So where is the risk here?

[alexeyneu]

If your transaction was just confirmed on the last block, it only takes the cost to produce that block to reverse it. If the transaction was confirmed on the second-to-last block, then it takes the cost to produce 2 blocks to reverse it, because just re-producing the block your transaction was confirmed isn't enough; if you redo the work for that block, you invalidate the next ones, so you have to redo the work for all the next blocks.

disagree. to reverse something you gonna pretend on that your blockchain is right and other one is wrong. you either have a reason for that or you don't. how it'll end up will not be based on confirmations most likely. So all this is about unconfirmed vs confirmed tx , count doesn't metter much. unconfirmed tx can be just rejected without reason specified(to you).

[pooya87]

disagree. to reverse something you gonna pretend on that your blockchain is right and other one is wrong.

That is not how bitcoin works. All the consensus rules are clearly defined and are enforced by each individual node. There is nothing to "pretend", the nodes will always follow the chain with the most amount of work.

Once a node validates a transaction, it propagates the transaction to other nodes in the network. If the majority of nodes in the network agree that the transaction is valid, it is added to a block of transactions.

That is not how bitcoin works.
Node verify transactions for themselves not for the network. The miner is also using its own node (or the pool that is using its own node) and if that node considers a single transaction that nobody else has seen or verified, it still can be added to the block they mine.

Once a block is added to the blockchain, it is considered confirmed. The confirmation process involves adding the block to the end of the blockchain and creating a unique hash that links the new block to the previous block. This hash creates an unalterable record of the transaction on the blockchain.

Not entirely correct. Confirmation is the other word for mining a block which is the process of finding a hash that is smaller than or equal to the target. The hash you find doesn't link the new block to the previous one, the fixed 32 byte hash inside the header that you mined is the link to the previous block.

The number of confirmations a transaction needs depends on the rules of the specific blockchain network. In general, the more confirmations a transaction has, the more secure it is considered to be, as it becomes increasingly difficult to alter or reverse the transaction with each new block added to the blockchain.

There aren't exactly any rules about number of confirmations in each cryptocurrency. It is more like the result of the other rules that exist in that cryptocurrency. For example an altcoin with "fast" blocks requires a lot more confirmations to have the same security. Or an altcoin with low hashrate that can be easily 51% attacked or a centralized altcoin with a mutable blockchain can never be secure no matter how many confirmations there are.

[alexeyneu]

finally it'll be decided by bitcoin/bitcoin repo holders when they'll hardcode next control point .

Bitcoin Core checkpoint haven't been updated in many years though. Current highest checkpoint is only at block height 295000 with block hash "0x00000000000000004d9b4ef50f0f9d686fd69db2e03af35a100370c64632a983"[1].

[1] https://github.com/bitcoin/bitcoin/blob/v24.0.1/src/chainparams.cpp#L148-L164

original message is

and one more:  your tx goes as confirmed in one place (say blockchain.com) and as "not found" in another Say on binance . In case of troubles you're asking about it'll be exactly like that. finally it'll be decided by bitcoin/bitcoin repo holders when they'll hardcode next control point . check bsv story on latter

[NeuroticFish]

your tx goes as confirmed in one place (say blockchain.com) and as "not found" in another Say on binance . In case of troubles you're asking about it'll be exactly like that. finally it'll be decided by bitcoin/bitcoin repo holders when they'll hardcode next control point . check bsv story on latter

You seem to have no idea what you're talking about. Binance is a centralized exchange. Whatever happens in their internal data (mostly trades) doesn't reflect on the blockchain. Only the actual deposits and withdrawals do. Plus, binance has no block explorer. Plus, Binance may convince those who don't understand bitcoin to withdraw wrapped bitcoin (ie on a different blockchain); this last one may make transactions "made by binance" not be visible, but not the other way around.
If Binance cannot find a deposit made on the actual bitcoin blockchain, then they have an error.

BSV is a shitshow, not a story. BSV was greatly centralized. This allowed CSW push code that offers him control.
BTC is still decentralized and I expect the vast majority of BTC users would not accept such a change (at the very least they would not update to that version).

[alexeyneu]

BSV is a shitshow, not a story. BSV was greatly centralized. This allowed CSW push code that offers him control.

and all answers to this bs is removed. so who runs this forum really?

( https://bitcoinmagazine.com/technical/one-day-after-bitcoin-cash-hard-fork-takeaways-and-latest-developments )