i know this is digressing off the OP's question. i still think its worth mentioning to teach people
IIRC most blocks after a block (if not every block) basically verifies the transaction and that's why older transactions can have insane amounts of verification under them. So if you really want to make sure that there was a secure transactions, just wait a few years and it should hit 1k confirmations pretty soon.
That's completely unnecessary, of course, however it's an interesting thought experiment.
firstly: every new block has a hash which is the proof of validity. every new block contains a hash of the previous block
this means it does not need to validate every transaction of every previous blocks because the hash of a block is the proof of validity of said previous block.
chaining the blocks together (blockchain) by having each blockhash linked to the next block means, if the latest block validates then automatically the previous blocks are then more secure as it is more tightly locked in.
in short. if you wanted to change a transaction 10 blocks ago. you cannot just change the transaction and slide it in unnoticed.
changing a transaction results in a different blockhash, which doesnt match the one saved in the next block(9 blocks ago). so changing the saved hash in the next block, causes that blocks hash to change(8 blocks ago). and so on
meaning in order to change a transaction 10 blocks ago. while the network continues making new blocks
you need to go back and do your alteration. and then make a block with a new hash
then need to then remake the 9 blocks above it with their new hashes each time..
and then keep going for every new block that appeared while you were messing around, until you overtake the networks account of the newest block. which is not a simple task.
secondly: ~144 blocks are created a day. so you will get 1k confirms just waiting a
weekYeah i agree because i seen my old transaction to the present transaction they have different counted confirmation ..
But the question why this is happening.
every time a new block is created ontop. that block only validates the transactions within its own block. but adds a hash of the previous block
thus chaining the blocks together without having to revalidating previous blocks again.
in short if a new block is created. your full node software is not going to recheck every transaction of the last 432400 blocks.
its the hashes of the block that has already done the previous validation. and new blocks just continuing to link chains of the hashes ensuring everything is valid.
this link to a previous topic will explain
https://bitcointalk.org/index.php?topic=1627797.msg16369773#msg16369773
