Blockchain Hashing

[alwayscommit]

Consider there are 6 blocks in a blockchain and all have pointers to the previous block. If an attacker changes block 3, the hash of block 3 will change, but will the "previous" field of block 4 have the old hash before the attack (hence indicating a mismatch) or will that field also get updated? The Blockchain Demo shows that someone changes block 3's data, the hash changes and the following blocks' hashes also change at that moment, does that happen at that moment itself? or block 4's "prev" field will have a different hash than block 3's "hash" field... and that's how we know the link is broken because block 4's "prev" hash doesn't match block 3's "hash" field

[PatrickAlphaC]

block 4's "prev" field will have a different hash than block 3's "hash" field... and that's how we know the link is broken because block 4's "prev" hash doesn't match block 3's "hash" field

This is right! Other nodes would be able to verify the chain was wrong quickly

[WaqarTabish2807]

This is correct! Other nodes would be able to rapidly check that the chain was incorrect.