Forming an unchanged chain of pools
The Credits platform stores data in the form of a sequence of blocks, the order of which is determined by the time of their addition. In case of block rearrangement, the order of time marks will be incorrect and the hash sums will not correspond to the initial data, which would render them incorrect.
Blockchain is formed as a constantly growing chain of blocks with records of all transactions. Each block consists of a header and a list of transactions. The block header includes its hash and the hash sum of the previous block. Thus, each new block refers to the hash of the previous block in the registry. And the formation of a hash sum guarantees the irreversibility of the entire transaction chain. Changing the information in a block that is already in the chain is inadvisable, since in this case it would be necessary to edit the information in all subsequent blocks. Thanks to this successful double-spending attack (re-spending previously expended funds) in practice is extremely unlikely.