In the blockchain, the front block and the back block are pointers formed by linking. Chain hashing is a method of linking blocks together using encryption technology, so that each block depends on the hash value of the previous block. Specifically, each block in the blockchain contains transaction data and some metadata, such as the generation time and hash value of the block.
When a new block is created, the metadata will be hashed with the transaction data to generate a new hash value. This hash value will be used as the "fingerprint" of the new block to link it to the previous block.
In order to achieve this, all nodes in the blockchain network will maintain an open "blockchain" database, which contains all published blocks and their corresponding hash values. When a node receives a new block, it will check whether the hash value of the block matches the hash value of the previous block.
If it matches, it means that the new block is valid and linked to the correct location. If it does not match, then this new block will be rejected, which may lead to transaction failure or blockchain splitting.
This chain hashing technology ensures the integrity of blockchain, because any tampering or addition may lead to the change of hash value, which will be detected by other nodes. In addition, because each block depends on the hash value of the previous block, attackers usually need to tamper with multiple blocks at the same time to tamper with the entire blockchain. To sum up, the chain hash technology in the blockchain links the front and back blocks together by using cryptographic technology, thus ensuring the integrity and security of the blockchain.