Final answer:
If a user tries to change information in a single block of a blockchain, the cryptographic hash of the block would change, invalidating all subsequent blocks. This alteration would be detected by the network's consensus mechanism, making it nearly impossible to change block information without network agreement.
Step-by-step explanation:
When Distributed Ledger Technology (DLT) is used in a blockchain, each block contains transaction data, a timestamp, and a cryptographic hash of the previous block, creating a chain of blocks. If a user tries to change the information in a single block, they would alter the block's hash. Because each subsequent block contains the previous block's hash, this change would invalidate all subsequent blocks. The blockchain network achieves consensus by requiring the majority of nodes to agree on the validity of the blocks, making it extremely difficult to alter any single block without consensus.
Consensus mechanisms like Proof of Work or Proof of Stake require significant computational work to add a block, and altering a block would require redoing this work for each subsequent block, which is practically infeasible. This design provides security and trust in the blockchain, ensuring that once a transaction is recorded, it is extremely difficult to change retroactively without being detected by the network.