Block-based access refers to how transactions and data are organized and retrieved on a blockchain. In this system, information is stored in blocks, which are linked together in a chronological chain. Each block contains a set of transactions, along with a unique identifier called a hash that connects it to the previous block.

When a new transaction occurs, it is processed and added to a new block. Once the block is filled, it gets validated by the network through consensus mechanisms like proof of work or proof of stake. After validation, the new block is appended to the existing chain, making the transaction permanent and immutable.

Accessing data in this structure is done by referencing specific blocks. Users can view transaction histories, balances, and other relevant information by querying the blockchain.

This ensures transparency and security, as all data is publicly accessible and cannot be altered retroactively without consensus from the network. Overall, block-based access enables efficient and secure management of digital assets, fostering trust among users.