Postgraduate entrance examinations include blockchain-related majors.

To put it simply, blockchain is a computer technology that is the same as the Internet. To be more complicated, blockchain is an electronic data storage method.

Introduction

To be more complicated, blockchain is an electronic data storage method. Data appears in the form of blocks. These blocks are all linked together. , giving its internal data immutability. When a data block is linked to this chain, its internal data can no longer be changed. The data inside is publicly visible to anyone.

The cryptographic hash function is an extremely complex mathematical formula. Substituting any data string as an input value into the formula can obtain a unique 64-bit output value, but the input value cannot be deduced from the output value.

The blockchain protocol will predetermine some requirements. For example, on the Bitcoin blockchain, the corresponding block can only be uploaded to the chain if the digital signature begins with no less than 10 consecutive zeros. To obtain a qualified block digital signature, you need to repeatedly change the input data string until a signature starting with 10 consecutive zeros can be generated.

Changing a block will cause its signature change to be inconsistent with subsequent block records, thus disconnecting the subsequent blocks. You want other participants in the network to accept this change. The block that has passed must be relinked to the subsequent block.