Abstract
Blockchain has become one of the most significant technology in financial fields. A hash-based blockchain holds the feature of strong tamper resistance. However, it is almost impossible to change fraud transactions in time, since starting a fork requires a lot of time and resources. Failing to remove fraudulent transactions in time is harmful to the entire economic environment. In order to deal with the modification problem, in this work, we propose a novel polynomial-based blockchain structure. Data segments are organized by a Lagrange interpolation method in each block. Polynomial functions are used to keep the order of blocks. The polynomial-based blockchain structure not only achieves the aim of modification but also supports differential control strategy on modification difficulty. Experimental results demonstrate that the polynomial-based blockchain structure is efficient and practical. Detailed theoretical and practical analysis showed that the polynomial-based modifiable blockchain structure has a wide range of application scenarios with the help of other techniques on cryptography and privacy preservation.
•The polynomial-based blockchain structure supports convenient modifications.•The modification difficulty can be changed to fulfill different goals.•The operations have less disturbance to other users and blocks.•Experimental results showed that the novel structure is efficient and practical.