Security Modeling Algorithm Optimization for Smart Contracts in the Digital Economy Based on Blockchain Technology

This study aims at the optimization of the blockchain security modeling algorithms in digital economy smart contracts. From a theoretical perspective, this study proposes a smart contract security enhancement method based on blockchain technology. First., the existing blockchain security mechanism is comprehensively analyzed by reviewing the latest research results. The model focuses on the access control vulnerabilities, consensus mechanism risks and data tampering issues of smart contracts. On this basis, this study designs an optimization algorithm that combines sliding window segmentation, time series feature extraction and multi-layer security strategy. Such fusion operations can improve the security and anti-attack capabilities of smart contracts. In addition, the echo state network (ECHOSN) is introduced to conduct smart contract risk assessment. This operation further enhances the stability of smart contracts. The experiment is verified using real blockchain network data SmartBugs. The results show that the optimization algorithm is significantly better than the traditional method in reducing the risk of data tampering. The accuracy (99.24%) and F1 value (93.67%) can meet the accuracy requirements in real scenarios.