Abstract: Abstract: In response to the challenges in the digital transformation of government services, including complex credential verification processes, limited credential sharing, and users repeatedly applying for credentials, a Blockchain based identity authentication scheme for cross-departmental collaboration in e-government was proposed. Firstly, a Verifiable Credential (VC) and Verifiable Credential Proof (VC Proof) mechanism were designed, storing credential hash values and proof information on the blockchain to enable efficient multi-departmental credential verification. Secondly, an authorization credential mechanism was constructed to facilitate credential interactions between verifiers and relevant departments, thus reducing the burden on users to repeatedly apply for credentials. Finally, a smart contract-based non-interactive zero-knowledge proof technique was introduced to ensure VC privacy while completing identity authentication. Experimental results show that the verification gas consumption remains low, stabilizing around 500 Gas, and the gas consumption for contract deployment increases linearly with contract size. Further analysis reveals that when verification gas consumption is 140.55 Gwei, transactions per second reaches its peak, while increasing verification gas consumption to 562.562 Gwei causes TPS to drop to approximately 200. Moreover, compared to Ethereum experimental results, the proposed scheme demonstrates better performance under the same concurrency conditions, reducing the average response time by approximately 0.32 seconds.

Key words: blockchain, cross-departmental collaboration, identity authentication, verifiable credentials, zero-knowledge proof

摘要： 摘 要: 针对政务服务数字化转型过程中跨部门协作身份认证存在的凭证验证流程复杂、凭证共享受限及用户多次往返申请凭证等问题，本文提出了一种基于区块链的政务跨部门协作身份认证方案。首先，设计可验证凭证（VC）及其存在性证明（VC Proof）机制，将凭证哈希值及证明信息存储至区块链，以实现多部门间的高效凭证验证；其次，构建授权凭证机制，使验证方与相关部门进行凭证交互，从而减少用户重复申请凭证的负担；同时，引入基于智能合约的非交互式零知识证明技术，在保障VC隐私的前提下完成身份认证。实验结果表明，本方案的验证Gas消耗较低，稳定在500 Gas左右，且合约部署的Gas消耗随合约规模呈线性增长。进一步分析发现，当验证Gas消耗为140.55Gwei时，TPS达到最高，而增至562.562 Gwei时，TPS下降至约200。此外，与以太坊实验结果相比，本方案在相同并发环境下展现出更优的性能，平均响应时间降低了约0.32s。

关键词: 区块链, 跨部门协作, 身份认证, 可验证凭证, 零知识证明