Abstract: Real data are the precondition for the smart water system to make correct decision. Aiming at low-throughput public blockchain, low-throughput consortium blockchain and a large amount of data of smart water, the monitoring platform of the sponge city is used as an example to devise a regulatory method based on the private chain. The hash tree is built with real-time data collected by sensors and this is signed by the timestamp server. The timestamp signature, timestamp, hash root, etc. are stored in the block head of the private chain. Non-root vertices of the hash tree are stored in the block body. The private chain is used as the supporting document of smart water data. In this method, the signature can’t be forged and the cost of the blockchain forgery is high, which ensure that the data are hard to be tampered. The experiments show that the period when the data are tampered and the sensor device number of the tampered data can be found, and the validity of the timestamp signature can be validated in this method.

Key words: smart water, sponge city, data monitoring, private blockchain, time series data

摘要： 真实的数据是支撑智慧水务系统正确决策的前提条件。针对联盟链、公有链吞吐量低的问题与智慧水务中数据量大的特点，以某智慧水务框架下的海绵城市运行监管平台为例，设计并实现一种基于私有链的数据监管方法。该方法以传感器实时数据构建哈希树，将哈希树根交给时间戳服务器签名；时间戳签名、时间戳、哈希树根等存储在私有链区块头中，其余哈希树非根顶点存储至区块体中。以此私有链作为运行监管平台时间序列数据的证明文件，具有签名很难伪造和证明文件伪造成本高的特点，可达到证明文件难以被篡改，且可高效检测出被篡改数据的目的。实验结果表明，该方法可发现被篡改数据的时间段、被篡改数据的传感器编号以及验证数据时间戳签名的有效性，在篡改时基于内存难度的Cuckoo Cycle算法较基于计算难度的算法需要更多的硬件成本。

关键词: 智慧水务, 海绵城市, 数据监管, 私有链, 时间序列数据