Research On The ASL-DHT Algorithm And Its Application In Data Outsourcing Model

Distributed Network System is provided with the advantages of the shared resources, convenient communication, real-time control, risk decentralization and so on, and has entirely adapted to the development trend of information society with broad prospects. However, in Distributed Network System, electronic data and information can be quickly and widely copied, spread abroad and modified in batches, leading the data and information to be source-unidentifiable, compromised or tampered with. Thus ensuring data integrity and source-reliability is becoming an important research topic in distributed network field.In 2000, Scholar Goodrich et al. put forth Authenticated Data Structure Model, which can commendably solve the three-party data authentication problems in unreliable distributed environment. On the in-depth study of Goodrich's authenticated Skip List algorithms, based on the thinking of separating the hash scheme and data storage scheme, this paper proposes a new set of algorithms of authenticated Skip List based on directed hash tree, ASL-DHT for short; gives the design ideas and specific description of the algorithms including characteristic value calculation, element insertion, deletion, search and verification; applies probability theory and mathematic statistics methods to cost analysis, and makes a algorithm simulation to compare with that of authenticated Skip List. Experiment results show that, compared with the original algorithm, ASL-DHT algorithm has got great improvement on storage structure, search and verification mechanism, as well as element-update strategy, and offers greater performance optimization on time and space costs.The another part of work consists of bringing forward an Authenticated Data Structure Model based two-party data authentication model which is applicable for data outsourcing scenario, applying ASL-DHT algorithm to the model, and designing and implementing a two-party data authentication model based prototype system for data outsourcing, so that the integrity and certifiablity of outsourced data is guaranteed. The results show that the two-party data authentication model based data outsourcing has both great theoretical significance and practical value with high efficiency in time and space.