Remote File Synchronization Algorithm Research And Applications

With the popularization of personnel computer and the rapid development of information technology, our life more and more depend on the information technology. Information has become one of the most valuable intangible assets of enterprises and individual. Great loss will be brought to these enterprises and individual once data are lost and damaged. Backup is an effective method for ensuring the safety of data[1]. backup at remote terminal has higher safety and credibility to prevent incidents, such as the September terrorist attack and WenChuan earthquake on May 12.A good remote file synchronization algorithm is the key and core of success of remote file backup system. rsync algorithm is the remote file synchronization algorithm which is most widely applied now. The emphasis of this thesis is to study rsync algorithm and its application in remote file backup system. The main works of this thesis are as follows:1. The rsync algorithm's shortage in practice is analysed. We improve rsync algorithm in such aspects:(1) The rsync algorithm's chunking method is improved by content dependent chunking algorithm, so we can resolve the problem that calculation is not equal in rsync algorithm;(2) The rsync algorithm's synchronization round is improved by multi-roundtrip remote synchronization, so we can resolve the problem that rsync algorithm is invalid when processing the worst case;(3) The rsync algorithm's network traffic which mainly caused by transporting diff data is reduced by using differential compression technology;(4) The rsync algorithm's file reconstruction way is improved by using inplace reconstruction;(5) The rsync algorithm's synchronization way is improved by using bi-direction synchronization technology; 2. We propose an remote file synchronization algorithm called fbrsync algorithm for remote file backup system based on our research results and rsync algorithm. This algorithm combines content dependent chunking algorithm, multi-roundtrip synchronization, differential compression and inplace reconstruction. Its object is applied into remote file backup system to realize effective and fast remote file backup;3. We design and realize the embodiment applying remote file synchronization algorithm: Remote File Backup and Recovery System;4. We realize various improvement ways in the fbrsync algorithm by programming, display precise experimental data and carry out comparative analysis.In conclusion, this thesis mainly studies rsync algorithm and its application in remote file backup system. we analyze it's shortage in practice, and effectively improves the algorithm about these shortages. We propose an algorithm called fbrsync algorithm based on these improvement ways and rsync algorithm. This algorithm can realize effective and fast remote file backup in remote file backup system.We design and realize the embodiment applying remote file synchronization algorithm: Remote File Backup and Recovery System. We realize these improvement ways in the fbrsync algorithm by programming, display precise experimental data and carry out comparative analysis.