The Research Of Data Consistency Test Methods Based On Network Packets

With the development of the computer, the data as the enterprise’s important resources ismore and more attention, it is very vital significance to establish a tolerant system that canensure that the data security and service continuity in order to prevent all kinds of disasterdata to damage or destroy. With the tolerant system, when there is a disaster, the data of thelocal data center can be recovery quickly with the backup data center that is provided by thebackup data center, business continuity is also be kept. As a result, damage can be minimum.But if the backup data are not the same as the source data which are before damaged, thebackup data can not to be used for the source data recovery, and the loss will be irreparable.So the data consistency test must be needed between the source data and the backup data inorder to ensure that the backup data in the data recovery are the high available, the dataconsistency test plays a very important role in tolerant system.Now some existing data consistency test technology can be used in the situation that thestructure of the source data and backup data are the same, how to deal with the differentstructure is considered less. A data consistency test methods based on network packets is putforward is this article. In the sender of the source data and the receiver of data backup,WinPcap is used to capture data packets respectively, and a thread is established to improvethe efficiency of catch package. Then the data packets are analysed to get the part of data.And the part of data are divide into many data block and the digest value of the data block arecalculated.In this article the MD5algorithm is chosen as the foundation to calculated the digestvalue. MD5algorithm is improved in efficiency because of the efficiency of the algorithm isalso high requirements in the data consistency test. When the digest value of all data block arecalculated, the digest value should be compared in order to complete data consistency test. Ifthe digest values are the same, the source data and the backup data is consistent, the backupdata can be used for data recovery; If the value is different, the source data and backup isinconsistent and the different number of data block are recorded, the different data block willbe retransmission until the data is consistent. Through the experiment shows that the proposeddata consistency test method is feasible.