Research On Erasure Code In Storage System Based On DHT

Cloud storage system based on distributed hash table (DHT) has good scalabilityand fast data access ability. Data storage system based on DHT has the dynamic andisomerism, which may cause data loss at any time. Therefore, how to guarantee the highavailability of DHT system become the key problems of DHT storage system.In this paper, redundancy mechanism in cloud storage system based on DHT anderasure code technique based on the cauchy matrix are studied, and the codingarithmetic and data updating strategy of cauchy code are improved. The main work issummarized as follows:1. The design principles of the distributed hash table and basic principles of severalkinds of common DHT protocols are summarized, and analysis of the traditional replicaand erasure code two data redundancy mechanism are made, and principles of the RSerasure code used in DHT storage system is introduced.2. The RS erasure code based on cauchy matrix is analyzed, and an algorithm usedto reduce XOR operation times of finite field operation is given according to thecharacteristics of the operation in cauchy coding process. The experimental results showthat the method can effectively reduce the times of XOR operation in the operationprocess, which has better coding performance than the traditional RS code.3. Careful analysis of the existing two data update strategy is made, and a new dataupdate strategy is given which reduces the operation time of update process throughdistributing the operation to multiple nodes, so as to effectively improve the efficiencyof the data update., The simulation results show that the given data update strategy has ahigher efficiency than traditional update strategy.