Research On Data Consistency In Satellite Network Environment

With the rapid development of satellite networks,architecting distributed systems based on satellite networks to transmit data and store data will be a research hotpot.Due to the high latency and high error link characteristics of satellite networks,communication between servers is often unguaranteed,which poses a great threat to the consistency of the system.The consistency solution adopted in the existing distributed systems and the current consensus protocols are all based on high-speed networks and cannot be directly applied to satellite network environments.Direct application will result in large delays or even lead to the unavailability of the system.Aiming at the problem that the existing consistency solution cannot operate normally under the satellite network environment and considering the dynamic variability of satellite network,this paper designs a distributed consistency solution which is suitable for satellite network environment.This scheme can provide dynamic consistency guarantee according to the current link speed,and can effectively reduce the read and write time while adapting to the multi-variable link.Aiming at the problems of high error rate and high repetition rate of small files in satellite network environment,we propose routing forwarding,data verification,fault tolerance mechanism,data deduplication and other mechanisms,through heartbeat,multiple judgments,and deduplication of small files and other measures to further ensure system data consistency and improve system performance.The test shows that this scheme can adapt to the satellite network environment very well,and can greatly improve the read/write performance under the premise of guaranteeing system consistency and availability.In the case where the network environment has a delay of 100 milliseconds,the 256 Mbyte file write time of this solution is only 1/10 of HDFS;under 300-millisecond latency,the write throughput of this solution is 3.3 times that of HDFS.And the greater the delay,the more obvious the performance advantage of this solution.