Fault tolerance techniques are of vital importance to promise data reliability for mobile distributed system. In mobile environments, nodes suffer from high failure probability and fluctuating bandwidth. Thus, traditional fault tolerance techniques are no longer suitable. In this paper, we present a replica prioritized hybrid fault tolerance strategy combining erasure codes and replicas for a mobile distributed system (MobileRE), to guarantee data reliability with dynamic network status. In MobileRE, we first formulate a reliability cost rate to indicate the cost of ensuring data reliability of the mobile system. MobileRE further adaptively applies the erasure codes and replicas algorithms based on real-time network bandwidth status to minimize system reliability cost rate. MobileRE also obtains the optimal reliability cost rate by customizing redundant configuration parameters. The numerical and simulation results verify the effectiveness of the proposed schemes, and show that compared with traditional designs that only adopt erasure codes or replicas, MobileRE can significantly reduce the system reliability cost rate.

容错技术对于保证移动分布式系统的数据可靠性至关重要。在移动环境中，节点遭受高故障概率和波动的带宽。因此，传统的容错技术不再适用。在本文中，我们为移动分布式系统 (MobileRE) 提出了一种副本优先级混合容错策略，将纠删码和副本相结合，以保证动态网络状态下的数据可靠性。在MobileRE中，我们首先制定了一个可靠性成本率来表示保证移动系统数据可靠性的成本。MobileRE 进一步根据实时网络带宽状态自适应地应用纠删码和副本算法，以最小化系统可靠性成本率。MobileRE 还通过自定义冗余配置参数来获得最佳的可靠性成本率。数值和仿真结果验证了所提出方案的有效性，表明与仅采用纠删码或副本的传统设计相比，MobileRE可以显着降低系统可靠性成本率。