Analysis for REPERA: A Hybrid Data Protection Mechanism in Distributed Environment

Distributed systems, especially those providing cloud services, endeavor to construct sufficiently reliable storage in order to attract more customers. Generally, pure replication and erasure code are widely adopted in distributed systems to guarantee reliable data storage, yet both of them contain some deficiencies. Pure replication consumes too much extra storage and bandwidth, while erasure code seems not so high-efficiency and only suitable for read-only context. The authors proposed REPERA as a hybrid mechanism combining pure replication and erasure code to leverage their advantages and mitigate their shortages. This paper qualitatively compares fault-resilient distributed architectures built with pure replication, erasure code and REPERA. The authors show that systems employing REPERA share with erasure-resilient systems a higher availability and more durable storage with similar space and bandwidth consumption when compared with replicated systems. The authors show that systems employing REPERA, on one hand, obtain higher availability while comparing to erasure-resilient systems, on the other hand, benefit from more durable storage while comparing to replicated systems. Furthermore, since REPERA was developed under the open platform, REPERA, the authors prepare an experiment to evaluate the performance of REPERA by comparing with the original system.