Evaluation of Optimistic Replication Techniques for Dynamic Files in P2P Systems

Abstract

Replication techniques are commonplace in P2P computing systems. Initially, the objective of such techniques was to ensure availability of immutable information (typically files) in P2P systems under highly dynamic nature of large P2P systems. But also dynamic documents, which are documents that change over time, can be replicated. In this case, consistency issues must be addressed. It is therefore interesting to study different replication techniques for dynamic files in the context of a peer-group. In this paper, we propose a replication system for documents structured as XML files and evaluate them under different scenarios. The proposed system has a super-peer architecture that provides fast consistency for late joining peers. It uses optimistic replication techniques with propagating update operations from source node to destination node in push mode. The system is suitable for asynchronous collaboration, which arises in online collaborative teams accomplishing a common project in a P2P environment.