A new non-blocking validation protocol for eager replication of databases over a decentralized P2P architecture

Abstract

Replicating a database on a decentralized P2P network using the eager approach is a difficult problem, especially since participants (peers) are dynamic on such kinds of networks. A second defect is conflicting transactions executed concurrently by different peers to update the same data. These problems cause the perpetual abortions of transactions so that replicas remain always inconsistent. Thus, this article introduces a new Four-Phase-Commit (4PC) validation protocol that allows the completion of transactions with available peers and recovers unavailable ones when they re-join the network. Nested transactions and distributed voting technique were used to arrive at an algorithm that was implemented with C#. An experimentation scenario has made it possible to measure its performance and has finally revealed that the new algorithm is effective because in real-time it can replicate a large number of records; it can queue the records of the absent peers in order to distribute these updates to them when they become present again.