Token-Based Concurrency Control for Transaction Serialization in Replicated Database Systems over Decentralized P2P Networks

This research paper focuses on problems that occur when replicating the database (DB) over large-scale networks. In particular, the emphasis is on the decentralized Peer-to-Peer (P2P) architecture. The motivation is based on the trouble that arises when multiple processes need to simultaneously access the same resource (replica/copy). Often, updates made by refresh transactions from a peer group are performed concurrently on a destination peer. This phenomenon breaks the assurance of the proper execution of transactions and corrupts resource, or make it inconsistent. Therefore, this work proposes a token-based concurrency control approach to serialize refresh transactions performed concurrently by different peers on a copy of a Replicated Database System (RDBS). The algorithmic method and the circulating token ring topology made it possible to realize a distributed mutual exclusion algorithm for transactions serialization in a RDBS over a decentralized P2P network. After an embryonic performance analysis, the result is promising.