Exploiting Our Computational Surroundings for Better Mobile Collaboration

Mobile collaborative environments, being naturally loosely-coupled, call for optimistic replication solutions in order to attain the requirement of decentralized highly available access to data. However, such connectivity assumptions are also a decisive hindrance to the ability of optimistic replication protocols to rapidly guarantee consistency among the set of loosely-coupled replicas. This paper proposes the extension of conventional optimistic replication protocols to exploit the presence of extraneous nodes surrounding the group of replica nodes in an increasingly ubiquitous computational universe. In particular, we show that using such extra nodes as temporary carriers of lightweight consistency meta-data may significantly improve the efficiency of a replicated system; notably, it reduces commitment delay and conflicts, and allows more network-efficient propagation of updates. We support such a statement with experimental results obtained from a simulated environment.