Abstract
In mobile ad-hoc networks, frequent network partitioning and the failure of mobile nodes due to exhaustion of their battery power can considerably decrease data availability. In addition, the increase in network size and node mobility cause the performance of data access to degrade. To deal with these issues, a number of data replication protocols have been proposed in the recent years. This paper surveys the existing data replication protocols in mobile ad-hoc networks and proposes a classification scheme that categorizes the protocols into various classes, with respect to the issues they address. Network partitioning, energy consumption, and scalability are the three issues that are identified in this paper, and which have not been previously considered in the fixed networks. The paper also provides a comparison of the protocols and investigates opportunities for future research.