Replica Dissemination and Update Strategies in Cluster-Based Mobile Ad Hoc Networks

Abstract

A mobile ad hoc network (MANET) is a collection of wireless mobile nodes that forms a temporary network without the aid of a fixed communication infrastructure. Since every node can be mobile and network topology changes can occur frequently, node disconnection is a common mode of operation in MANETs. Providing reliable data access and message delivery is a challenge in this dynamic network environment. Caching and replica allocation within the network can improve data accessibility by storing the data and accessing them locally. However, maintaining data consistency among replicas becomes a challenging problem. Hence, balancing data accessibility and consistency is an important step toward data management in MANETs. In this paper, we propose a replica-based data-storage mechanism and undelivered-message queue schemes to provide reliable data storage and dissemination. We also propose replica update strategies to maintain data consistency while improving data accessibility. These solutions are based on a clustered MANET where nodes in the network are divided into small groups that are suitable for localized data management. The goal is to reduce communication overhead, support localized computation, and enhance scalability. A simulation environment was built using an NS-2 network simulator to evaluate the performance of the proposed schemes. The results show that our schemes distribute replicas effectively, provide high data accessibility rates and maintain consistency.