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.
Keywords: Mobile ad-hoc networks, data management, mobile computing, wireless networks, replication, caching
