Swarm intelligent routing in managing congestion-awareness and performance in mobile ad hoc networks

Abstract

Mobile ad hoc networks (MANETs) are infrastructureless temporary networks that can be deployed in areas that do not have predefined communication infrastructure, for example, earthquake-stricken areas. The dynamism of MANET network where nodes joins and leave the network anytime make routing decision a challenge. Routing of data packets in mobile ad hoc networks (MANETs) is a non- deterministic polynomial (NP) hard problem. Past scholars have been focusing on number of hops on determining the best path to route data packets on the network. Determining shortest path using number of hops method oblivious of congestion of the next-hop neighbours is detrimental to the performance of wireless ad hoc network, because it can ultimately result in high packet dropping rate especially on highly congested nodes in the network. Extending network lifetime by exploring on the congestion levels and stability factor of nodes in MANETs have not been addressed by past scholars. In this thesis a cooperative Queuing-Swarm based routing framework has been proposed. The contribution from this thesis were as follows: (1) development of a new routing method called Queuing with Particle Swarm Optimisation (Q-PSO). Q-PSO divides the MANET into logical groups and selects the cluster head depending on remaining battery life. Simulation results in both single path and multipath routing showed that the proposed Q-PSO performed better in terms of packet deliver ratio, average jitter, etc. relative to other swarm-based routing techniques and (2) the development of Queuing Ant Colony System (QUACS) routing method. QUACS method checked for node stability and the congestion metric of all possible next-hop neighbours before choosing the node to relay data packets. Performance evaluations of QUACS routing methods showed better results in terms of average end-to-end delay, throughput, etc. relative to other routing methods. Hybridising swarm intelligence with queuing optimisation in MANETs helped in extending the network lifetime and enabled quick information exchange. The proposed two routing methods can also help future MANET researchers who would want to explore more on wireless networks.