Enhanced Scheme for Video Transmission over Mobile Ad hoc Networks based on Optimized Link State Routing Protocol

Abstract

A Mobile Ad Hoc Network (MANET) is an infrastructure-less wireless network which allows a group of mobile devices to connect wirelessly without centralized administration. MANETs are useful when rapid deployment in infrastructure-less locations is required, or under emergency situations where communication is not available. Video conferencing over MANET is challenging due to features that characterize this type of network. This thesis proposed an enhanced scheme based on tuning, modeling, and optimizing the Optimized Link State Routing (OLSR) protocol behavior. The objective is to overcome MANET challenges including Quality of Service (QoS), energy consumption, and security. The novelty of the proposed scheme comes through using an optimal configuration of OLSR protocol which changes the protocol behavior by modifying the HELLO and Topology Control (TC) message intervals to cope with most desirable QoS metrics for transmitting video conferencing traffic over MANET such as (end-to-end delay, Packet Delivery Ratio (PDR%), Jitter, throughput, and WLAN-load). In addition, the proposed scheme provides low energy consumptions compared to conventional OLSR and maintains network QoS when under different security attacks such as black hole attack on the network layer and jamming attack on MAC/PHY layer. Simulation is carried out using OPNET 14.5 to show the impact of the new configuration of OLSR on scalability (network size and nodes density) and mobility speed. Analysis of Variance (ANOVA) and Particle Swarm Optimization (PSO) algorithm were used to model and optimize the OLSR behavior, respectively. Obtained results showed that the new optimized configuration of OLSR routing protocol compared to conventional OLSR copes with most QoS challenges in terms of E2E-delay and jitter which were decreased by 27%, and 47% respectively, throughput and PDR% increased by 38% and 29% respectively. In addition, when the network enlarges and the mobile density increases the QoS is not degraded. Also, the optimized configuration of the OLSR protocol provides low power consumption due to adaptive behavior in case of network topology changes. The power dissipated for sent/received packets dropped by 40%. The new fine-tuning of OLSR maintained QoS under two popular attacks: black hole and jamming attacks. The proposed scheme is promising for transmitting video conferencing traffic effectively over MANETs.