Cross layer design for hierarchical routing protocol for wireless ad hoc network

Mobile Ad hoc Networks (MANETs) are becoming popular as a means of providing temporary communication facility among a group of people because MANETs can be set-up and deployed without any infrastructure. MANETs are self-configuring and self-organizing. Routing protocol is the most important element of MANET. Routing protocols for MANET can be broadly classified as proactive routing protocol and reactive routing protocol. In proactive routing protocols like Destination Sequence Distance Vector (DSDV), mobile nodes periodically exchange routing information among themselves. Hence proactive routing protocols generate high overhead messages in the network. On the other hand, reactive routing protocols like Ad hoc On-demand Distance Vector (AODV) and Dynamic Source Routing (DSR) work on-demand. Hence reactive routing protocols generate less number of overhead messages in the network compared to proactive routing protocols. But reactive routing protocols use a global search mechanism called 'flooding' during the route discovery process. By 'flooding' mechanism a source node can discover multiple routes to a destination. 'Flooding' generates a huge number of overhead messages in the network. That huge overhead messages affect the performance of reactive routing protocols in term of network throughput. That kind of performance problem is called 'scaling' problem. Hierarchical Dynamic Source Routing (HDSR) protocol has been proposed to solve that scaling problem. The DSR protocol has been modified to implement HDSR protocol. HDSR protocol reduces 'flooding' problem of reactive routing protocols by introducing hierarchy among nodes. In HDSR protocol, 'flooding' effect is minimized by restricting nodes that should participate in route discovery process based on their status in the network. It is shown that HDSR protocol reduces overhead messages by 80% and reduces end-to-end delay per packet by 70% compared to regular DSR protocol. Hence the network throughput is also increased by 50%. To further improve the performance of HDSR protocol, less congested nodes are selected in route discovery process. In order to do that HDSR protocol is modified to implement a cross layer based routing protocol. It is shown that kind of cross layer based HDSR protocol further reduces delays of HDSR protocol by 20%.;HDSR protocol has an unfair load distribution problem. Because when a mobile node decides to participate in the route discovery process, that mobile node continues forwarding packet from different sources and may be congested eventually. HDSR protocol has been modified to implement Cross-layer based Multi-path Hierarchical Dynamic Source Routing (CMHDSR) protocol. In CMHDSR protocol network traffic is evenly distributed among a set of nodes. Simulations studies show CMHDSR protocol further reduces end-to-end delay of HDSR protocol by 10%.;HDSR protocol has been made energy aware by combining it with an energy aware protocol called Minimum Energy Dynamic Source Routing (MEDSR) protocol. The resultant protocol is called Hierarchical Minimum Energy Dynamic Source Routing (HMEDSR) protocol. It is shown via simulations that HMEDSR not only reduces overhead but it also delivers 1.5 times more packets to the destination compared to DSR protocol.