Network-level perfromance evaluation and enhancement through multi-layer modifications for AD hoc wireless nanosensor networks

Abstract

Researchers consider wireless nanosensor networks (WNSNs), operating over the Terahertz (THz) band, as a revolutionary emerging network paradigm from the point of its diversi ed applications and contributions to the humanity. Communication over such networks is anticipated to experience di erent challenges due to having unique characteristics such as nano-antenna behavior, small transmission range, limited operating capabilities, etc. Existing research in this eld is still in elementary stage and performance enhancement via designing protocol suit represents a potential issue to address for this eld. However, most of the studies in the literature mainly focus on lower layers, i.e., Physical and MAC layer protocols leaving upper layers such as Network layer and Transport layer protocols still unexplored. Additionally, impact of utilizing classical routing protocols such as AODV, DSDV, and DSR in ad hoc WNSNs is still to be explored in the literature. Therefore, in this study, we explore network-level performance of WNSNs for di erent network settings. First, we develop a system model for WNSNs considering real nano-antenna behavior along with THz communication. Subsequently, we enable these aspects in the network simulator ns-2 through performing necessary modi cations in the simulator. Afterwards, we analyze the network-level performance of WNSNs through adopting classical ad hoc routing protocols such as AODV, DSDV, and DSR for di erent transmission ranges, di erent number of nanosensors, and di erent MAC alternatives. Next, utilizing results of the performance analysis, we propose a hierarchical AODV routing protocol for Network layer and an acknowledgement-based UDP protocol for Transport layer with a goal of enhancing network-level performance in ad hoc WNSNs. Finally, we evaluate performance of our proposed protocols and compare with existing protocols in ns-2 based on the performance metrics such as network throughput, end-to-end delay, total energy consumption, energy consumption per bit, packet delivery ratio, and packet drop ratio.