Delay and energy efficient dynamic bandwidth allocation algorithm for hybrid optical and wireless sensor networks

Abstract

Abstract Wireless sensor network (WSN) in the hybrid optical and WSN (HOWSN) utilizes full advantages of broadband access facility. Passive optical network (PON) as the backbone of HOWSN ensures energy efficiency and meets the higher bandwidth demands. However, in the conventional HOWSNs, the sensor nodes of WSN stay in active state for 100% time, i.e., 100% duty cycle, with the optical access networks cause huge amount of energy wastage. This paper presents a new delay and energy efficient (DEE) dynamic bandwidth allocation (DBA) algorithm with multi-threaded polling approach for the optical network units of the HOWSNs. In the proposed scheme, to conserve the energy consumption of HOWSNs, the optical network units (ONUs) connected to the gateway nodes of WSN use 10% duty cycle, whereas the ONUs connected to the data network use 100% duty cycle. The performance of the proposed DEE scheme is evaluated by numerical simulations and compared those to the existing adaptive limited DBA (ALDBA) schemes, i.e., ALDBA1, ALDBA2 and ALDBAM, of HOWSNs. The simulation results prove that the proposed DEE scheme provides up to 32% and 38% more energy savings with lower end-to-end packet delay compared to the existing ALDBA1, ALDBA2 and ALDBAM schemes of HOWSNs, respectively.