Enhanced reliable and energy efficient pressure based data forwarding schemes for underwater wireless sensor networks

Data collection in Underwater Wireless Sensor Networks (UWSN) requires highly optimized communication approach in order to achieve efficient data packet delivery. This approach consists of different communication layers of which routing protocol is an important consideration. Several issues including packet entrapment due to void region, selection of forwarding node with insufficient link quality and packet collision in congested forwarding area have emanated. Therefore, three different research problems were formulated to address the issue of reliability and energy efficiency in data forwarding in UWSN. First, void handling for packet entrapment in the void region, which generate delays and communication overhead. Second, non-optimal node selection that causes forwarding delays and non-reliable packet delivery. Third, collision due to congestion, which leads to packet drop and unreliable packet delivery. Thus, enhanced reliable and energy-efficient pressure-based data forwarding schemes for UWSN were developed, which are the Communication Void Avoidance (CVA) to estimate neighbour nodes availability outside a void region in order to avoid voids and reduce delay; a Multi-metric Evaluation mechanism for next forwarder Node Selection (MENS) for optimal packet delivery; and a Congestion Avoidance and MITigation (CAMIT) in data forwarding for congestion and collision reduction in order to achieve reliable data forwarding. Several experiments were performed through simulations to access the performance of the proposed mechanisms and the results of each scheme were compared with related previously published protocols. The obtained results depict that the proposed schemes outperformed the existing schemes and significantly improved overall performance. CVA improved Packet Delivery Ratio by 12.8% to 18.7% and reduced End-to-end delay by 7.3% to 12.5% on average. MENS improved communication Data Rate by 13.2% to 15.1% and Energy Consumption improved by 10.6% to 15.3% on average. Lastly, CAMIT reduced Packet Drop ratio by 10.2% to 13% on average. The findings demonstrate the improved efficiency has been achieved by the CVA, MENS and CAMIT in terms of optimal node selection and reliability in packet forwarding in UWSN

Geographic and Opportunistic Recovery with Depth and Power Transmission Adjustment for Energy-Efficiency and Void Hole Alleviation in UWSNs

Underwater Wireless Sensor Networks (UWSNs) are promising and emerging frameworks having a wide range of applications. The underwater sensor deployment is beneficial; however, some factors limit the performance of the network, i.e., less reliability, high end-to-end delay and maximum energy dissipation. The provisioning of the aforementioned factors has become a challenging task for the research community. In UWSNs, battery consumption is inevitable and has a direct impact on the performance of the network. Most of the time energy dissipates due to the creation of void holes and imbalanced network deployment. In this work, two routing protocols are proposed to avoid the void hole and extra energy dissipation problems which, due to which lifespan of the network increases. To show the efficacy of the proposed routing schemes, they are compared with the state of the art protocols. Simulation results show that the proposed schemes outperform the counterparts