Energy-Efficiency Routing algorithms in Wireless Sensor Networks: a Survey <s> Routing Algorithms <s> Wireless sensor networks consist of small nodes with sensing, computation, and wireless communications capabilities. Many routing, power management, and data dissemination protocols have been specifically designed for WSNs where energy awareness is an essential design issue. Routing protocols in WSNs might differ depending on the application and network architecture. In this article we present a survey of state-of-the-art routing techniques in WSNs. We first outline the design challenges for routing protocols in WSNs followed by a comprehensive survey of routing techniques. Overall, the routing techniques are classified into three categories based on the underlying network structure: flit, hierarchical, and location-based routing. Furthermore, these protocols can be classified into multipath-based, query-based, negotiation-based, QoS-based, and coherent-based depending on the protocol operation. We study the design trade-offs between energy and communication overhead savings in every routing paradigm. We also highlight the advantages and performance issues of each routing technique. The article concludes with possible future research areas. <s> BIB001 </s> Energy-Efficiency Routing algorithms in Wireless Sensor Networks: a Survey <s> Routing Algorithms <s> As the sensor layer of Internet of Things (IOT), enormous amount of sensor nodes are densely deployed in a hostile environment to monitor and sense the changes in the physical space. Since sensor nodes are driven with limited power batteries, it is very difficult and expensive for wireless sensor networks (WSNs) to extend network lifetime. In order to achieve reliable data transmission in WSNs, energy efficient routing protocol is a crucial issue in extending the network lifetime of a network. However, traditional routing protocols usually propagate throughout the whole network to discover a reliable route or employ some cluster heads to undertake data transmission for other nodes, which both require large amount energy consumption. In this paper, to maximize the network lifetime of the WSN, we propose a novel energy efficient region source routing protocol (referred to ER-SR). In ER-SR, a distributed energy region algorithm is proposed to select the nodes with high residual energy in the network as source routing node dynamically. Then, the source routing nodes calculate the optimal source routing path for each common node, which enables partial nodes to participate in the routing process and balances the energy consumption of sensor nodes. Furthermore, to minimize the energy consumption of data transmission, we propose an effective distance-based ant colony optimization algorithm to search the global optimal transmission path for each node. Simulation results demonstrate that ER-SR exhibits higher energy efficiency, and has moderate performance improvements on network lifetime, packet delivery ratio, and delivery delay, compared with other routing protocols in WSNs. <s> BIB002 </s> Energy-Efficiency Routing algorithms in Wireless Sensor Networks: a Survey <s> Routing Algorithms <s> Abstract In most cases, wireless sensor networks (WSNs) are deployed in unattended scenarios and are featured by energy sensitivity and low cost, thus making the performance of WSNs prone to the impact of external environment and internal energy. Existing routing protocols attempted to optimize the energy efficiency and routing reliability from the perspective of the network itself and failed to take into consideration the environmental impact from outside, causing them cannot make prompt reactions to the dynamic changes of the environments (e.g., wildfire). Thus, in these routing protocols the routing survivability under harsh environments is questionable. To tackle this issue, the paper proposes an environment-fusion multipath routing protocol (EFMRP) to provide sustainable message forwarding service under harsh environments. In EFMRP, routing decisions are made according to a mixed potential field in terms of depth, residual energy and environment. The basic idea of this approach is to instruct data packets to select routes with the best trade-off among latency, energy conservation and routing survivability. As the environmental field is constructed and updated using the sensing capability of WSN itself, constructed routes can avoid crossing through the danger zones to keep the paths safe. To enhance the performance of EFMRP, specific maintenance, traffic allocation and retreat mechanisms are proposed. We investigate the impact of configuration parameters and paths number on the routing performance respectively and compare EFMRP with respect to commonly used routing protocols. The experimental results show that EFMRP can obtain significant improvements in packet delivery ratio and network lifetime under harsh environments. <s> BIB003
The literature on WSN's routing protocols contains several studies presented below. Authors in BIB001 Presented a study of wireless sensor network routing protocols, this survey classifies network-based routing techniques into three classes: the hierarchical, flat and location-based routing protocols. These protocols are also classified as negotiation-based, multi-path, query-based and QoS-based protocol routing methods. Authors in  have presented a classification of protocol routing and design problems, as well as a protocol for routing based on their features and mechanisms, without giving any information about each of the protocols described. Authors in BIB003 have suggested an Environment-fusion multipath routing protocol (EFMRP) multi-path environment-fusion routing, and this includes a potential field modelling method for instructing data packets to reach the sink. Maintenance, traffic distribution and retreat mechanism design. In BIB002 , researchers discussed the issue of the energy balance and minimisation in WSN's energy consumption. Authors have developed an energy distributed area algorithm to select high energy nodes dynamically as source routing nodes which serve to calculate the route for other common nodes. In addition, the authors present the effective distance as a criterion for the optimal transmission distance and suggest an efficient ant colony optimisation algorithm for finding an ideal origin route for each specific node.