# A Survey on Energy Drainage Attacks and Countermeasures in Wireless Sensor Networks
## 5 Open Research Challenges and Discussion  
In a previous section, we reviewed state-of-the-art research in energy drain attacks and their countermeasures. Although numerous papers have been studied, some issues and research challenges remain. * New network architecture: Most of the previous studies have been conducted in distributed systems, either flat or clustering. However, many schemes exhibit high computational costs and communication overheads when detecting several attacks. To address this problem, a centralized approach was proposed using software-defined WSNs (SDWSNs) supported by cloud computing. For example, [PERSON] et al. [91] proposed security issues for the sensor-cloud architecture from various security attacks to preserve its integrity. [PERSON] et al. [92] proposed a software-defined security framework to combine intrusion prevention and anomaly detection systems. Moreover, [PERSON] et al. [93] discussed the security problem under SDWSNs. The authors proved that the edge gateway isolates the abnormal nodes and generates control messages to rapidly recover the network. However, challenges related to the failure of the controller in SDWSNs and communication overhead remain. Related to SDWSNs, as addressed in [94], centralized and resource-aware properties in SDWSNs can accommodate complex ML algorithms properly. The new ML-SDWSN architecture comprises the three SDN planes and a machine learning module. Usually, the ML module is installed in two locations: the control plane and the application plane. However, this SDN architecture is also vulnerable to security attacks. So, countermeasures for attacks are as follows [95]: forged traffic flows, attacks on the control plane, vulnerabilities in controllers, administrative station attacks, and a lack of trusted resources. Furthermore, SDN-Edge architecture [96] is also recently proposed for WSN-enabled IoT. Since the centralized controller becomes a prime target for attacks, resource-rich edge computing for SDN can contribute to improving the mitigation technique and reduce complexity. This approach can be extended to SDWSNs to improve their performance. * Cross-layered approach: Even though there has been no recent cross-layered approach for energy drain attacks in WSN since 2019, we can estimate the impact of the cross layered approach by referring to other work. [PERSON] et al. [97] discussed multi-layered security approaches and suggested how to enhance the energy efficiency of resource-constrained devices in IoT networks. As an example of secure routing, it has been proven that network performance can be preserved while energy consumption is decreased across all these layers. As an instance for energy drain attacks, jamming detection at the physical layer can be delivered to the network layer so it can be used to avoid this node to be included in the routing path in the network layer. * Integrating with the IoT: The IoT can be incorporated into WSNs to extend their communication capabilities. This result implies that most WSN technologies can be applied to the IoT. However, severe constraints in the IoT require existing schemes for WSNs to be lightweight. For example, [PERSON] et al. [98] demonstrated the feasibility of the mitigation scheme for the DoS attack in time-limited critical scenarios and large-scale IoT-based WSNs. Furthermore, [PERSON] and [PERSON] [99] proposed secure data aggregation by detecting node behavior in the network, calculating the nodes' trust value, and using a data gathering method. The proposed protocol provides a lightweight XOR-based encryption solution for securing data in a multi-hop environment and forwarding data for IoT WSNs. Practical applications and attack scenarios that involve the integration of the IoT in WSNs remain research challenges. * Using a blockchain: Conventional identity authentication protocols that depend on trusted third parties to prevent several attacks face problems in terms of additional overhead and single-point failure.