# An Asymmetric Encryption-Based Key Distribution Method for Wireless Sensor Networks
## 1 Introduction  
Wireless sensor networks (WSNs) have been proven to be suitable for large numbers of applications, ranging from industry and security domains, such as environment monitoring, fire detection and precision agriculture, to personal use, like health supervision. WSNs are composed of a large number of sensors that work independently of each other. These sensors transmit routing information to each other and forward collected application data [1, 2]. The major weakness of wireless sensor networks lies in the limitations of resources, including memory, battery capacity, data processing, and communication capabilities. Sensors and wireless channels are vulnerable to eavesdropping, physical interception, malicious attacks, message tampering, identity impersonation, and side channel attacks [3, 4, 5], and the presence of important and sensitive information in the network increases the importance of security issues. Therefore, one of the focuses of wireless sensor network research is understanding how to provide high confidentiality for the transmitted application data and control messages to prevent various illegal attacks [6, 7, 8, 9]. At present, it is generally believed that encryption is a key technology that can provide confidentiality between the cloud and the end [10, 11, 12], which can also be used in WSNs' data exchange. Over the years, many researchers have proposed schemes to enhance the security of wireless sensor networks. The (p, q)-Lucas polynomial-based key management scheme for WSN was proposed by [PERSON] et al. [13]. Their scheme outperforms other polynomials in terms of the number of keys used and efficiency. [PERSON] proposed a dynamic key management scheme for the clustered sensor network that supports the addition of new nodes into the network [14]. The proposed scheme has shown low energy consumption and good resiliency against node capture attacks. [PERSON] et al. [15] proposed an ECDH (elliptic-curve Diffie-Hellman)-based authentication and key agreement protocol forWSN infrastructure. The proposed protocol supports the dynamic node addition in WSN environments and uses a strong ECDH technique to generate unique symmetric and session keys for each session. The authors of [16] proposed a trust-based multipath routing protocol called TBSMR, which improved the QoS and overall performance of MANETs in cellular networks through congestion control, packet loss reduction, malicious node detection, and secure data transmission. These proposals differ from the scheme proposed in this paper as TBSMR achieves power savings from the perspective of optimized routing protocols. In MANET-based medical systems, to achieve secure communication, a logic graph-based key generation scheme hybrid and encryption scheme is proposed by [PERSON] [17], which provides high security for MANET medical networks, as well as less computational power and shorter encryption time. In 2018, [PERSON] et al. proposed an authentication scheme for multimedia communications that was designed for an IoT environment base on WSNs [18]. [PERSON] et al. [19] designed a lightweight authentication scheme for WSNs. It addressed the common security requirements and user untraceability issues. To ensure confidentiality and security in IOT, a biometric-based authentication and key agreement protocol are proposed for wireless sensor networks [20]. In recent years, researchers have produced several more viable authentication protocols and key agreements in the field of wireless sensor network security. [PERSON] et al. [21] proposed a lightweight multiple shared key agreement based on the hyper-elliptic-curve Diffie-Hellman method. The protocol decreases keys exchange overhead and increases the safety of the keys. In response to the security weaknesses of the scheme in [22], [PERSON], S. proposed a lightweight authentication based on the three-factor technique and key agreement protocol for WSN [23]. The proposed scheme addressed several security requirements and used XOR and hash functions.