# Data Security-Based Routing in MANETs Using Key Management Mechanism
## 1 Introduction  
Mobile Ad Hoc Networks (MANETs) are autonomous networks developed using wireless mobile nodes without the support of any kind of infrastructure. In a MANET, nodes can communicate with each other freely and dynamically through radio frequencies [1, 2, 3]. MANETs allow mobile users to communicate with one another when permanent infrastructure is not available or possible [4]. The routes in a MANET are frequently unable to work correctly due to external noise, transmission interference, and mobility. The development of the internet in recent years has considerably improved MANETs' usage in various critical applications. Recently, MANETs are extensively utilized to build Internet of Things (IoT)-based smart networks [5, 6]. As a result, the requirements for safety and consistency in these types of networks should be thoroughly re-evaluated. Due to a limited transmission range, nodes communicate with each other using multiple hops [7]. Thus, the availability of every node is equally important. Therefore, an efficient routing protocol is required to evaluate an optimal path between the source and sink. While developing a MANET, many routing protocols based on trust were suggested and evaluated. Most trusted management plans were built for cooperative routing todetect the self-destructive nodes caused by erroneous nodes. When developing safer route protocols, researchers have considered reputations and links about mobile nodes, among other things. Various predicted route models were also designed, which were used to quantitatively identify distinct types of security assaults. Some researchers discussed the issues related to key problems associated with the IoT-based MANETs. Various security and vulnerability risks were considered during the design of protocols [8,9]. The routing protocols can be categorized as reactive, proactive, and hybrid. The proactive routing protocols, such as the Destination Sequence Distance Vector (DSDV) [10], need periodic updates of the routing tables. Thus, a huge number of control packets are generated. Hence, these protocols were found to be unsuitable for MANETs. Therefore, reactive protocols, such as ad hoc on-demand distance vector routing (AODV) [11] and dynamic source routing (DSR) [12], were designed. A path is developed between the source and sink whenever it is required. These protocols utilize two steps, i.e., route discovery and route maintenance. Routes are computed using a route-discovery process. A source node utilizes a route-maintenance step to evaluate any changes in topology. To secure communication among MANET nodes, various cryptography-based protocols have been proposed. Some well-known protocols are Efficient Node Admission and Certificateless Secure Communication (ENACSC) [13], Anonymous Location-Aided Routing (ALARM) [14], Energy-Efficient Partial Permutation Encryption (EEPPM) [15], Friend-Based Ad Hoc Routing to Establish Security (FACES) [16], Anonymous Multipath Routing Protocol (AMRP) [17], Statistical Traffic Pattern-Discovery System (STARS) [18], and Non-Interactive Self-Certification (NSC) [19]. However, these protocols are prone to various security threats and also consume more energy from the nodes. In [20], a trust-based approach with efficient predictability for MANETs on the IoT was designed; it estimates the last node value based on direct and indirect information judgments and a sense of trust. In [21], an energy consumption system was designed for MANETs on the IoT that was based on ant colony optimization. Ant colonies were used to minimize the end-to-end delay. Recently, many secure and energy-aware multipath routing protocols have been designed for MANETs, such as the Trust Aware Secure Energy Efficient Hybrid Protocol (TASEEHP) [22], Hybrid Secure Multipath Routing Protocol (HSMRP) [23], Signcryption Technique (ST) [24], and Recurrent Reward-Based Learning (RRBL) [25]. These protocols have shown remarkable performance against various security threats.