## 2 Related Work
Thus, every time the network topology or target area conditions change, the routing optimization and location parameters must be reevaluated, and accordingly, all sensor nodes must be reprogrammed, which is highly impractical. Furthermore, in SRTLD, the authors also assume that the sink node must be a trusted computing base. [PERSON] _et al._[29] presented ESPA for WSNs with the goal of ensuring the authenticity and integrity of sensed data. The mechanism presented by [PERSON] _et al._[29] depends on shared secret keys and one-way hash functions. The shared key is known by the sensor nodes and the base station. The authors proposed a general ant colony optimization (ACO)-based energy-aware routing (DEAR) algorithm. The routing decision depends on two metrics related to the distance and remaining battery power of the nodes. In presenting their security scheme, the authors assumed that the main commands are generated from a centralized location, that is, the base station or a gateway. The general ACO architecture depends on ACO_forward (ACO_F) travel from the source to the destination and ACO_backward (ACO_B) travel back from the destination to the source. This generates massive traffic overhead and causes the network to consume an enormous amount of energy. In a WSN scenario in which the network contains a large number of wireless sensor nodes that communicate in a multi-hop manner, feedback (ACO_B) is practically impossible. In addition, if the shared key information has not been shared with a particular node, then that wireless sensor node may be prohibited from participating in the network and any communications therein; consequently, the entire network could collapse at any time. [PERSON] _et al._[29] analyzed the performance of ESPA in terms of three defense parameters (anonymity, confidentiality, and integrity) and compared energy-efficient ant-based routing algorithm (EEABR), secure energy-efficient routing protocol (SERP) and energy-efficient secure pattern based data aggregation (ESPDA) using MATLAB software. The authors claimed that ESPA performs better than the SERP and ESPDA methods. In [33], the authors proposed a scheme called Extended Two-hop Keys Establishment (ETKE) to protect the hop count information without referring to the sink node. Furthermore, the authors proposed a novel secure routing protocol named Secure Multi-pAths Routing for wireless sensor neTworks (SMART) based on the ETKE key management scheme. The authors claimed that SMART is resilient against forged hop count attacks and outperforms SeRINS in terms of energy consumption. The authors of [34; 35] proposed BIOARP, which employs enhanced ant colony optimization (eACO) [36] to select optimal routes from a source node to a destination node in a WSN. BIOARP provides a self-optimized routing mechanism that enables improved data throughput, extends the WSN lifetime and minimizes delays with less data loss. [PERSON] _et al._[23] also proposed BIOSARP, an enhanced version of BIOARP, by adding a self-security management module that relies on an AIS. The ability of BIOSARP to detect, classify, and remove non-self nodes is analogous to the human immune system (HIS) because the AIS is a derivation of the HIS in the computer domain. The primary function of the HIS is the detection of abnormalities by distinguishing between self and non-self entities. Analogously, the primary function of BIOSARP is to detect attacks and classify self and non-self nodes. The major limitation of BIOSARP is that it requires time to develop the knowledge of the overall network during the initialization phase of WSN deployment. The initialization phase is a critical period during the complete lifespan of a WSN and requires efficient and active security measures. When nodes are deployed, they must acquire and/or build information regarding their neighboring nodes and the environment to enable them to communicate and transfer data to the destination.