## 4 Performance Evaluation
### Results and Discussion
Unlike other solutions that cannot cope with secret generation and distribution only with the authorized nodes, the RNM-SC approach uses the Blum-Goldwasser cryptosystem to avoid malicious entries and increase the packet delivery performance from medical sensors to the cloud servers. Figure 6 illustrates the performance evaluation of the RNM-SC approach in terms of end-to-end delay against existing work. It was noticed that with the increase in jamming nodes, the interval of data delay also increased. This is due to the flooding of malicious packets and depletion of the nodes' energy with unnecessary processing. However, the tested results showed that the proposed approach improves the evaluation of end-to-end delay by 14%, and 22%, respectively, in the comparison with existing solutions. It is due to the use of the bidirectional searching technique in exploring the shortest and least risky route from the source node towards a destination. It executes two concurrent searches, i.e., one from the medical sensor to a cloud system and one that operates in reverse condition from the cloud system. It is seen from the experiments' analysis that the existing solution causes most of the route failures, and as a result, most of the time is wasted in route re-construction. Such practice is avoided in the RNM-SC approach by increasing the route stability period based on heuristic function, and as a result, the fraction of end-to-end delay is minimized by decreasing the chances of route re-generation from the initial to the goal node. Additionally, with the mutual authentication of the medical sensors based on  
Figure 4: Energy consumption and jamming nodes. private-public keys, the RNM-SC approach declines the false route request packet from the malicious node, and ultimately offers on-time healthcare data transmissions. In Figure 7, the tested results of the RNM-SC approach are compared with an existing solution in terms of routing complexity. The routing complexity increases with the additional overhead of jamming nodes and imposes an unnecessary packet drop ratio. However, analysis of the results demonstrates that the RNM-SC approach significantly decreases routing complexity by 32% and 43%, respectively, compared to other solutions. This is because it imposes the lowest manageable processing costs in finding the medical forwarders to the cloud using a heuristic function in terms of distance, link risk, and nodes' trust. Furthermore, the bidirectional search technique decreases the complexity and determines the optimal routes towards cloud servers in a fraction of time with lower overhead. Unlike other solutions that impose extra control overhead packets while applying security on observing data, our proposed RNM-SC approach iteratively performs data encryption among h least significant bits and secret keys using lightweight XoR operation and also minimizes the overhead on the medical sensors and contributes to network performance. Figure 5: Packet drop ratio and jamming nodes. Figure 6: End-to-end delay and jamming nodes. In Figure 8, the tested results of the RNM-SC approach are compared to other solutions in the presence of jamming nodes. It is seen that with increasing numbers of jamming nodes, the ratio of tampered packets also increases. However, the experimental results show that the RNM-SC approach significantly decreased the ratio of tampered packets by 33% and 40%, respectively, compared to the other solutions due to the incorporation of security and authentication algorithms. The proposed approach can tackle malicious objects and achieve reliable forwarding of sensor data even if links are overloaded by malicious packets. Furthermore, the secured cloud model provides trusted communication among cloud systems and connected users with a hybrid mechanism. The proposed security strategy offers an efficient minimum of computing power to analyze the tampered packets and avoid malicious events that disrupt system performance in terms of privacy, authentication, and data integrity.