## 7 Conclusions  
In this paper, we presented an optimized transmission scheme for enhancing security and reliability in a diamond untrusted relay network using cooperative jamming and LF relaying. Our approach addresses the challenge of secure data transmission in scenarios involving untrusted relays by balancing power allocation between the source, relays, and destination. The introduced RSP metric provides a robust evaluation of the system's performance. Our results demonstrate that optimal power distribution significantly improves RSP, ensuring that the destination can accurately retrieve the original message while maintaining its confidentiality from untrusted relays. Future research could extend this framework to networks with multiple sources and multiple untrusted relays, further strengthening secure communication strategies in complex relay environments. This analysis underscores the importance of balanced power allocation in achieving maximum RSP, providing valuable insights for designing efficient and secure communication systems under jamming conditions. To extend the proposed framework to multi-source networks, several key considerations must be addressed. The primary challenge involves managing inter-source interference, which could degrade both the reliability and security of communications. Advanced strategies such as interference alignment and cooperative beamforming could mitigate these effects. Additionally, cooperative strategies among sources, such as coordinated jamming and shared CSI, could enhance overall network performance. The RSP metric could also be generalized to account for the interactions between multiple sources, requiring new analytical approaches. As the complexity of the network increases, scalable algorithms like decentralized optimization or machine learning-based techniques may be necessary to manage the problem's dimensionality. By addressing these challenges, the framework could be effectively adapted to multi-source networks, enabling its application to more complex and dynamic communication environments, such as IoT systems and vehicular  
Figure 7: Secure and reliable probabilities with different power allocation ratio combinations with \(a\) and \(b\). The vertical lines represent the points at which the secure and reliable probabilities are maximized. networks. Future research will explore these extensions, aiming to validate the framework's robustness and scalability in multi-source scenarios. While the primary focus of this paper is on the theoretical foundations and simulation-based validation of the proposed optimization framework, it is essential to consider the practical challenges associated with implementing these strategies in real-world communication systems. The hardware requirements for cooperative jamming, for instance, would necessitate advanced transceivers capable of generating and managing jamming signals without introducing excessive interference to legitimate communications. Furthermore, the feasibility of the proposed power allocation strategies in dynamic environments, such as mobile networks, must account for the rapidly changing channel conditions and the need for real-time adaptability. This could involve the development of adaptive algorithms that can quickly adjust power levels based on instantaneous channel state information. Additionally, potential latency issues, particularly in time-sensitive applications, must be carefully managed to ensure that the security and reliability enhancements do not come at the cost of increased delay. Addressing these practical considerations is critical for the successful deployment of the proposed framework in real-world scenarios, and these aspects will be explored in greater detail in our future work. Conceptualization, S.Q. and M.C. ; methodology, S.Q. ; software, S.Q. ; validation, S.Q. and M.C. ; formal analysis, S.Q. ; investigation, S.Q. ; resources, S.Q. ; data curation, S.Q. ; writing--original draft preparation, S.Q. and M.C. ; writing--review and editing, S.Q. and M.C. ; visualization, S.Q.