# Multi-Decision Dynamic Intelligent Routing Protocol for Delay-Tolerant Networks
## 5 Discussion  
In Delay Tolerant Networks (DTN), nodes can only transmit messages through opportunistic connections, posing a challenge in effectively utilizing network resources for message forwarding. In previous protocol studies, achieving both high delivery rates and low overhead has been a difficult balance. Our protocol employs dynamic multi-decision-making, ensuring excellent performance in various network states. In Section 4, validated through simulations, the MDDI routing protocol's ability to fully utilize network resources and enhance message transmission efficiency in mobile network environments is demonstrated.  
Compared to other routing protocols introduced in Section 1, our proposed protocol has significant advantages in multiple aspects. Firstly, even in situations where network resources are limited, the MDDI routing protocol maintains high delivery rates and low latency. This protocol utilizes dynamic changes in node and a message attributes during network topology changes, ensuring outstanding performance regardless of whether the network has few nodes or experiences network congestion. Secondly, the MDDI routing protocol consistently incurs lower network overhead. In contrast to some routing protocols discussed in Part Two, which also maintain high delivery rates but generate numerous message duplicates due to flooding, the MDDI routing protocol, through multiple decision-making solutions, precisely selects the next hop for messages, ensuring message delivery to the destination node while effectively controlling the number of message duplicates.  
However, despite the numerous advantages of the MDDI routing protocol, there are potential limitations that need consideration. One potential limitation lies in the complex implementation of MDDI routing protocol attributes. Each node in the network needs to maintain four tables (two Q tables, a node attribute table, and message attribute table). In intermittent connection routing environments, these table values require real-time updates, potentially consuming significant node energy. Moreover, frequent interactions between nodes may lead to security issues, making them susceptible to attacks from malicious nodes. For instance, a malicious node might attempt to simulate another node to access its private information.  
In addition to the potential limitations discussed above, the protocol has not been widely deployed in practical networks. Implementing this protocol in real-world scenarios may face various challenges. One challenge is that the protocol might not always maintain high performance in different scenarios. For instance, in disaster and emergency rescue scenarios, historical connections among nodes might not follow strong patterns, and urgent messages should be assigned a higher security level, not solely based on encounter history. Another challenge is privacy and security. In military scenarios, selecting nodes with high trust levels for data transmission is crucial.  
Addressing these challenges requires a comprehensive consideration of the characteristics of different scenarios and flexible adjustment of the MDDI protocol's parameters and strategies. In disaster and emergency rescue scenarios, adopting more flexible message priority algorithms ensures the timely transmission of urgent messages. In military scenarios, establishing trust models, selecting trustworthy nodes for data transmission, and enhancing network encryption and identity verification measures can improve data security.  
To sum up, the introduction of the MDDI routing protocol not only underwent thorough theoretical exploration but also received validation through practical simulations. Its advantages, including high delivery rates, low latency, and minimal network overhead, make it an ideal choice in mobile network environments. These research findings not only supplement the existing knowledge base but also provide valuable insights for the development of more advanced network systems in the future.