IoT security needs to be strengthened as smart homes are more connected and prone to complex cyberattacks. One innovative approach to identify and lower negative behavior in IoT networks is prestige-based connection monitoring. However, by having restricted scalability, poor trust assessment, and vulnerability to node impersonation or penetration, existing methods might threaten the integrity of the network. This work proposes a Blockchain-based Reputation System (BC-RS) based dynamic and transparent node trust assessment to tackle these limits in order to avoid hostile node infiltration in smart home networks. By use of distributed ledgers, the BC-RS system assures tamper-proof integrity of reputation data, computes trust ratings, and records node interactions. The proposed method monitors node behavior, finds real-time harmful activity, and prevents untrusted nodes from network connection. Experimental analysis shows that the framework enhances network security by increasing trust score accuracy by 98.2%, reducing false positives in threat detection by 39%, and improving system resilience by 97.6%. These findings confirm the effectiveness of prestige-based tracking combined with blockchain in strengthening IoT security and ensuring safer smart home environments.

IoT Security, Blockchain, Reputation System, Smart Home, Malicious Node Detection, Trust Evaluation.