Existing DER gateways were designed for remote monitoring and control of inverters, but lack dedicated security features. To counter the risk of cyberattacks via the internet, it's necessary to implement separate cybersecurity facilities and detection systems. It creates a significant cost burden for both grid operators and power generation companies. The Security-enhanced DER Monitoring Device (SDMD) addresses this issue. It detects and blocks data tampering between internet-connected power generation resources and the grid with 99.9% accuracy. Furthermore, it uses strong, hardware-based authentication to prevent unauthorized devices from connecting with 100% certainty. By strengthening the security of distributed energy systems, the SDMD helps prevent large-scale blackouts caused by cyberattacks. This product not only addresses the security vulnerabilities in the rapidly growing renewable energy infrastructure but also plays a key role in building a reliable national energy grid and achieving carbon neutrality goals.