Communication networks are the backbone of today’s interconnected world, supporting everything from basic information exchange to the operation of critical infrastructures. As these systems continue to grow in complexity and importance, ensuring their security, integrity, and reliability has become a top priority for both governments and industry. In this talk, we examine how artificial intelligence (AI)—particularly machine learning and data-driven techniques—is being applied to network security at the transport and network layers. We will discuss current methodologies, enabling technologies, and the persistent technical and scientific challenges. Particular attention will be given to emerging paradigms such as deep learning and generative AI, with a critical analysis of the factors limiting their practical impact on threat detection and mitigation.