🌐 1. Understanding Network Fundamentals Before defending a network, you must understand how it works. Key Concepts: IP Addressing (IPv4/IPv6): Unique identifiers for devices. Subnetting: Dividing a large network into smaller segments for efficiency and security. MAC Address: Hardware-level address identifying devices on a LAN. Ports & Protocols: Each service communicates using a specific port (e.g., HTTP → port 80, HTTPS → 443). OSI & TCP/IP Models: Frameworks describing how data moves through