Before You Touch Nmap: Networking Fundamentals Every Beginner Must Understand Before you run a single Nmap command, you need to understand how networks actually work. Nmap is not magic — it is a …

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A beginner-focused primer on networking fundamentals required before using Nmap. Covers the OSI model, IP addressing, TCP vs UDP protocols, the TCP 3-way handshake, TCP control flags (SYN, ACK, FIN, RST, PSH, URG), TCP header fields, port ranges, and why these concepts matter when interpreting Nmap scan results. Explains how firewalls, IDS/IPS, NAT, and rate limiting affect scan behavior. Part 1 of a structured series leading up to practical Nmap usage.

Before You Touch Nmap: Networking Fundamentals Every Beginner Must Understand

The Transport Layer (Layer 4) — TCP vs UDP