Network Scanning and Enumeration Questions

Covers the active reconnaissance phase in which testers discover live systems, identify open ports and protocols, enumerate running services and versions, and detect operating system characteristics to build a target inventory and inform further testing. Includes practical techniques and concepts for port scanning (for example, TCP connect, TCP SYN, UDP scans), timing and stealth considerations, handling false positives and network noise, and strategies for large network sweeps. Also covers tool usage with emphasis on Nmap: host discovery, port and service detection, service version enumeration, operating system fingerprinting, and the Nmap Scripting Engine for automated checks and vulnerability discovery. Finally, it covers how to interpret scan output, correlate results across tools, prioritize targets, and plan subsequent exploitation or validation steps while maintaining legal and ethical testing practices.