Victor works as a professional Ethical Hacker for SecureEnet Inc. He wants to scan the wireless network of the company. He uses a tool that is a free open-source utility for network exploration. The…

Nessus is a commercial vulnerability scanner that performs credentialed and uncredentialed audits against known CVEs; it does not primarily rely on raw IP packets for the broad host and port discovery described.

Kismet is a passive wireless network detector and packet sniffer focused on 802.11 wireless traffic, and does not actively send raw IP packets to probe hosts, enumerate ports, or perform OS fingerprinting.

Nmap (Network Mapper) is explicitly described in its official documentation as a free, open-source utility for network exploration and security auditing that uses raw IP packets to discover hosts, open ports, running services with version detection, operating system fingerprinting, and firewall/filter identification. This matches every capability listed in the question exactly, making it the definitive answer.

A Sniffer passively captures traffic on a network segment but does not actively send raw IP packets to probe hosts, enumerate open ports, or detect operating systems or firewall configurations.