Dive into the world of port scanning: Explore techniques, tools, and Visualization simulations.
Port scanning is a method for determining which ports on a network are open and could be receiving or sending data. It is often used by administrators to verify security policies of their networks and by attackers to identify running services on a host with the view to compromise it.
Attempts to complete a full TCP three-way handshake (SYN - SYN ACK - ACK) with each port.
Sends a SYN packet and analyzes the response without completing the handshake. Same as TCP but without the final ACK packet.
Sends UDP packets to identify open UDP ports. If the port is close ICMP Destination Unreachable (Type 3, Code 3) response indicating that the port is closed. If the port is open, no response (no ICMP error) or the service processes the request and replies
Sends a FIN packet to elicit a response from closed ports. If the port is open, the packet is ignored and no response is sent. If the port is closed, the system will respond with an RST packet.
Sends packets with FIN, URG, and PUSH flags set. If the port is open, the system will ignore the packet and not respond. If the port is closed, the system will respond with an RST packet.
Scan all ports on the specified IP address
nmap -p- 192.168.1.1Perform a SYN scan on the default 1000 ports
nmap -sS 192.168.1.1Perform a UDP scan on specified ports
nmap -sU -p 123,161,500 192.168.1.1Attempt to determine service/version info for open ports
nmap -sV 192.168.1.1Scan ports 1-1000 on the specified IP address
nc -zv 192.168.1.1 1-1000