Definition - What does Port Scanner mean?
A port scanner refers to a software application program that scans a server for open ports. It enables auditors and network administrators to examine network security while attackers and hackers use it to identify open ports for exploiting and/or running malicious services on a host computer or server.
Port scanners are primarily used by network security administrators to scan and monitor network ports on a system, server or IT environment.
Techopedia explains Port Scanner
Port scanners work by attempting to connect to all or a set of predefined ports on a system that provides network or application access. Depending on the capabilities of the port scanner or scan requirements, a port scanner may have several operation modes including:
- Vanilla: Probes and scans all ports on a system/server.
- Strobe: Only selected ports are scanned or probed.
- UDP: Scans for open UDP ports.
- Sweep: A similar port number is probed on more than one computer.
Although a port scanner is designed to aid network administrators in strengthening security, if used unethically by hackers it can reveal open ports that could be exploited.