Network Toolkit - Probe
| Common Ports | |
| 21 | FTP Server |
| 22 | SSH |
| 23 | Telnet Server |
| 25 | Mail (SMTP) Server |
| 53 | DNS Server |
| 80 | Web (HTTP) Server |
| 110 | Mail (POP3) Server |
| 443 | SHTML (Secure Web) Server |
| 1433 | MS SQL Server |
| 3128 | Squid Proxy Server |
| 3306 | MySQL Server |
| 3389 | Microsoft Terminal Services (Remote Desktop) |
| 5000 | Universal Plug and Play |
| 6660-6669 | IRC Servers |
| 6881-6900 | Older BitTorrent clients |