Port scanning is a network security testing method used to identify open ports on a target host. By scanning ports, you can understand the target host's service types and security vulnerabilities, and take appropriate security measures.
The open port scanner is a free tool that can help you scan IP addresses and domains to detect the status of common ports and understand network security.
How to Use:
Common Port Functions:
Port21: FTP File Transfer Protocol, used to upload and download files.
Port22: SSH Secure Shell Protocol, used for remote login and secure file transfer.
Port23: Telnet Remote Login Protocol, used for remote login, but less secure, it is recommended to close.
Port25: SMTP Simple Mail Transfer Protocol, used to send emails.
Port79: Finger Protocol, used to retrieve user information, it is recommended to close.
Port80: HTTP Hypertext Transfer Protocol, used to access web pages.
Port110: POP3 Post Office Protocol, used to receive emails.
Port135: RPC Remote Procedure Call Protocol, used to remotely call programs, it is recommended to close.
Port137-139: NetBIOS Protocol, used for network naming services, it is recommended to close.
Port143: IMAP Internet Message Access Protocol, used to receive emails.
Port443: HTTPS Secure Hypertext Transfer Protocol, used for secure access to web pages.
Port445: SMB Shared File Protocol, used to share files and printers, it is recommended to close.
Port888: Web server, it is recommended to close.
Port1433: Microsoft SQL Server database server, it is recommended to close.
Port3306: MySQL database server, it is recommended to close.
Port3311-3312: MySQL database server, it is recommended to close.
Port3389: RDP Remote Desktop Protocol, used to remotely control computers, it is recommended to close.
Port8888: Web server, it is recommended to close.
Security Suggestions:
For security purposes, it is recommended that you close unnecessary ports.
You can use a firewall to block access to specific ports.
If you are unsure which ports need to be closed, please consult a professional.