Common Network Ports
A reference guide for commonly used network ports and their services.
| Port | Protocol | Service | Description | Category | Details |
|---|---|---|---|---|---|
| 20 | TCP | FTP | Used by FTP to transfer files between a client and server. | File Transfer | |
| 21 | TCP | FTP Control | Used by FTP for control commands to establish and manage the FTP session. | File Transfer | |
| 22 | TCP | SSH (Secure Shell) | Used for secure remote login and command execution over an encrypted connection. | Remote Access | |
| 23 | TCP | Telnet | Used for unencrypted remote login and command execution over a network. | Remote Login | |
| 55 | UDP/TCP | DNS (Domain Resolution) | Used for resolving domain names to IP addresses and vice versa, allowing users to access websites and services using human-readable names instead of numeric IP addresses. | Domain Name System | |
| 67 | UDP | DHCP (Server to Client) | Used by DHCP servers to assign IP addresses and network configuration to clients on a network. | Dynamic Host Configuration Protocol | |
| 68 | UDP | DHCP (Client to Server) | Used by DHCP clients to request IP addresses and network configuration from DHCP servers on a network. | Dynamic Host Configuration Protocol | |
| 69 | UDP | TFTP (Trivial File Transfer Protocol) | Used for simple file transfers without authentication, often in network booting scenarios. | File Transfer | |
| 80 | TCP | HTTP (Hypertext Transfer Protocol) | Used for unencrypted web traffic, allowing users to access websites and web applications using a web browser. | Web Services | |
| 110 | TCP | POP3 (Email Receiving) | Used for receiving email from a mail server, allowing users to download their email messages to their local device. | Email Services | |
| 123 | UDP | NTP (Network Time Protocol) | Used for synchronizing the clocks of computers over a network, ensuring accurate timekeeping across devices. | Time Synchronization | |
| 138 | UDP | NetBIOS Datagram Service | Provides connectionless communication between NetBIOS devices on a local network. It allows devices to send datagrams, browse network resources, and exchange information without establishing a session. | Network Services | |
| 143 | TCP | IMAP | Internet Message Access Protocol (IMAP) allows email clients to access and manage messages stored on a mail server without downloading them permanently to a device. | Email Services | |
| 161 | UDP | SNMP | Simple Network Management Protocol (SNMP) is used to monitor, manage, and collect information from network devices such as routers, switches, servers, printers, and access points. | Network Management | |
| 443 | TCP | HTTPS | HTTPS (Hypertext Transfer Protocol Secure) provides encrypted communication between a web browser and a web server using SSL/TLS encryption. | Web Services | |
| 445 | TCP | SMB | Server Message Block (SMB) is a network protocol used for sharing files, folders, printers, and other resources between computers on a network. | File Sharing |