A port is a communication endpoint in a network that allows a computer to distinguish between different kinds of traffic and services, identified by a number, enabling data to be sent to the correct application. A protocol is a set of rules that computers follow to communicate with each other over a network.
Understanding TCP/IP ports and protocols is crucial in networking. These protocols facilitate communication between devices over the internet and local networks. Each protocol uses specific port numbers to ensure data reaches the correct destination. This article explains common TCP/IP ports and protocols, describing their basic functions in simple terms.
TCP/IP Ports and Protocols
Here is the list of common TCP/IP ports and protocol works on that.
| Protocol | TCP/UDP | Ports | Description |
|---|---|---|---|
| FTP | TCP | 20/21 | Used for transferring files between computers. Port 21 is used for making connection with server and Port 20 is used for transferring data |
| Telnet | TCP | 23 | In earlier time it was used for remote login, not secure. |
| SMTP | TCP | 25 | Used for sending emails. |
| DNS | UDP | 53 | DNS (Domain Name System) translates human-readable domain names (like www.example.com) into IP addresses that computers use to identify each other on the network. |
| DHCP | UDP | 67/68 | Used to assign IP addresses to devices on a network. |
| TFTP | UDP | 69 | Used for simple file transfers. |
| HTTP | TCP | 80 | Used for web pages and websites. |
| POP3 | TCP | 110 | Used for downloading emails to your computer. |
| NTP | UDP | 123 | Used to synchronize clocks on networked devices. |
| IMAP | TCP | 143 | Used for reading emails on a mail server. |
| SNMP | UDP | 161/162 | Used for network management and monitoring. |
| LDAP | TCP | 389 | Used for accessing and maintaining directory services. |
| HTTPS | TCP | 443 | Used for secure web pages and websites. |
| SMB | TCP | 445 | Used for file sharing in Windows networks. |
| SMTPS | TCP | 465 | Used for sending emails securely. |
| LDAPS | TCP | 636 | Used for secure access to directory services. |
| BIND | TCP | 953 | Used for controlling DNS server operations. |
| FTPS | TCP | 989/990 | Used for secure file transfers. |
| IMAPS | TCP | 993 | Used for secure email retrieval on a mail server. |
| POP3S | TCP | 995 | Used for secure email downloading. |
| RDP | TCP | 3389 | Used for remote desktop access. |
Summary
Knowing about TCP/IP ports and protocols helps in understanding how different network services operate. Web browsing (HTTP and HTTPS), email communication (SMTP, IMAP, POP3), and many other services rely on specific protocols. By learning about these functions and their associated port numbers, we gain a clearer understanding of how data travels across networks, ensuring efficient and secure communication.
