101
to 65535, but only port numbers 0 to 1023 are reserved for privileged services and are
designated as “well-known ports”. The registered ports are numbered from 1024 through
49151. The remaining ports, referred to as dynamic ports, or private ports, are numbered
from 49152 through 65535.
Examples of well-known and registered port numbers are shown below, for further
information, please see IANA’s website at: http://www.iana.org/assignments/port-numbers
For help on determining which private port numbers are used by common applications on
this list, please see the FAQs (Frequently Asked Questions) at: http://www.billion.com
Well-known and Registered Ports
Port Number Protocol Description
20 TCP FTP Data
21 TCP FTP Control
22 TCP & UDP SSH Remote Login Protocol
23 TCP Telnet
25 TCP SMTP (Simple Mail Transfer Protocol)
53 TCP & UDP DNS (Domain Name Server)
69 UDP TFTP (Trivial File Transfer Protocol)
80 TCP World Wide Web HTTP
110 TCP POP3 (Post Office Protocol Version 3)
119 TCP NEWS (Network News Transfer Protocol)
123 UDP NTP (Network Time Protocol)
161 TCP SNMP
443 TCP & UDP HTTPS
1503 TCP T.120
1720 TCP H.323
4000 TCP ICQ
7070 UDP RealAudio