103
Example: List of some well-known and registered port numbers.
The Internet Assigned Numbers Authority (IANA) is the central coordinator for the assignment of
unique parameter values for Internet protocols. Port numbers range from 0 to 65535, but only ports
numbers 0 to 1023 are reserved for privileged services and are designated as “well-known ports”
(Please refer to Table 5). The registered ports are numbered from 1024 through 49151. The
remaining ports, referred to as dynamic or private ports, are numbered from 49152 through 65535.
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
Table 5: Well-known and registered Ports
Port Number
Protocol
Description
20 TCP
FTP
Data
21 TCP
FTP
Contro
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) / SNTP (Simple
Network Time Protocol)
161 TCP
SNMP
443 TCP
&
UDP
HTTPS
1503 TCP
T.120
1720 TCP
H.323
4000 TCP
ICQ
7070 UDP
RealAudio
