B
B
Appendix B
Well Known Port Numbers
Listed below are Well Known Port Numbers that may cause network problems if they are assigned
to an NPort serial port. Refer to RFC 1700 for Well Known Port Numbers or refer to the following
introduction from IANA.
The port numbers are divided into three ranges: Well Known Ports, Registered Ports, and Dynamic
and/or Private Ports.
y
Well Known Ports
range from 0 through 1023.
y
Registered Ports
range from 1024 through 49151.
y
Dynamic
and/or
Private Ports
range from 49152 through 65535.
The Well Known Ports are assigned by IANA, and on most systems, can only be used by system
processes or by programs executed by privileged users. The following table shows famous port
numbers among the well-known port numbers. For more details, please visit the IANA website at
http://www.iana.org/assignments/port-numbers.
TCP Socket
Application Service
0 reserved
1
TCP Port Service Multiplexor
2 Management
Utility
7 Echo
9 Discard
11 Active
Users
(systat)
13 Daytime
15 Netstat
20
FTP data port
21
FTP CONTROL port
23 Telnet
25
Simple Mail Transfer Protocol (SMTP)
37
Time (Time Server)
42
Host name server (names server)
43 Whois
(nickname)
49
Login Host Protocol (Login)
53
Domain Name Server (domain)
79 Finger
protocol
(Finger)
80
World Wide Web HTTP
119
Network News Transfer Protocol (NNTP)
123
Network Time Protocol
213 IPX
160 to 223
Reserved for future use
