The most often used port numbers are shown in the following table. Please refer to RFC 1700
for further information about port numbers. Please also refer to the Supporting CD for more
examples and details on SUA/NAT.
Table 43 Services and Port Numbers
SERVICES
ECHO
FTP (File Transfer Protocol)
SMTP (Simple Mail Transfer Protocol)
DNS (Domain Name System)
Finger
HTTP (Hyper Text Transfer protocol or WWW, Web)
POP3 (Post Office Protocol)
NNTP (Network News Transport Protocol)
SNMP (Simple Network Management Protocol)
SNMP trap
PPTP (Point-to-Point Tunneling Protocol)
10.3.3 Configuring Servers Behind SUA (Example)
Let's say you want to assign ports 21-25 to one FTP, Telnet and SMTP server (A in the
example), port 80 to another (B in the example) and assign a default server IP address of
192.168.1.35 to a third (C in the example). You assign the LAN IP addresses and the ISP
assigns the WAN IP address. The NAT network appears as a single host on the Internet
Chapter 10 Single User Account (SUA) / Network Address Translation (NAT)
ZyAIR G-2000 Plus User's Guide
PORT NUMBER
7
21
25
53
79
80
110
119
161
162
1723
142