ZyXEL Communications G-2000 Plus User Manual

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ZyAIR G-2000 Plus User’s Guide
Chapter 10 Single User Account (SUA) / Network Address Translation (NAT)
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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
PORT NUMBER
ECHO
7
FTP (File Transfer Protocol)
21
SMTP (Simple Mail Transfer Protocol)
25
DNS (Domain Name System)
53
Finger
79
HTTP (Hyper Text Transfer protocol or WWW, Web)
80
POP3 (Post Office Protocol)
110
NNTP (Network News Transport Protocol)
119
SNMP (Simple Network Management Protocol)
161
SNMP trap
162
PPTP (Point-to-Point Tunneling Protocol)
1723
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