ZyXEL Communications 10 User Manual
Page 157
ZyWALL 10~100 Series Internet Security Gateway
NAT
12-15
Table 12-7 Services & Port Numbers
SERVICES
PORT NUMBER
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
12.4.1 Configuring a Server behind NAT
Follow these steps to configure a server behind NAT:
Step 1.
Enter 15 in the main menu to go to Menu 15 - NAT Setup.
Step 2.
Enter 2 to go to Menu 15.2 - NAT Server Setup.
Step 3.
Enter a port number in an unused Start Port No field. To forward only one port, enter it again
in the End Port No field. To specify a range of ports, enter the last port to be forwarded in the
End Port No field.
Step 4.
Enter the inside IP address of the server in the IP Address field. In the following figure, you
have a computer acting as an FTP, Telnet and SMTP server (ports 21, 23 and 25) at
192.168.1.33.
Step 5.
Press [ENTER] at the “Press ENTER to confirm …” prompt to save your configuration after
you define all the servers or press [ESC] at any time to cancel.