ZyXEL Communications 1600 User Manual
Prestige 1600 Universal Access Concentrator
9-12
NAT
Figure 9-14 Specifying an Inside Sever
9.4.3 Example 3 - General Case
In this example, there are 3 IGAs from your ISP. There are many departments but two have their own FTP server.
All departments share the same router. You want to reserve 1 IGA for each department with an FTP server and the
other IGA is used by all. You want to map the FTP servers to the first two IGAs and the other LAN traffic to the
remaining IGA. You also want to map the third IGA to an inside web server and mail server. You need to configure
4 rules as follows.
All departments share the same router. You want to reserve 1 IGA for each department with an FTP server and the
other IGA is used by all. You want to map the FTP servers to the first two IGAs and the other LAN traffic to the
remaining IGA. You also want to map the third IGA to an inside web server and mail server. You need to configure
4 rules as follows.
Rule 1.
You map the first IGA to the first inside FTP server (1: 1 mapping, giving both local and global IP
addresses).
addresses).
Rule 2.
You map the second IGA to the second inside FTP server (1: 1 mapping, giving both local and global IP
addresses).
addresses).
Rule 3.
You map all other addresses to IGA3 (Many : 1 mapping).
Rule 4.
You also use the third IGA to open the web server and mail server on the LAN. Type Server allows us
to specify a server, of a given service behind NAT.
to specify a server, of a given service behind NAT.
The situation looks somewhat like this:
Figure 9-15 NAT - Example 3
Menu 15.2 - NAT Server Sets
Port #
----
IP Address
---------------
1. (Used by SUA)
192.168.1.10
2. 0
0.0.0.0
3. 0
0.0.0.0
4. 0
0.0.0.0
5. 0
0.0.0.0
6. 0
0.0.0.0
7. 0
0.0.0.0
8. 0
0.0.0.0
9. 0
0.0.0.0
10. 0
0.0.0.0
Press ENTER to Confirm or ESC to Cancel: