Multiple Servers Behind Sua - ZyXEL Communications Prestige 314 User Manual

P314 Broadband Sharing Gateway with 4-Port Switch
When SUA is disabled, the Prestige sends packets from your LAN computers to the remote computer on the
WAN using real source and destination IPs - no port translation is performed. If the LAN computers use
private IPs (Private Networks IPs: 10.0.0.0 ~ 10.255.255.255; 172.16.0.0. ~ 172.31.255.255; 192.168.0.0. ~
192.168.255.255) and SUA is disabled, outgoing packets are routed by the Prestige but are never returned.
Only legal IPs are valid on the Internet. Computers on your LAN must use legal IPs
when SUA is disabled.
6.2

Multiple Servers behind SUA

If you wish, you can make inside servers for different services, e.g., web or FTP, visible to the outside users,
even though SUA makes your whole inside network appear as a single machine to the outside world. A
service is identified by the port number, e.g., web service is on port 80 and FTP on port 21.
As an example, if you have a web server at 192.168.1.2 and an FTP server 192.168.1.3, then you need to
specify for port 80 (web) the server at IP address 192.168.1.2 and for port 21 (FTP) another at IP address
192.168.1.3.
Please note that a server can support more than one service, e.g., a server can provide both FTP and DNS
service, while another provides only web service. Also, since you need to specify the IP address of a server
in the Prestige, a server must have a fixed IP address and not be a DHCP client whose IP address potentially
changes each time it is powered on.
In addition to the servers for specific services, SUA supports a default server. A service request that does not
have a server explicitly designated for it is forwarded to the default server. If the default server is not
defined, the service request is simply discarded.
To make a server visible to the outside world, specify the port number of the service and the inside IP address
of the server in Menu 15, Multiple Server Configuration.
Please note that the default filters protect the services running on the P314 (web, telnet, ftp, etc). These
services are NOT protected by the SUA! Moreover, SUA protection is compromised once servers are
specified in menu 15.
SUA Server Setup 6-3