ZyXEL Communications Prestige 792H, User Manual

Page: 99 / 437

Prestige 792H User’s Guide
NAT 6-5
6.3 SUA Server
A SUA server set is a list of inside (behind NAT on the LAN) servers, for example, web or FTP, that you can
make visible to the outside world even though SUA makes your whole inside network appear as a single
computer to the outside world.
You may enter a single port number or a range of port numbers to be forwarded, and the local IP address of
the desired server. The port number identifies a service; for example, web service is on port 80 and FTP on
port 21. In some cases, such as for unknown services or where one server can support more than one service
(for example both FTP and web service), it might be better to specify a range of port numbers. You can
allocate a server IP address that corresponds to a port or a range of ports.
Many residential broadband ISP accounts do not allow you to run any server processes (such as a Web or
FTP server) from your location. Your ISP may periodically check for servers and may suspend your account
if it discovers any active services at your location. If you are unsure, refer to your ISP.
Default Server IP Address
In addition to the servers for specified services, NAT supports a default server IP address. A default server
receives packets from ports that are not specified in this screen.
If you do not assign an IP address in Server Set 1 (default server), the Prestige
discards all packets received for ports that are not specified here or in the remote
management setup.
6.3.1 Port Forwarding: Services and Port Numbers
A NAT server set is a list of inside (behind NAT on the LAN) servers, for example, web or FTP, that you can
make accessible to the outside world even though NAT makes your whole inside network appear as a single
machine to the outside world.
Use the
SUA Server page to forward incoming service requests to the server(s) on your local network. You
may enter a single port number or a range of port numbers to be forwarded, and the local IP address of the
desired server. The port number identifies a service; for example, web service is on port 80 and FTP on port
21. In some cases, such as for unknown services or where one server can support more than one service (for
example both FTP and web service), it might be better to specify a range of port numbers.
In addition to the servers for specified services, NAT 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 is not defined,
the service request is simply discarded.
Many residential broadband ISP accounts do not allow you to run any server
processes (such as a Web or FTP server) from your location. Your ISP may
periodically check for servers and may suspend your account if it discovers any
active services at your location. If you are unsure, refer to your ISP.