ZyXEL Communications P-335WT - Manual (Page 147)

P-335 Series User’s Guide
Chapter 9 Network Address Translation (NAT) Screens 147
9.2 Using NAT
Note: You must create a firewall rule in addition to setting up
SUA/NAT, to allow traffic from the WAN to be forwarded
through the Prestige.
9.2.1 SUA (Single User Account) Versus NAT
SUA (Single User Account) is a ZyNOS implementation of a subset of NAT that supports two
types of mapping, Many-to-One and Server. The Prestige also supports Full Feature NAT to
map multiple global IP addresses to multiple private LAN IP addresses of clients or servers
using mapping types. Select either SUA Only or Full Feature in the WAN IP screen.
9.3 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.
9.3.1 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
Note: If you do not assign a Default Server IP Address, the
Prestige discards all packets received for ports that are not
specified in this screen or remote management.