ZyXEL Communications ZyWALL 2 Plus - Manual (Page 340)

Chapter 17 Network Address Translation (NAT)
ZyWALL 2 Plus User’s Guide
340
The following table describes the labels in this screen.
17.5 Port Forwarding
A port forwarding 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 NAT 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.
17.5.1 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.
Table 97 ADVANCED > NAT > Address Mapping > Edit
LABEL DESCRIPTION
Type Choose the port mapping type from one of the following.
1. One-to-One: One-to-One mode maps one local IP address to one global IP
address. Note that port numbers do not change for One-to-One NAT mapping
type.
2. Many-to-One: Many-to-One mode maps multiple local IP addresses to one
global IP address. This is equivalent to SUA (i.e., PAT, port address translation),
ZyXEL's Single User Account feature.
3. Many-to-Many Overload: Many-to-Many Overload mode maps multiple local
IP addresses to shared global IP addresses.
4. Many One-to-One: Many One-to-One mode maps each local IP address to
unique global IP addresses.
5. Server: This type allows you to specify inside servers of different services
behind the NAT to be accessible to the outside world.
Local Start IP This is the starting Inside Local IP Address (ILA). Local IP addresses are N/A for
Server port mapping.
Local End IP This is the end Inside Local IP Address (ILA). If your rule is for all local IP
addresses, then enter 0.0.0.0 as the Local Start IP address and 255.255.255.255
as the Local End IP address.
This field is N/A for One-to-One and Server mapping types.
Global Start IP This is the starting Inside Global IP Address (IGA). Enter 0.0.0.0 here if you have
a dynamic IP address from your ISP.
Global End IP This is the ending Inside Global IP Address (IGA). This field is N/A for One-to-
One, Many-to-One and Server mapping types.
Apply Click Apply to save your changes back to the ZyWALL.
Cancel Click Cancel to exit this screen without saving.