ZyXEL Communications ZyXEL ZyWALL P1, Руководство пользователя

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ZyWALL P1 User’s Guide
Chapter 11 Network Address Translation (NAT) 181
11.4 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.
11.4.1 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 ZyWALL discards all
packets received for ports that are not specified here or in the remote
management setup.
11.4.2 Port Forwarding: Services and Port Numbers
The ZyWALL provides the additional safety for connecting your publicly accessible servers.
Use the Port Forwarding screen to forward incoming service requests to the server(s) on your
local network.
Apply Click Apply to save your changes back to the ZyWALL.
Reset Click Reset to begin configuring this screen afresh.
Table 64 NAT Overview (continued)
LABEL DESCRIPTION