ZyXEL Communications NVG2053, Руководство пользователя

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Chapter 12 Network Address Translation (NAT)
NVG2053 User’s Guide
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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.
Note: 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.
Port forwarding allows you to define the local servers to which the incoming
services will be forwarded. To change your NVG2053’s port forwarding settings,
click Network > NAT > Port Forwarding. The screen appears as shown.
Note: If you do not assign a Default Server , the NVG2053 discards all packets
received for ports that are not specified in this screen or remote management.
Refer to Appendix F on page 319 for port numbers commonly used for particular
services.
Figure 61 Network > NAT > Port Forwarding
The following table describes the labels in this screen.
Table 45 Network > NAT > Port Forwarding
LABEL DESCRIPTION
Default Server Setup
Default Server
In addition to the servers for specified services, NAT supports a default
server. A default server receives packets from ports that are not
specified in the Port Forwarding screen.
If you do not assign a Default Server IP address, the NVG2053
discards all packets received for ports that are not specified in the Port
Forwarding screen or remote management.