Port Forwarding: Services And Port Numbers; Table 9-3 Services And Port Numbers - ZyXEL Communications ZyAIR User Manual

ZyAIR Wireless Gateway Series User's Guide
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 a Default Server IP Address, then all packets received for ports

9.2.1 Port Forwarding: Services and 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 server 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.
The most often used port numbers are shown in the following table. Please refer to RFC 1700 for further
information about port numbers. Please also refer to the Supporting CD for more examples and details on
SUA/NAT.
ECHO
FTP (File Transfer Protocol)
SMTP (Simple Mail Transfer Protocol)
DNS (Domain Name System)
Finger
HTTP (Hyper Text Transfer protocol or WWW, Web)
9-6
not specified in this screen will be discarded.

Table 9-3 Services and Port Numbers

SERVICES PORT NUMBER
7
21
25
53
79
80
SUA/NAT