ZyXEL Communications NBG-415N, User Manual

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ZyXEL NBG-415N User’s Guide
Chapter 7 Advanced 74
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.
7.2.1 Common Services and Port Numbers
The most often used port numbers are shown in the following table. Please refer to RFC 1700
for further information about port numbers.
7.2.2 Virtual Server Setup
To configure virtual server settings, click Advanced > Virtual Server .
Table 27 Virtual Server: Common Services and Port Numbers
SERVICES PORT NUMBER
ECHO 7
FTP (File Transfer Protocol) 21
SMTP (Simple Mail Transfer Protocol) 25
DNS (Domain Name System) 53
Finger 79
HTTP (Hyper Text Transfer protocol or WWW, Web) 80
POP3 (Post Office Protocol) 110
NNTP (Network News Transport Protocol) 119
SNMP (Simple Network Management Protocol) 161
SNMP trap 162
PPTP (Point-to-Point Tunneling Protocol) 1723