ZyXEL p-330w Guia Do Utilizador

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ZyXEL P-330W User’s Guide
Chapter 6 Advanced Options
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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.
The most often used port numbers are shown in the following table. Please refer to RFC 1700 
for further information about port numbers. .
6.5.0.1  Configuring Servers Behind SUA (Example)
Let's say you want to assign ports 21-25 to one FTP, Telnet and SMTP server (A in the 
example), port 80 to another (B in the example) and assign a default server IP address of 
192.168.10.35 to a third (C in the example). You assign the LAN IP addresses and the ISP 
assigns the WAN IP address. The NAT network appears as a single host on the Internet
Table 30   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