ZyXEL Router Prestige 334 User Manual

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The following table summarizes these types.
7.2  Using NAT
7.2.1  SUA (Single User Account) Versus NAT
SUA (Single User Account) is a ZyNOS implementation of a subset of NAT that supports two 
types of mapping, Many-to-One and Server. The Prestige also supports Full Feature NAT to 
map multiple global IP addresses to multiple private LAN IP addresses of clients or servers 
using mapping types. Select either SUA Only or Full...

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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...

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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.
7.3.3  Configuring Servers Behind SUA (Example)
Lets 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...

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Figure 29   Multiple Servers Behind NAT Example
7.4  Configuring SUA Server 
Click SUA/NAT to open the SUA Server screen. 
Refer to Table 23 for port numbers commonly used for particular services. 
Note: If you do not assign a Default Server IP Address, the 
Prestige discards all packets received for ports that are not 
specified in this screen or remote management. 

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Figure 30   SUA/NAT Setup
The following table describes the labels in this screen.
Table 24   SUA/NAT Setup
LABELDESCRIPTION
Default ServerIn addition to the servers for specified services, NAT supports a default server. A 
default server receives packets from ports that are not specified in this screen. 
If you do not assign a Default Server IP Address, the Prestige discards all packets 
received for ports that are not...

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7.5  Configuring Address Mapping
Ordering your rules is important because the Prestige applies the rules in the order that you 
specify. When a rule matches the current packet, the Prestige takes the corresponding action 
and the remaining rules are ignored. If there are any empty rules before your new configured 
rule, your configured rule will be pushed up by that number of empty rules. For example, if 
you have already...

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7.5.1  Configuring Address Mapping 
To edit an address mapping rule, select the radio button of a rule and click the Edit button to 
display the screen shown next.  
Ty p e1. One-to-One mode maps one local IP address to one global IP address. Note that 
port numbers do not change for the One-to-one NAT mapping type.
2. Many-to-One mode maps multiple local IP addresses to one global IP address. 
This is equivalent to SUA...

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Figure 32   Address Mapping Edit
The following table describes the labels in this screen.
Table 26   Address Mapping Edit
LABELDESCRIPTION
Ty peChoose the port mapping type from one of the following. 
1. One-to-One: One-to-one mode maps one local IP address to one global IP 
address. Note that port numbers do not change for One-to-one NAT mapping 
type.
2. Many-to-One: Many-to-One mode maps multiple local IP addresses to one...

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7.6  Trigger Port Forwarding
Some services use a dedicated range of ports on the client side and a dedicated range of ports 
on the server side. With regular port forwarding you set a forwarding port in NAT to forward a 
service (coming in from the server on the WAN) to the IP address of a computer on the client 
side (LAN). The problem is that port forwarding only forwards a service to a single LAN IP 
address. In order to...

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7.6.2  Two Points To Remember About Trigger Ports
1Trigger events only happen on data that is going coming from inside the Prestige and 
going to the outside.
2If an application needs a continuous data stream, that port (range) will be tied up so that 
another computer on the LAN can’t trigger it. 
7.7  Configuring Trigger Port Forwarding
To change your Prestige’s trigger port settings, click SUA/NAT and the Trigger Port...