4.3.2 Routing

If you have another router with a LAN-to-LAN connection, you may create a static routing on

the router that is the gateway to Internet.

#:

Item number

Dest IP:

IP address of the destination network

Mask:

The destination mask address.

Gateway IP:

IP address of the gateway or existing interface that this route uses.

Metric:

It represents the cost of transmission for routing purposes. The number need not

be precise, but it must be between 1 and 15.

Device:

Media/channel selected to append the route.

Use:

Counter for access times.

Edit:

Edit the route; this icon is not shown for system default route.

Drop:

Drop the route; this icon is not shown for system default route.

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ADD Route

Destination IP Address

：

This is the destination subnet IP address.

IP Subnet Mask

：

It is the destination IP addresses based on above destination subnet IP

Gateway IP Address

：

This is the gateway IP address to which packets are to be

forwarded.

Metric

：

It represents the cost of transmission for routing purposes. The number need not

be precise, but it must be between 1 and 15.

Announced in RIP:

This parameter determines if the Prestige will include the route to the

remote node in its RIP broadcasts. Set “Yes”, it is kept private and is not included in RIP

broadcasts. Set “No”, the remote node will be propagated to other hosts through RIP

broadcasts.

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4.3.3 NAT

The

NAT (Network Address Translation - NAT, RFC 1631) is the translation of the IP address

of a host in a packet. The default setting is

Dynamic NAPT

. It provides dynamic Network

Address Translation capability between LAN and multiple WAN connections, and the LAN

traffic is routed to appropriate WAN connections based on the destination IP addresses and

Route Table. This eliminates the need for the static NAT session configuration between

multiple LAN clients and multiple WAN connections.

Virtual Circuit:

VPI (Virtual Path Identifier) and VCI (Virtual Channel Identifier) define a

virtual circuit. There are eight groups of PVC can be defined and used.

Number of IPs:

User can select Single or Multiple.

DMZ

The DMZ Host is a local computer exposed to the Internet. When setting a particular internal

IP address as the DMZ Host, all incoming packets will be checked by the Firewall and NAT

algorithms then passed to the DMZ host, when a packet received does not use a port

number used by any other Virtual Server entries.

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DMZ:

~

Disabled:

As set in default setting, it disables the DMZ function.

~

Enabled:

It activates your DMZ function.

DMZ Host Address:

Give a static IP address to the DMZ Host when

Enabled

radio

button is checked. Be aware that this IP will be exposed to the WAN/Internet.

Select the

Apply

button to apply your changes.

Virtual Server

In TCP/IP and UDP networks a port is a 16-bit number used to identify which application

program (usually a server) incoming connections should be delivered to. Some ports have

numbers that are pre-assigned to them by the IANA (the Internet Assigned Numbers

Authority), and these are referred to as “well-known ports”. Servers follow the well-known

port assignments so clients can locate them.

If you wish to run a server on your network that can be accessed from the WAN (i.e. from

other machines on the Internet that are outside your local network), or any application that

can accept incoming connections (e.g. Peer-to-peer/P2P software such as instant

messaging applications and P2P file-sharing applications) and are using NAT (Network

Address Translation), then you will usually need to configure your router to forward these

incoming connection attempts using specific ports to the PC on your network running the

application. You will also need to use port forwarding if you want to host an online game

server.

The reason for this is that when using NAT, your publicly accessible IP address will be used

by and point to your router, which then needs to deliver all traffic to the private IP addresses

used by your PCs. Please see the

WAN

configuration section of this manual for more

information on NAT.

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The device can be configured as a virtual server so that remote users accessing services

such as Web or FTP services via the public (WAN) IP address can be automatically

redirected to local servers in the LAN network. Depending on the requested service

(TCP/UDP port number), the device redirects the external service request to the appropriate

server within the LAN network.

Rule Index:

Choose the rule number.

Start Port Number:

Enter a port number in this field.

End Port Number:

Enter a port number in this field.

Local

IP Address:

Enter your server IP address in this field.

IP Address Mapping

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