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Remove

You can remove any item listed in

IP Bind List

. Simply click

and select the one, and click

Remove

. The selected item will be

removed from the

IP Bind List

.

Note:

Before you select

Strict Bind

, you have to bind one set of IP/MAC address for one

PC. If not, no one of the PCs can access into Internet. And the web configurator of the router

might not be accessed.

3.3 NAT

Usually, the router serves as an NAT (Network Address Translation) router. NAT is a

mechanism that one or more private IP addresses can be mapped into a single public one.

Public IP address is usually assigned by your ISP, for which you may get charged. Private IP

addresses are recognized only among internal hosts.

When the outgoing packets destined to some public server on the Internet reach the NAT

router, the router will change its source address into the public IP address of the router, select

the available public port, and then forward it. At the same time, the router shall list an entry in

a table to memorize this address/port-mapping relationship. When the public server response,

the incoming traffic, of course, is destined to the router’s public IP address and the router will

do the inversion based on its table. Therefore, the internal host can communicate with external

host smoothly.

The benefit of the NAT includes:

z

Save cost on applying public IP address and apply efficient usage of IP address.

NAT allows the internal IP addresses of local hosts to be translated into one public IP

address, thus you can have only one IP address on behalf of the entire internal hosts.

z

Enhance security of the internal network by obscuring the IP address.

There are

many attacks aiming victims based on the IP address. Since the attacker cannot be aware

of any private IP addresses, the NAT function can protect the internal network.

On NAT page, you will see the private IP address defined in RFC-1918. Usually we use the

192.168.1.0/24 subnet for the router. As stated before, the NAT facility can map one or

more IP addresses and/or service ports into different specified services. In other words, the

NAT function can be achieved by using port mapping methods.

Below shows the menu items for NAT.

3.3.1 Hardware NAT

Hardware-base Acceleration Engine, also named Protocol Processing Engine API is the

function that Draytek provides to extremely speed up the NAT performance.

While the hardware acceleration mechanism is activated, most of the bandwidth usage will

be concentrated on the specific sessions which increase transmission speed to get ultimately

accelerated.

With Hardware NAT, LAN to WAN NAT throughput can be over 900M bps. But be sure that

your PC has Giga Ethernet and connect with CAT6 Ethernet cable.

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3.3.2 Open Ports

Open Ports

allows you to open a range of

ports for the traffic of special applications.

Common application of Open Ports includes P2P application (e.g., BT, KaZaA, Gnutella,

WinMX, eMule and others), Internet Camera etc. Ensure that you keep the application

involved up-to-date to avoid falling victim to any security exploits.

To add a new open port, click

Add new entry

.

Name

Specify the name for the defined network service.

Protocol

Specify the transport layer protocol. It could be

TCP

,

UDP

and

TCP+UDP

.

Start Port

Specify the starting port number of the service offered by the

local host.

End Port (optional)

Specify the ending port number of the service offered by the

local host.

Local Host

Enter the private IP address of the local host.

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Local Port (optional)

If it is configured, the forwarded traffic is mapped to this port

on the local host.

3.3.3 DMZ Host

Vigor router provides a facility

DMZ Host

that maps ALL unsolicited data on any protocol to

a single host in the LAN. Regular web surfing and other such Internet activities from other

clients will continue to work without inappropriate interruption.

DMZ Host

allows a defined

internal user to be totally exposed to the Internet, which usually helps some special

applications such as Netmeeting or Internet Games etc.

Note:

The security properties of NAT are somewhat bypassed if you set up DMZ host. We

suggest you to add additional filter rules or a secondary firewall.

Click

DMZ Host

to open the following page:

Enable

Check to enable the DMZ Host function.

DMZ IP

Enter the private IP address of the DMZ host, or click

Choose

PC

to select one.

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3.4 Bandwidth Management

Below shows the menu items for Bandwidth Management.

3.4.1 Session Limit

A PC with private IP address can access to the Internet via NAT router. The router will

generate the records of NAT sessions for such connection. The P2P (Peer to Peer) applications

(e.g., BitTorrent) always need many sessions for procession and also they will occupy over

resources which might result in important accesses impacted. To solve the problem, you can

use limit session to limit the session procession for specified Hosts.

In the

Bandwidth Management

menu, click

Sessions Limit

to open the web page.

To activate the function of limit session, simply click

Enable

and set the default session limit.

Disable

Click this button to close the function of limit session.

Enable

Click this button to activate the function of limit session.

Default Session Limit

Defines the default session number used for each computer in

LAN.

Limitation List

Displays a list of specific limitations that you set on this web

page.

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Start IP

Defines the start LAN IP address for limit session.

End IP

Defines the end LAN IP address for limit session.

Sessions Limit

Defines the available session number for each host in the

specific range of IP addresses. If you do not set the session

number in this field, the system will use the default session limit

for the specific limitation you set for each index.

Add

Adds the specific session limitation onto the list above.

Edit

Allows you to edit the settings for the selected limitation.

Delete

Remove the selected settings existing on the limitation list.

When you finish adding a new session limit, simply click

OK

.

3.4.2 Bandwidth Limit

The downstream or upstream from FTP, HTTP or some P2P applications will occupy large of

bandwidth and affect the applications for other programs. Please use Limit Bandwidth to make

the bandwidth usage more efficient.

In the

Bandwidth Management

menu, click

Bandwidth Limit

to open the web page.

To activate the function of limit bandwidth, simply click

Enable

and set the default or

user-defined upstream and downstream limit.

Disable

Click this button to close the function of limit bandwidth.

Enable

Click this button to activate the function of limit bandwidth.