19216811.liveVigor2130 Series User’s Guide
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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.