Draytek Vigor IPPBX 2820n, Руководство пользователя

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VigorIPPBX 2820 Series User’s Guide 226
Internet.
Disable Click this radio button to disable this function. All the settings
on this page will be invalid.
Strict Bind Click this radio button to block the connection of the IP/MAC
which is not listed in IP Bind List.
ARP Table This table is the LAN ARP table of this router. The information
for IP and MAC will be displayed in this field. Each pair of IP
and MAC address listed in ARP table can be selected and added
to IP Bind List by clicking
Add below .
Add and Edit IP Address
–
Type the IP address that will be used for the
specified MAC address.
Mac Address
–
Type the MAC address that is used to bind
with the assigned IP address.
Refresh It is used to refresh the ARP table. When there is one new PC
added to the LAN, you can click this link to obtain the newly
ARP table information.
IP Bind List It displays a list for the IP bind to MAC information.
Add It allows you to add the one you choose from the ARP table or
the IP/MAC address typed in
Add and Edit to the table of IP
Bind List .
Edit It allows you to edit and modify the selected IP address and
MAC address that you create before.
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.
5
5
.
.
3
3
N
N
A
A
T
T
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:

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.