NETGEAR CBVG834G, Руководство пользователя для администраторов

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Wireless Cable Voice Gateway Model CBVG834G Adminstrators User Manual
3-10 Protecting Your Network
v1.0, February 2008
3. For the time of day, either select the All Day check box or specify a Start Time and End Time
from the pull-down menus.
4. Click Add . The new Port Blocking rule is in the Outbound Rules table.
To delete an existing rule:
1. Select the rule from the Port Filter List .
2. Click Delete .
Port Forwarding
You can use port forwarding to set up a rule that directs inbound traffic for a particular service to a
local server (for example, a Web server or game server) based on the destination port. This makes
the server visible and available to the Internet.
Unless you set up port forwarding, the gateway prevents this type of traffic.The gateway uses
Network Address Translation (NAT). NAT presents a single IP address for your network to the
Internet. Outside users cannot directly address your local computers.
Before setting up Port Forwarding, consider the following:
• If the IP address of the local server PC is assigned by DHCP, it may change when the PC is
rebooted. To avoid this, you can assign a static IP address to your server outside the range that
is assigned by DHCP, but in the same subnet as the rest of your LAN. By default, the IP
addresses in the range of 192.168.0.2 through 192.168.0.9 are reserved for this.
• Local computers must access the local server using the local LAN address of the computer
(192.168.0.XXX, by default). Attempts by local computers to access the server using the
external WAN IP address will fail.
Remember that allowing inbound services opens holes in your firewall. Only enable those ports
that are necessary for your network.
Note: Some residential broadband ISP accounts do not allow you to run any server
processes (such as a Web or FTP server) from your location. Your ISP may check
for servers and may suspend your account if it discovers active services at your
location. If you are unsure, refer to the acceptable use policy of your ISP.