Atlantis Land A02-WRA4-54G ユーザーズマニュアル

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                                                                                              I-FLY WIRELESS ROUTER ADSL 
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3.6.3.4   Firewall
 
Your router includes a full SPI (Stateful Packet Inspection) firewall for controlling Internet access 
from your LAN, as well as helping to prevent attacks from hackers. In addition to this, when using 
NAT (Network Address Translation. Please see the WAN  configuration section for more details on 
NAT) the router acts as a “natural” Internet firewall, as all PCs on your LAN will use private IP 
addresses that cannot be directly accessed from the Internet.
 
Firewall: Prevents access from outside your network. The router provides three levels of security 
support: 
NAT natural firewall: This masks LAN users’ IP addresses which are invisible to outside users on 
the Internet, making it much more difficult for a hacker to target a machine on your network. 
This natural firewall is on when NAT function is enabled. 
Firewall Security and Policy (General Settings): Inbound direction of Packet Filter rules to prevent 
unauthorized computers or applications accessing your local network from the Internet. 
Intrusion Detection: Enable Intrusion Detection to detect, prevent and log malicious attacks. 
Access Control: Prevents access from PCs on your local network: 
Firewall Security and Policy (General Settings): Outbound direction of Packet Filter rules to 
prevent unauthorized computers or applications accessing the Internet. 
MAC Filter rules: To prevent unauthorized computers accessing the Internet. 
URL Filter: To block PCs on your local network from unwanted websites. 
 
You can find six items under the Firewall section: General Settings, Packet Filter, Intrusion Detection, 
MAC Address Filter, URL Filter and Firewall Log.
 
 
You can choose not to enable Firewall, to add all filter rules by yourself, or enable the Firewall using 
preset filter rules and modify the port filter rules as required. The Packet Filter is divided into two 
sections: Port Filters and Address Filters, used to filter packets based-on Applications (Port) or IP 
addresses. 
There are four options when you enable the Firewall, they are: 
•  All blocked/User-defined: no pre-defined port or address filter rules by default, meaning that 
all inbound (Internet to LAN) and outbound (LAN to Internet) packets will be blocked. Users 
have to add their own filter rules for further access to the Internet. 
•  High/Medium/Low security level: the pre-defined port filter rules for High, Medium and Low 
security are displayed in Port Filters of Packet Filter. 
Select either High, Medium or  Low security level to enable the Firewall. The only difference 
between these three security levels is the preset port filter rules in the Packet Filter. Firewall 
functionality is the same for all levels; it is only the list of preset port filter that changes between each 
setting. 
If you choose of the preset security levels and then add custom filters, you may temporarily disable the 
firewall and recover your custom filter settings by re-selecting the same security level. 
The “Block WAN Request” is a stand-alone function and not relate to whether security enable or 
disable. Mostly it is for preventing any scan tools from WAN site by hacker.