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Chapter 2 -Getting to Know the Internet Security Router
ASUS SL1200
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Use of the wild card for composing filter rules
• Filter Rule priorities
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Time based filters
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Application specific filters
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User group based filters for remote access
2.4.1.2 Stateful Packet Inspection
The ASUS SL1200's firewall uses “stateful packet inspection” that extracts
state-related information required for the security decision from the packet
and maintains this information for evaluating subsequent connection
attempts. It has awareness of application and creates dynamic sessions
that allow dynamic connections so that no ports need to be opened other
than the required ones. This provides a solution which is highly secure and
that offers scalability and extensibility.
2.4.1.3 Defense against DoS Attacks
The firewall has an Attack Defense Engine that protects internal networks
from known types of Internet attacks. It provides automatic protection from
Denial of Service (DoS) attacks such as SYN flooding, IP smurfing, LAND,
Ping of Death and all re-assembly attacks. It can drop ICMP redirects and
IP loose/strict source routing packets. For example, the router's firewall
provides protection from “WinNuke”, a widely used program that remotely
crash unprotected Windows systems in the Internet. The Internet Security
Router Firewall also provides protection from a variety of common Internet
attacks such as IP Spoofing, Ping of Death, Land Attack, Reassembly and
SYN flooding.
Table 2.3 lists the type of attack protections provided by the router.
