Vigor2800 Series User’s Guide
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IP spoofing. A Land attack occurs when an attacker sends spoofed
SYN packets with the identical source and destination addresses, as
well as the port number to victims.
Block Unknown
Protocol
Check the box to activate the Block Unknown Protocol function.
Individual IP packet has a protocol field in the datagram header to
indicate the protocol type running over the upper layer. However,
the protocol types greater than 100 are reserved and undefined at
this time. Therefore, the router should have ability to detect and
reject this kind of packets.
Warning Messages
We provide Syslog function for user to retrieve message from Vigor
router. The user, as a Syslog Server, shall receive the report sending
from Vigor router which is a Syslog Client.
All the warning messages related to
DoS defense
will be sent to user
and user can review it through Syslog daemon. Look for the
keyword
DoS
in the message, followed by a name to indicate what
kind of attacks is detected.
3.4.7 URL Content Filter
Based on the list of user defined keywords, the
URL Content Filter
facility in Vigor router
inspects the URL string in every outgoing HTTP request. No matter the URL string is found
full or partial matched with a keyword, the Vigor router will block the associated HTTP
connection.
For example, if you add key words such as “sex”, Vigor router will limit web access to web
sites or web pages such as “www.sex.com”, ”www.backdoor.net/images/sex/p_386.html”.
Or you may simply specify the full or partial URL such as “www.sex.com” or “sex.com”.
Also the Vigor router will discard any request that tries to retrieve the malicious code.
Click
Firewall
and click
URL Content Filter
to open the setup page.