Draytek Vigor2830 Series User Manual page 170

Block ICMP Fragment
Block Unknown Protocol Check the box to activate the Block Unknown Protocol
Warning Messages
Vigor2830 Series User's Guide
once they re-construct the packets. The Vigor routers will
block any packets realizing this attacking activity.
Check the box to activate the Block ICMP fragment function.
Any ICMP packets with more fragment bit set are dropped.
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.
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.
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