Draytek Vigor 2910 User Manual page 82

Block Unknown
Protocol
Warning Messages
76
SYN packets with the identical source and destination addresses,
as well as the port number to victims.
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.
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.
Vigor2910 Series User's Guide