[c-nsp] DOS attack

[sherif mostafa]

Dears,
 
Could anyone help please as I've faced an error message "DOS"  below that caused high CPU usage:
 
 
ERROR 08/02/2010 16:22:46 CAI dosProtection: Flow is suspicious:
GigabitEthernet11/0.410 for control protocol: IP TTL Expired source MAC
0018.742f.b380 with rate 241 pps
ERROR 08/02/2010 16:24:11 CAI dosProtection: Flow is suspicious:
GigabitEthernet11/0.410 for control protocol: IP TTL Expired source MAC
0018.742f.b380 with rate 11 pps
ERROR 08/02/2010 16:24:38 CAI dosProtection: Flow is suspicious:
GigabitEthernet11/0.410 for control protocol: IP TTL Expired source MAC
0018.742f.b380 with rate 10 pps
ERROR 08/02/2010 16:24:59 CAI dosProtection: Flow is suspicious:
GigabitEthernet11/0.410 for control protocol: IP TTL Expired source MAC
0018.742f.b380 with rate 10 pps
ERROR 08/02/2010 16:26:57 CAI dosProtection: Flow is suspicious:
GigabitEthernet11/0.410 for control protocol: IP TTL Expired source MAC
0018.742f.b380 with rate 20 pps