monitoring number of simultaneos connection

[Roberto Tagliaferri]

Is there a way to monitor the number of simultaneous open port from the 
same ip?
I need to alert when an (stupid...) attacker send a thing like this

tcp        0      0 151.8.36.12:80          206.225.82.32:9654      
SYN_RECV   
tcp        0      0 151.8.36.12:80          206.225.82.32:63256     
SYN_RECV   
tcp        0      0 151.8.36.12:80          206.225.82.32:11611     
SYN_RECV   
tcp        0      0 151.8.36.12:80          206.225.82.32:55544     
SYN_RECV   
tcp        0      0 151.8.36.12:80          206.225.82.32:55045     
SYN_RECV   
tcp        0      0 151.8.36.12:80          206.225.82.32:949       
SYN_RECV   
tcp        0      0 151.8.36.12:80          206.225.82.32:19880     
SYN_RECV   
tcp        0      0 151.8.36.12:80          206.225.82.32:13331     
SYN_RECV   
tcp        0      0 151.8.36.12:80          206.225.82.32:31280     
SYN_RECV   
tcp        0      0 151.8.36.12:80          206.225.82.32:44500     
SYN_RECV   
tcp        0      0 151.8.36.12:80          206.225.82.32:11909     
SYN_RECV   
tcp        0      0 151.8.36.12:80          206.225.82.32:58313     
SYN_RECV   
tcp        0      0 151.8.36.12:80          206.225.82.32:47932     
SYN_RECV   
tcp        0      0 151.8.36.12:80          206.225.82.32:15468     
SYN_RECV   
tcp        0      0 151.8.36.12:80          206.225.82.32:2060      
SYN_RECV   
tcp        0      0 151.8.36.12:80          206.225.82.32:56875     
SYN_RECV   
tcp        0      0 151.8.36.12:80          206.225.82.32:45630     
SYN_RECV   


-- 
Roberto Tagliaferri
Responsabile Progettazione & Produzione
TosNet s.r.l. - Internet Service Provider
r.tagliaferri at tosnet.it
www.tosnet.it