ZyXEL Communications P-660HW-D Series 사용자 설명서
P-660HW-D Series User’s Guide
147
Chapter 9 Firewalls
Figure 83 Smurf Attack
9.4.2.1 ICMP Vulnerability
ICMP is an error-reporting protocol that works in concert with IP. The following ICMP types
trigger an alert:
trigger an alert:
9.4.2.2 Illegal Commands (NetBIOS and SMTP)
The only legal NetBIOS commands are the following - all others are illegal.
All SMTP commands are illegal except for those displayed in the following tables.
Table 53 ICMP Commands That Trigger Alerts
5
REDIRECT
13
TIMESTAMP_REQUEST
14
TIMESTAMP_REPLY
17
ADDRESS_MASK_REQUEST
18
ADDRESS_MASK_REPLY
Table 54 Legal NetBIOS Commands
MESSAGE:
REQUEST:
POSITIVE:
VE:
RETARGET:
KEEPALIVE:
Table 55 Legal SMTP Commands
AUTH
DATA
EHLO
ETRN
EXPN
HELO
HELP
MAIL
NOOP
QUIT
RCPT
RSET
SAML
SEND
SOML
TURN
VRFY