Wireless Gateway Series User's Guide

ZyAIR Wireless Gateway Series User’s Guide
11-6 Introduction to Firewalls
Figure 11-4 Smurf Attack
 ICMP Vulnerability
ICMP is an error-reporting protocol that works in concert with IP. The following ICMP types trigger an alert:
Table 11-2 ICMP Commands That Trigger Alerts
5 REDIRECT
13 TIMESTAMP_REQUEST
14 TIMESTAMP_REPLY
17 ADDRESS_MASK_REQUEST
18 ADDRESS_MASK_REPLY
 Illegal Commands (NetBIOS and SMTP)
The only legal NetBIOS commands are the following - all others are illegal.
Table 11-3 Legal NetBIOS Commands
MESSAGE:
REQUEST:
POSITIVE:
NEGATIVE:
RETARGET:
KEEPALIVE:
All SMTP commands are illegal except for those displayed in the following tables.