ZyXEL Communications Parental Control Gateway HS100/HS100W - Manual (Page 265)

HomeSafe User’s Guide
27-2 Filter Configuration
apply up to four filter sets to a particular port to block multiple types of packets. With each filter
set having up to six rules, you can have a maximum of 24 rules active for a single port.
Sets of factory default filter rules have been configured in menu 21 to prevent NetBIOS traffic
from triggering calls and to prevent incoming telnet sessions. A summary of their filter rules is
shown in the figures that follow.
The following figure illustrates the logic flow when executing a filter rule. See also Figure 27-7
for the logic flow when executing an IP filter.
Start
Fetch First
Filter Set
Fetch First
Filter Rule
Active?
Execute
Filter Rule
Fetch Next
Filter Rule
Next filter
Rule
Available?
Fetch Next
Filter Set
Next Filter Set
Available?
Accept Packet Drop Packet
Yes
No
Yes
No
Yes
Packet into
filter
Filter Set
Forward
Drop
No
Check
Next
Rule
Figure 27-2 Filter Rule Process
You can apply up to four filter sets to a particular port to block multiple types of packets. With
each filter set having up to six rules, you can have a maximum of 24 rules active for a single port.