ZyXEL Communications P-202 - Manual (Page 80)

P-202H Plus v2 Support Notes
protocol filters=
device filters=
A filter for blocking the NetBIOS packets
• Introduction
The NETBIOS packets contain port numbers and need to be blocked in this case.
They are port number 137, 138 and 139 with UDP or TCP protocol. In addition,
the NETBIOS packet used to look for a remote DNS server can also trigger the
call. Therefore, the filter rules should cover the above packets.
• Configuration
The packets which need to be blocked are as following. Please configure two
filter sets with 4 and 2 rules respectively based on the following packets in SMT
menu 21.
Filter Set 1:
o Rule 1-Destination port number 137 with protocol number 6 (TCP)
o
Rule 2-Destination port number 137 with protocol number 17 (UDP)
o Rule 3-Destination port number 138 with protocol number 6 (TCP)
o
Rule 4-Destination port number 138 with protocol number 17 (UDP)
o Rule 5-Destination port number 139 with protocol number 6 (TCP)
o
Rule 6-Destination port number 139 with protocol number 17 (UDP)
Filter Set 2:
o
Rule 1-Source port number 137, Destination port number 53 with
protocol number 6 (TCP)
o
Rule 2-Source port number 137, Destination port number 53 with
protocol number 17 (UDP)
Before starting to set the filter rules, please enter a name for each filter set in the
'Comments' field first.
Menu 21 - Filter Set Configuration
Filter Filter
Set # Comments Set # Comments
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