Draytek Vigor 3100 Series User Manual page 49

Subnet Mask
Operator, Start Port
and End Port
Keep State
Fragments
E E x x a a m m p p
As stated before, all the traffic will be separated and arbitrated using on of two IP filters: call
filter or data filter. You may preset 12 call filters and data filters in Filter Setup and even link
them in a serial manner. Each filter set is composed by 7 filter rules, which can be further
defined. After that, in General Setup you may specify one set for call filter and one set for
data filter to execute first.
Vigor3100 Series User's Guide
Select the Subnet Mask for the IP Address column for this filter rule
to apply from the drop-down menu.
The operator column specifies the port number settings. If the Start
Port is empty, the Start Port and the End Port column will be
ignored. The filter rule will filter out any port number.
(=)
number to be the value of the Start Port. Otherwise, the port
number ranges between the Start Port and the End Port (including
the Start Port and the End Port).
(!=)If the End Port is empty, the port number is not equal to the
value of the Start Port. Otherwise, this port number is not between
the Start Port and the End Port (including the Start Port and End
Port).
(>) Specify the port number is larger than the Start Port (includes
the Start Port).
(<) Specify the port number is less than the Start Port (includes the
Start Port).
This function should work along with Direction, Protocol, IP address,
Subnet Mask, Operator, Start Port and End Port settings. It is used
for Data Filter only.
Keep State is in the same nature of modern term Stateful Packet
Inspection. It tracks packets, and accept the packets with appropriate
characteristics showing its state is legal as the protocol defines. It
will deny unsolicited incoming data. You may select protocols from
any, TCP, UDP, TCP/UDP, ICMP and IGMP.
Specify the action for fragmented packets. And it is used for Data
Filter only.
Don't care -No action will be taken towards fragmented packets.
Unfragmented -Apply the rule to unfragmented packets.
Fragmented - Apply the rule to fragmented packets.
Too Short - Apply the rule only to packets that are too short to contain
a complete header.
l l e e
If the End Port is empty, the filter rule will set the port
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