Draytek Vigor2500V Manual page 68

Firewall
Fragments: Specifies a fragmented packets action.
(Do not Care): Specifies no fragment options in the filter rule.
Unfragmented: Applies the rule to unfragmented packets.
Fragmented: Applies the rule to fragmented packets.
Too Short: Applies the rule only to packets which are too short to
contain a complete header.
6.6 An Example of Restricting Unauthorized Internet
Services
This section will show a simple example to restrict someone from
accessing WWW services. In this example, we assume the IP
address of the access-restricted user is 192.168.1.10. The filter
rule is created in the Data Filter set where Port 80 is the HTTP
protocol port number for WWW services and is shown as below.
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