F3726, F3211, F3174, R5135, R3816-HP Firewalls and UTM Devices Access Control Configuration Guide-6PW100

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A wildcard mask, also called an inverse mask, is a 32-bit binary and represented in dotted decimal
notation. In contrast to a network mask, the 0 bits in a wildcard mask represent "do care" bits, and the
1 bits represent "don't care" bits. If the "do care" bits in an IP address are identical to the "do care" bits
in an IP address criterion, the IP address matches the criterion. All "don't care" bits are ignored. The 0s
and 1s in a wildcard mask can be noncontiguous. For example, 0.255.0.255 is a valid wildcard mask.
101BRule comments and rule range remarks
Add a comment about an ACL rule to make it easy to understand. The rule comment appears below the
rule statement.
In addition, add a rule range remark to indicate the start or end of a range of rules created for the same
purpose.
102BRule numbering
ACL rules can be manually numbered or automatically numbered. This section describes how automatic
ACL rule numbering works.
261BRule numbering step
If you do not assign an ID to the rule you are creating, the system automatically assigns it a rule ID. The
rule numbering step sets the increment by which the system automatically numbers rules. For example, the
default ACL rule numbering step is 5. If you do not assign IDs to rules you are creating, they are
automatically numbered 0, 5, 10, 15, and so on. The wider the numbering step, the more rules you can
insert between two rules.
By introducing a gap between rules rather than contiguously numbering rules, you have the flexibility of
inserting rules in an ACL. This feature is important for a config order ACL, where ACL rules are matched
in ascending order of rule ID.
262BAutomatic rule numbering and renumbering
The ID automatically assigned to an ACL rule takes the nearest higher multiple of the numbering step to
the current highest rule ID, starting with 0.
For example, if the numbering step is 5 (the default), and there are five ACL rules numbered 0, 5, 9, 10,
and 12, the newly defined rule is numbered 15. If the ACL does not contain any rule, the first rule is
numbered 0.
Whenever the step changes, the rules are renumbered, starting from 0. For example, if there are five rules
numbered 5, 10, 13, 15, and 20, changing the step from 5 to 2 causes the rules to be renumbered 0, 2,
4, 6, and 8.
You cannot configure the rule number step in the Web interface. By default, the rule number step is 5.
103BImplementing time-based ACL rules
You can implement ACL rules based on the time of day by applying a time range to them. A time-based
ACL rule only takes effect in any time periods specified by the time range.
The following basic types of time range are available:
• Periodic time range—Recurs periodically on a day or days of the week.
• Absolute time range—Represents only a period of time and does not recur.