3Com 2928 User Guide - Page 452

ACL Step Currently, the Web interface does not support ACL step configuration. Meaning of the step The step defines the difference between two neighboring numbers that are automatically assigned to ACL rules by the device. For example, with a step of 5, rules are automatically numbered 0, 5, 10, 15, and so on. By default, the step is 5. Whenever the step changes, the rules are renumbered, starting from 0. For example, if four rules are numbered 0, 5, 10, and 15 respectively, changing the step from 5 to 2 will cause the rules to be renumbered 0, 2, 4, and 6. Benefits of using the step With the step and rule numbering/renumbering mechanism, you do not need to assign numbers to rules when defining them. The system will assign a newly defined rule a number that is the smallest multiple of the step bigger than the current biggest number. For example, with a step of five, if the biggest number is currently 28, the newly defined rule will get a number of 30. If the ACL has no rule defined already, the first defined rule will get a number of 0. Another benefit of using the step is that it allows you to insert new rules between existing ones as needed. For example, after creating four rules numbered 0, 5, 10, and 15 in an ACL with a step of five, you can insert a rule numbered 1. Configuring an ACL Configuration Task List Configuring an IPv4 ACL Table 1-3 lists the IPv4 ACL configuration tasks. Table 1-3 IPv4 ACL configuration task list Task Remarks Configuring a Time Range Optional A rule referencing a time range takes effect only during the specified time range. Creating an IPv4 ACL Required The category of the created ACL depends on the ACL number that you specify. Configuring a Rule for a Basic IPv4 ACL Configuring a Rule for an Advanced IPv4 ACL Configuring a Rule for an Ethernet Frame Header ACL Required Complete one of the three tasks according to the ACL category. 1-3