An access list sequence number is a number at the beginning of a
command in an access list. The sequence number determines the order that the entry appears in the access list. The ability
to apply sequence numbers to IP access list entries simplifies access list changes.
Prior to having sequence numbers, users could only add access list entries to the end of an access list; therefore, needing
to add statements anywhere except the end of the list required reconfiguring the entire access list. There was no way to specify
the position of an entry within an access list. If a user wanted to insert an entry (statement) in the middle of an existing
list, all of the entries after the desired position had to be removed, then the new entry was added, and then all the removed
entries had to be reentered. This method was cumbersome and error prone.
This feature allows users to add sequence numbers to access list entries and resequence them. When a user adds a new entry,
the user chooses the sequence number so that it is in a desired position in the access list. If necessary, entries currently
in the access list can be resequenced to create room to insert the new entry. Sequence numbers make revising an access list