The Shared Profile Components section enables you to develop and name
reusable, shared sets of authorization components that may be applied to one or
more users or groups of users and referenced by name within their profiles. These
include network access filters (NAFs), downloadable IP access control lists
(ACLs), network access restrictions (NARs), and command authorization sets.

The Shared Profile Components section addresses the scalability of selective
authorization. Shared profile components can be configured once and then applied
to many users or groups. Without this ability, flexible and comprehensive
authorization could only be accomplished by explicitly configuring the
authorization of each user group on each device. Creating and applying these