Apple Network Setup - Manual (Page 16)

C H A P T E R 1
About Network Setup
16 Network Setup Database Fundamentals
Network Setup Database Fundamentals 1
This section describes the fundamental structure of and operations on the
Network Setup database.
Database Structure 1
The Network Setup database consists of multiple areas. There are two types of
areas:
named areas store preferences, while temporary areas are used as part of
the preference modification process. The system currently uses a single named
area, known as the
default area (sometimes referred to as the current area ) to
store all network preferences. While it is possible to create and manipulate other
named areas within the database, doing so does not affect any network settings.
Areas are identified by a unique
area ID .
Each area contains a number of entities having the following properties:
■ entity reference. An entity reference uniquely identifies an entity. The entity
reference contains an area ID, which identifies the area in which the entity
resides.
■ entity name. A user-visible name for the entity that need not be unique.
■ entity class and type. These values, both of type OSType , determine the type
of data contained within an entity. There are three entity classes:
■ network connection entity. A network connection entity contains
information about a single instance of a network protocol on a port.
Typically there is one active network connection entity per protocol stack,
but on a multihomed computer there can be more. The entity type for an
network connection entity indicates the network protocol of the
connection.
■ global protocol entity. A global protocol entity contains configuration for
a protocol stack on a computer. There is only one active global protocol
entity for each protocol stack. The entity type for a global protocol entity
indicates the network protocol whose configuration it contains.
■ set entity. A set entity groups global protocol and network connection
entities into a set. The set entity contains entity references to each entity in
the set. An area can contain multiple set entities, but there is one and only