3 - Administrative Model
The Administrative Model is a really critical notion that needs to be understood, because it drives many of ApacheDS roles.
It’s directly inherited by the X.500 Administrative model (in fact, we do implement the full X.500 specification related to AAs).
What is the Administrative Model ?
The idea is to define the DIT as some areas which are administered. Each area can be defined, and covers a set of entries, and each area can manage one ore more roles we want to manage. Those roles can be related to authorization, schema, etc… Each of these areas can overlap, but in any case, if two areas are overlapping, then one area totally includes the other one.
The Administrative Model is everything we need to implement in order to be able to manage roles on some defined areas.
An Area describes a part of the DIT which will start from a specific entry, and spans across a part of the subtree starting at the base entry. An area is administered by an AP (Administrative Point) which holds all the needed information about the area and the roles.
We have three kind of areas :
- AAA : Autonomous Administrative Areas
- SAA : Specific Administrative Areas
- IAA : Inner Administrative Areas
AAAs cover all the roles as if we had declared one SAA for each existing role. They overload any area in which they can be encapsulated, hiding them.
SAAs cover one specific role, and overload any encapsulating area with the same role.
IAAs cover one specific role, but don’t not overload any encapsulating area with the same role.
An Administration Point is the point in the DIT where an area starts. It defines the roles, and the scope that applies to this area.
Once we know which area we need to define, and the associated roles, it’s mandatory to store those information in the DIT. This is done by adding subentries, which just are entries storing all the administrative configuration.
An Administrative Point is stored as a subentry (which is just a plain LDAP entry) just below the base of the defined area.
The roles are the various aspects which are managed by the administration points. Currently, we manage five different roles in ApacheDS :
- Authorization : manage the access to entries
- Schema : define the schema to be used by a subtree
- Triggers : define the triggers that can be leveraged in a subtree
- Collective Attributes : manage attributes that are valid ofr a set of entries
- Replication : manage the replication of a set
ApacheDS 2.0 coverage
Currently, in Apache 2.0, we don’t implement all this model. What is supported is :
- AAA and SAA : We don’t currently support IAA
- We don’t have more than one schema
- Replication is not managed with any administration point
Those missing parts will be implemented in the forthcoming versions.