The Structure Rule Table

Structure Rule Table Entries

Rule Number	Superior Rule Number	Acronym of Naming Attribute	Acronym of Structural Object Class
1	0	CN	SCH
2	0	C	C
3	2	O	ORG
4	3	OU	OU
5	4	CN	ORP
6	4	CN, OU	ORP
7	4	CN	ORR
8	4	CN	MDL
9	4	CN	APP
10	9	CN	APE
11	9	CN	DSA
12	9	CN	MMS
13	9	CN	MTA
14	9	CN	MUA
15	2	L	LOC
16	15	CN	REP
17	15	CN, STA	REP

The SRT determines how the object classes are laid out in the DIT by assigning rule numbers to each object class. An object class's Superior Rule Number specifies the object class directly above it in the DIT.

For example, the object class Organization (abbreviated with the acronym ORG in the SRT) has a superior rule number of 2, indicating that it is located in the DIT beneath the object class Country (C), which has a rule number of 2. Organization Unit (OU) is located beneath Organization because it has a superior rule number of 3 and so forth.

The SRT only contains structured object classes; that is, classes that form branches in the DIT. Other object classes, such as abstract and alias classes, are not included.

The SRT specifies the attribute(s) used to name entries belonging to each object class. These attributes, called naming attributes, are used to define the RDN and therefore the distinguished name of directory entries.

The following figure shows the structure of the DIT as defined by the SRT of the GDS standard schema.

SRT DIT Structure for the GDS Standard Schema