3.1.1.4.5 Constructed Attributes
Individual constructed attributes, other than rootDSE Attributes (section 3.1.1.3.2), are specified in [MS-ADA1], [MS-ADA2], and [MS-ADA3]. But briefly, constructed attributes have the property that they are attributes for which the attribute value is computed by using other attributes, sometimes from other objects. Regardless of this property, constructed attributes are defined to be those attributes that meet one of the following three criteria:
The attributeSchema object's systemFlags attribute has the ATTR_IS_CONSTRUCTED bit (section 2.2.10) set to one.
The attribute is a rootDSE attribute (section 3.1.1.3.2).
The attribute is a back link attribute.
The objects and attributes for specified constructed attributes are covered in this section.
Except as otherwise noted, these constructed attributes are applicable to both AD DS and AD LDS.