Representing Tables and Subtrees in the X.500 Directory
obsoletes
- rfc-1837 — Representing Tables and Subtrees in the X.500 Directory
Extracted elements (15)
A subtree is functionally equivalent to a table with distinguished name keys, but the subtree approach constructs keys as a DN hierarchy relative to the subtree root rather than as flat entries, making it preferable when the subtree is more populated.
A table is used when the key cannot be represented as a global name, for reasons including: the object lacks a natural global name, the name is only meaningful in the context of the binding, there is no authority to place parameters in the global entry, or grouping information together is a performance optimization for replication.
No specific object classes for subtree entries are defined because information within the subtree is generally defined in the same way as for the corresponding global objects, so the global object classes suffice.
The DistinguishedNameTableEntry approach should be used when the number of objects is small or sparsely spread over the DIT; the subtree approach defined in Section 2 is preferable when there are many objects or they are tightly clustered, since the subtree is better for more populated trees.
This document obsoletes RFC 1837 and was developed for supporting MHS use of Directory (RFC 1801), but the table and subtree techniques are specified separately due to their more general applicability beyond MHS.
Object identifiers for all object classes and attributes are assigned under the mhs-ds arc: {iso(1) org(3) dod(6) internet(1) private(4) enterprises(1) isode-consortium(453) mhs-ds(7) tables(1)}. Object classes use {oc} sub-arc and attributes use {at} sub-arc.
The 'distinguishedNameTableEntry' object class is a subclass of tableEntry and must contain distinguishedNameTableKey. It is used to associate information with globally named objects using their DN as the table key.
The 'distinguishedNameTableKey' attribute is a subtype of distinguishedName and serves as the naming attribute (RDN) for distinguishedNameTableEntry instances.
The 'subtree' object class is a subclass of 'top', must contain commonName, and may contain manager. It defines the root entry for a directory subtree used to associate local information with global DIT objects.
The 'table' object class is a subclass of 'top', must contain commonName, and may contain manager. It represents the root entry of a flat table in the X.500 Directory.
The 'tableEntry' object class is a subclass of 'top' and may contain description. It is a generic base class for all table entries and must be subclassed to define the naming attribute.
The 'textTableEntry' object class is a subclass of tableEntry, must contain textTableKey, and may contain textTableValue. It supports text key to text value (or other typed value) mappings.
The 'textTableKey' attribute is a subtype of name with syntax DirectoryString {ub-name}, used as the RDN/key in a textTableEntry.
The 'textTableValue' attribute is a subtype of name with syntax DirectoryString {ub-description}, providing a text value associated with a textTableKey.
Security considerations are not discussed in this memo.