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A Summary of the X.500(96) User Schema for use with LDAPv3
RFC 2256

Document Type RFC - Proposed Standard (December 1997)
Updated by RFC 3377
Author Mark Wahl
Last updated 2013-03-02
RFC stream Internet Engineering Task Force (IETF)
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RFC 2256
Network Working Group                                            M. Wahl
Request for Comments: 2256                           Critical Angle Inc.
Category: Standards Track                                  December 1997

       A Summary of the X.500(96) User Schema for use with LDAPv3

1. Status of this Memo

   This document specifies an Internet standards track protocol for the
   Internet community, and requests discussion and suggestions for
   improvements.  Please refer to the current edition of the "Internet
   Official Protocol Standards" (STD 1) for the standardization state
   and status of this protocol.  Distribution of this memo is unlimited.

Copyright Notice

   Copyright (C) The Internet Society (1997).  All Rights Reserved.

IESG Note

   This document describes a directory access protocol that provides
   both read and update access.  Update access requires secure
   authentication, but this document does not mandate implementation of
   any satisfactory authentication mechanisms.

   In accordance with RFC 2026, section 4.4.1, this specification is
   being approved by IESG as a Proposed Standard despite this
   limitation, for the following reasons:

   a. to encourage implementation and interoperability testing of
      these protocols (with or without update access) before they
      are deployed, and

   b. to encourage deployment and use of these protocols in read-only
      applications.  (e.g. applications where LDAPv3 is used as
      a query language for directories which are updated by some
      secure mechanism other than LDAP), and

   c. to avoid delaying the advancement and deployment of other Internet
      standards-track protocols which require the ability to query, but
      not update, LDAPv3 directory servers.

   Readers are hereby warned that until mandatory authentication
   mechanisms are standardized, clients and servers written according to
   this specification which make use of update functionality are
   UNLIKELY TO INTEROPERATE, or MAY INTEROPERATE ONLY IF AUTHENTICATION
   IS REDUCED TO AN UNACCEPTABLY WEAK LEVEL.

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   Implementors are hereby discouraged from deploying LDAPv3 clients or
   servers which implement the update functionality, until a Proposed
   Standard for mandatory authentication in LDAPv3 has been approved and
   published as an RFC.

2. Abstract

   This document provides an overview of the attribute types and object
   classes defined by the ISO and ITU-T committees in the X.500
   documents, in particular those intended for use by directory clients.
   This is the most widely used schema for LDAP/X.500 directories, and
   many other schema definitions for white pages objects use it as a
   basis.  This document does not cover attributes used for the
   administration of X.500 directory servers, nor does it include
   attributes defined by other ISO/ITU-T documents.

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED",  "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC 2119 [6].

3. General Issues

   This document references syntaxes given in section 6 of this document
   and section 6 of [1].  Matching rules are listed in section 8 of this
   document and section 8 of [1].

   The attribute type and object class definitions are written using the
   BNF form of AttributeTypeDescription and ObjectClassDescription given
   in [1].  Lines have been folded for readability.

4. Source

   The schema definitions in this document are based on those found in
   X.500 [2],[3],[4],[5], and updates to these documents, specifically:

        Sections                Source
        ============            ============
        5.1  - 5.2              X.501(93)
        5.3  - 5.36             X.520(88)
        5.37 - 5.41             X.509(93)
        5.42 - 5.52             X.520(93)
        5.53 - 5.54             X.509(96)
        5.55                    X.520(96)
        6.1                     RFC 1274
        6.2                     (new syntax)
        6.3  - 6.6              RFC 1274
        7.1  - 7.2              X.501(93)
        7.3  - 7.18             X.521(93)

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        7.19 - 7.21             X.509(96)
        7.22                    X.521(96)

   Some attribute names are different from those found in X.520(93).

   Three new attributes supportedAlgorithms, deltaRevocationList and
   dmdName, and the objectClass dmd, are defined in the X.500(96)
   documents.

5. Attribute Types

   An LDAP server implementation SHOULD recognize the attribute types
   described in this section.

5.1. objectClass

   The values of the objectClass attribute describe the kind of object
   which an entry represents.  The objectClass attribute is present in
   every entry, with at least two values.  One of the values is either
   "top" or "alias".

    ( 2.5.4.0 NAME 'objectClass' EQUALITY objectIdentifierMatch
      SYNTAX 1.3.6.1.4.1.1466.115.121.1.38 )

5.2. aliasedObjectName

   The aliasedObjectName attribute is used by the directory service if
   the entry containing this attribute is an alias.

    ( 2.5.4.1 NAME 'aliasedObjectName' EQUALITY distinguishedNameMatch
      SYNTAX 1.3.6.1.4.1.1466.115.121.1.12 SINGLE-VALUE )

5.3. knowledgeInformation

   This attribute is no longer used.

    ( 2.5.4.2 NAME 'knowledgeInformation' EQUALITY caseIgnoreMatch
      SYNTAX 1.3.6.1.4.1.1466.115.121.1.15{32768} )

5.4. cn

   This is the X.500 commonName attribute, which contains a name of an
   object.  If the object corresponds to a person, it is typically the
   person's full name.

    ( 2.5.4.3 NAME 'cn' SUP name )

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5.5. sn

   This is the X.500 surname attribute, which contains the family name
   of a person.

    ( 2.5.4.4 NAME 'sn' SUP name )

5.6. serialNumber

   This attribute contains the serial number of a device.

    ( 2.5.4.5 NAME 'serialNumber' EQUALITY caseIgnoreMatch
      SUBSTR caseIgnoreSubstringsMatch
      SYNTAX 1.3.6.1.4.1.1466.115.121.1.44{64} )

5.7. c

   This attribute contains a two-letter ISO 3166 country code
   (countryName).

    ( 2.5.4.6 NAME 'c' SUP name SINGLE-VALUE )

5.8. l

   This attribute contains the name of a locality, such as a city,
   county or other geographic region (localityName).

    ( 2.5.4.7 NAME 'l' SUP name )

5.9. st

   This attribute contains the full name of a state or province
   (stateOrProvinceName).

    ( 2.5.4.8 NAME 'st' SUP name )

5.10. street

   This attribute contains the physical address of the object to which
   the entry corresponds, such as an address for package delivery
   (streetAddress).

    ( 2.5.4.9 NAME 'street' EQUALITY caseIgnoreMatch
      SUBSTR caseIgnoreSubstringsMatch
      SYNTAX 1.3.6.1.4.1.1466.115.121.1.15{128} )

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5.11. o

   This attribute contains the name of an organization
   (organizationName).

    ( 2.5.4.10 NAME 'o' SUP name )

5.12. ou

   This attribute contains the name of an organizational unit
   (organizationalUnitName).

    ( 2.5.4.11 NAME 'ou' SUP name )

5.13. title

   This attribute contains the title, such as "Vice President", of a
   person in their organizational context.  The "personalTitle"
   attribute would be used for a person's title independent of their job
   function.

    ( 2.5.4.12 NAME 'title' SUP name )

5.14. description

   This attribute contains a human-readable description of the object.

    ( 2.5.4.13 NAME 'description' EQUALITY caseIgnoreMatch
      SUBSTR caseIgnoreSubstringsMatch
      SYNTAX 1.3.6.1.4.1.1466.115.121.1.15{1024} )

5.15. searchGuide

   This attribute is for use by X.500 clients in constructing search
   filters. It is obsoleted by enhancedSearchGuide, described below in
   5.48.

    ( 2.5.4.14 NAME 'searchGuide'
      SYNTAX 1.3.6.1.4.1.1466.115.121.1.25 )

5.16. businessCategory

   This attribute describes the kind of business performed by an
   organization.

   ( 2.5.4.15 NAME 'businessCategory' EQUALITY caseIgnoreMatch
     SUBSTR caseIgnoreSubstringsMatch
     SYNTAX 1.3.6.1.4.1.1466.115.121.1.15{128} )

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5.17. postalAddress

   ( 2.5.4.16 NAME 'postalAddress' EQUALITY caseIgnoreListMatch
     SUBSTR caseIgnoreListSubstringsMatch
     SYNTAX 1.3.6.1.4.1.1466.115.121.1.41 )

5.18. postalCode

   ( 2.5.4.17 NAME 'postalCode' EQUALITY caseIgnoreMatch
     SUBSTR caseIgnoreSubstringsMatch
     SYNTAX 1.3.6.1.4.1.1466.115.121.1.15{40} )

5.19. postOfficeBox

   ( 2.5.4.18 NAME 'postOfficeBox' EQUALITY caseIgnoreMatch
     SUBSTR caseIgnoreSubstringsMatch
     SYNTAX 1.3.6.1.4.1.1466.115.121.1.15{40} )

5.20. physicalDeliveryOfficeName

   ( 2.5.4.19 NAME 'physicalDeliveryOfficeName' EQUALITY caseIgnoreMatch
     SUBSTR caseIgnoreSubstringsMatch
     SYNTAX 1.3.6.1.4.1.1466.115.121.1.15{128} )

5.21. telephoneNumber

   ( 2.5.4.20 NAME 'telephoneNumber' EQUALITY telephoneNumberMatch
     SUBSTR telephoneNumberSubstringsMatch
     SYNTAX 1.3.6.1.4.1.1466.115.121.1.50{32} )

5.22. telexNumber

   ( 2.5.4.21 NAME 'telexNumber'
     SYNTAX 1.3.6.1.4.1.1466.115.121.1.52 )

5.23. teletexTerminalIdentifier

   ( 2.5.4.22 NAME 'teletexTerminalIdentifier'
     SYNTAX 1.3.6.1.4.1.1466.115.121.1.51 )

5.24. facsimileTelephoneNumber

   ( 2.5.4.23 NAME 'facsimileTelephoneNumber'
     SYNTAX 1.3.6.1.4.1.1466.115.121.1.22 )

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5.25. x121Address

   ( 2.5.4.24 NAME 'x121Address' EQUALITY numericStringMatch
     SUBSTR numericStringSubstringsMatch
     SYNTAX 1.3.6.1.4.1.1466.115.121.1.36{15} )

5.26. internationaliSDNNumber

   ( 2.5.4.25 NAME 'internationaliSDNNumber' EQUALITY numericStringMatch
     SUBSTR numericStringSubstringsMatch
     SYNTAX 1.3.6.1.4.1.1466.115.121.1.36{16} )

5.27. registeredAddress

   This attribute holds a postal address suitable for reception of
   telegrams or expedited documents, where it is necessary to have the
   recipient accept delivery.

    ( 2.5.4.26 NAME 'registeredAddress' SUP postalAddress
      SYNTAX 1.3.6.1.4.1.1466.115.121.1.41 )

5.28. destinationIndicator

   This attribute is used for the telegram service.

    ( 2.5.4.27 NAME 'destinationIndicator' EQUALITY caseIgnoreMatch
      SUBSTR caseIgnoreSubstringsMatch
      SYNTAX 1.3.6.1.4.1.1466.115.121.1.44{128} )

5.29. preferredDeliveryMethod

    ( 2.5.4.28 NAME 'preferredDeliveryMethod'
      SYNTAX 1.3.6.1.4.1.1466.115.121.1.14
      SINGLE-VALUE )

5.30. presentationAddress

   This attribute contains an OSI presentation address.

    ( 2.5.4.29 NAME 'presentationAddress'
      EQUALITY presentationAddressMatch
      SYNTAX 1.3.6.1.4.1.1466.115.121.1.43
      SINGLE-VALUE )

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5.31. supportedApplicationContext

   This attribute contains the identifiers of OSI application contexts.

    ( 2.5.4.30 NAME 'supportedApplicationContext'
      EQUALITY objectIdentifierMatch
      SYNTAX 1.3.6.1.4.1.1466.115.121.1.38 )

5.32. member

    ( 2.5.4.31 NAME 'member' SUP distinguishedName )

5.33. owner

    ( 2.5.4.32 NAME 'owner' SUP distinguishedName )

5.34. roleOccupant

    ( 2.5.4.33 NAME 'roleOccupant' SUP distinguishedName )

5.35. seeAlso

    ( 2.5.4.34 NAME 'seeAlso' SUP distinguishedName )

5.36. userPassword

    ( 2.5.4.35 NAME 'userPassword' EQUALITY octetStringMatch
      SYNTAX 1.3.6.1.4.1.1466.115.121.1.40{128} )

   Passwords are stored using an Octet String syntax and are not
   encrypted.  Transfer of cleartext passwords are strongly discouraged
   where the underlying transport service cannot guarantee
   confidentiality and may result in disclosure of the password to
   unauthorized parties.

5.37. userCertificate

   This attribute is to be stored and requested in the binary form, as
   'userCertificate;binary'.

    ( 2.5.4.36 NAME 'userCertificate'
      SYNTAX 1.3.6.1.4.1.1466.115.121.1.8 )

5.38. cACertificate

   This attribute is to be stored and requested in the binary form, as
   'cACertificate;binary'.

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    ( 2.5.4.37 NAME 'cACertificate'
      SYNTAX 1.3.6.1.4.1.1466.115.121.1.8 )

5.39. authorityRevocationList

   This attribute is to be stored and requested in the binary form, as
   'authorityRevocationList;binary'.

    ( 2.5.4.38 NAME 'authorityRevocationList'
      SYNTAX 1.3.6.1.4.1.1466.115.121.1.9 )

5.40. certificateRevocationList

   This attribute is to be stored and requested in the binary form, as
   'certificateRevocationList;binary'.

    ( 2.5.4.39 NAME 'certificateRevocationList'
      SYNTAX 1.3.6.1.4.1.1466.115.121.1.9 )

5.41. crossCertificatePair

   This attribute is to be stored and requested in the binary form, as
   'crossCertificatePair;binary'.

    ( 2.5.4.40 NAME 'crossCertificatePair'
      SYNTAX 1.3.6.1.4.1.1466.115.121.1.10 )

5.42. name

   The name attribute type is the attribute supertype from which string
   attribute types typically used for naming may be formed.  It is
   unlikely that values of this type itself will occur in an entry. LDAP
   server implementations which do not support attribute subtyping need
   not recognize this attribute in requests.   Client implementations
   MUST NOT assume that LDAP servers are capable of performing attribute
   subtyping.

    ( 2.5.4.41 NAME 'name' EQUALITY caseIgnoreMatch
      SUBSTR caseIgnoreSubstringsMatch
      SYNTAX 1.3.6.1.4.1.1466.115.121.1.15{32768} )

5.43. givenName

   The givenName attribute is used to hold the part of a person's name
   which is not their surname nor middle name.

    ( 2.5.4.42 NAME 'givenName' SUP name )

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5.44. initials

   The initials attribute contains the initials of some or all of an
   individuals names, but not the surname(s).

    ( 2.5.4.43 NAME 'initials' SUP name )

5.45. generationQualifier

   The generationQualifier attribute contains the part of the name which
   typically is the suffix, as in "IIIrd".

    ( 2.5.4.44 NAME 'generationQualifier' SUP name )

5.46. x500UniqueIdentifier

   The x500UniqueIdentifier attribute is used to distinguish between
   objects when a distinguished name has been reused.  This is a
   different attribute type from both the "uid" and "uniqueIdentifier"
   types.

    ( 2.5.4.45 NAME 'x500UniqueIdentifier' EQUALITY bitStringMatch
      SYNTAX 1.3.6.1.4.1.1466.115.121.1.6 )

5.47. dnQualifier

   The dnQualifier attribute type specifies disambiguating information
   to add to the relative distinguished name of an entry.  It is
   intended for use when merging data from multiple sources in order to
   prevent conflicts between entries which would otherwise have the same
   name. It is recommended that the value of the dnQualifier attribute
   be the same for all entries from a particular source.

    ( 2.5.4.46 NAME 'dnQualifier' EQUALITY caseIgnoreMatch
      ORDERING caseIgnoreOrderingMatch SUBSTR caseIgnoreSubstringsMatch
      SYNTAX 1.3.6.1.4.1.1466.115.121.1.44 )

5.48. enhancedSearchGuide

   This attribute is for use by X.500 clients in constructing search
   filters.

    ( 2.5.4.47 NAME 'enhancedSearchGuide'
      SYNTAX 1.3.6.1.4.1.1466.115.121.1.21 )

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5.49. protocolInformation

   This attribute is used in conjunction with the presentationAddress
   attribute, to provide additional information to the OSI network
   service.

    ( 2.5.4.48 NAME 'protocolInformation'
      EQUALITY protocolInformationMatch
      SYNTAX 1.3.6.1.4.1.1466.115.121.1.42 )

5.50. distinguishedName

   This attribute type is not used as the name of the object itself, but
   it is instead a base type from which attributes with DN syntax
   inherit.

   It is unlikely that values of this type itself will occur in an
   entry.  LDAP server implementations which do not support attribute
   subtyping need not recognize this attribute in requests.   Client
   implementations MUST NOT assume that LDAP servers are capable of
   performing attribute subtyping.

    ( 2.5.4.49 NAME 'distinguishedName' EQUALITY distinguishedNameMatch
      SYNTAX 1.3.6.1.4.1.1466.115.121.1.12 )

5.51. uniqueMember

    ( 2.5.4.50 NAME 'uniqueMember' EQUALITY uniqueMemberMatch
      SYNTAX 1.3.6.1.4.1.1466.115.121.1.34 )

5.52. houseIdentifier

   This attribute is used to identify a building within a location.

    ( 2.5.4.51 NAME 'houseIdentifier' EQUALITY caseIgnoreMatch
      SUBSTR caseIgnoreSubstringsMatch
      SYNTAX 1.3.6.1.4.1.1466.115.121.1.15{32768} )

5.53. supportedAlgorithms

   This attribute is to be stored and requested in the binary form, as
   'supportedAlgorithms;binary'.

    ( 2.5.4.52 NAME 'supportedAlgorithms'
      SYNTAX 1.3.6.1.4.1.1466.115.121.1.49 )

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5.54. deltaRevocationList

   This attribute is to be stored and requested in the binary form, as
   'deltaRevocationList;binary'.

    ( 2.5.4.53 NAME 'deltaRevocationList'
      SYNTAX 1.3.6.1.4.1.1466.115.121.1.9 )

5.55. dmdName

   The value of this attribute specifies a directory management domain
   (DMD), the administrative authority which operates the directory
   server.

    ( 2.5.4.54 NAME 'dmdName' SUP name )

6. Syntaxes

   Servers SHOULD recognize the syntaxes defined in this section.  Each
   syntax begins with a sample value of the ldapSyntaxes attribute which
   defines the OBJECT IDENTIFIER of the syntax.  The descriptions of
   syntax names are not carried in protocol, and are not guaranteed to
   be unique.

6.1. Delivery Method

   ( 1.3.6.1.4.1.1466.115.121.1.14 DESC 'Delivery Method' )

   Values in this syntax are encoded according to the following BNF:

      delivery-value = pdm / ( pdm whsp "$" whsp delivery-value )

      pdm = "any" / "mhs" / "physical" / "telex" / "teletex" /
                "g3fax" / "g4fax" / "ia5" / "videotex" / "telephone"

   Example:

      telephone

6.2. Enhanced Guide

   ( 1.3.6.1.4.1.1466.115.121.1.21 DESC 'Enhanced Guide' )

   Values in this syntax are encoded according to the following BNF:

      EnhancedGuide = woid whsp "#" whsp criteria whsp "#" whsp subset

      subset = "baseobject" / "oneLevel" / "wholeSubtree"

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   The criteria production is defined in the Guide syntax below.  This
   syntax has been added subsequent to RFC 1778.

   Example:

      person#(sn)#oneLevel

6.3. Guide

   ( 1.3.6.1.4.1.1466.115.121.1.25 DESC 'Guide' )

   Values in this syntax are encoded according to the following BNF:

      guide-value = [ object-class "#" ] criteria

      object-class = woid

      criteria = criteria-item / criteria-set / ( "!" criteria )

      criteria-set = ( [ "(" ] criteria "&" criteria-set [ ")" ] ) /
                     ( [ "(" ] criteria "|" criteria-set [ ")" ] )

      criteria-item = [ "(" ] attributetype "$" match-type [ ")" ]

      match-type = "EQ" / "SUBSTR" / "GE" / "LE" / "APPROX"

   This syntax should not be used for defining new attributes.

6.4. Octet String

   ( 1.3.6.1.4.1.1466.115.121.1.40 DESC 'Octet String' )

   Values in this syntax are encoded as octet strings.

   Example:

      secret

6.5. Teletex Terminal Identifier

   ( 1.3.6.1.4.1.1466.115.121.1.51 DESC 'Teletex Terminal Identifier' )

   Values in this syntax are encoded according to the following BNF:

      teletex-id = ttx-term  0*("$" ttx-param)

      ttx-term   = printablestring

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      ttx-param  = ttx-key ":" ttx-value

      ttx-key    = "graphic" / "control" / "misc" / "page" / "private"

      ttx-value  = octetstring

   In the above, the first printablestring is the encoding of the first
   portion of the teletex terminal identifier to be encoded, and the
   subsequent 0 or more octetstrings are subsequent portions of the
   teletex terminal identifier.

6.6. Telex Number

   ( 1.3.6.1.4.1.1466.115.121.1.52 DESC 'Telex Number' )

   Values in this syntax are encoded according to the following BNF:

      telex-number  = actual-number "$" country "$" answerback

      actual-number = printablestring

      country       = printablestring

      answerback    = printablestring

   In the above, actual-number is the syntactic representation of the
   number portion of the TELEX number being encoded, country is the
   TELEX country code, and answerback is the answerback code of a TELEX
   terminal.

6.7. Supported Algorithm

   ( 1.3.6.1.4.1.1466.115.121.1.49 DESC 'Supported Algorithm' )

   No printable representation of values of the supportedAlgorithms
   attribute is defined in this document.  Clients which wish to store
   and retrieve this attribute MUST use "supportedAlgorithms;binary", in
   which the value is transferred as a binary encoding.

7. Object Classes

   LDAP servers MUST recognize the object classes "top" and "subschema".
   LDAP servers SHOULD recognize all the other object classes listed
   here as values of the objectClass attribute.

7.1. top

   ( 2.5.6.0 NAME 'top' ABSTRACT MUST objectClass )

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7.2. alias

   ( 2.5.6.1 NAME 'alias' SUP top STRUCTURAL MUST aliasedObjectName )

7.3. country

   ( 2.5.6.2 NAME 'country' SUP top STRUCTURAL MUST c
     MAY ( searchGuide $ description ) )

7.4. locality

   ( 2.5.6.3 NAME 'locality' SUP top STRUCTURAL
     MAY ( street $ seeAlso $ searchGuide $ st $ l $ description ) )

7.5. organization

   ( 2.5.6.4 NAME 'organization' SUP top STRUCTURAL MUST o
     MAY ( userPassword $ searchGuide $ seeAlso $ businessCategory $
     x121Address $ registeredAddress $ destinationIndicator $
     preferredDeliveryMethod $ telexNumber $ teletexTerminalIdentifier $
     telephoneNumber $ internationaliSDNNumber $
     facsimileTelephoneNumber $
     street $ postOfficeBox $ postalCode $ postalAddress $
     physicalDeliveryOfficeName $ st $ l $ description ) )

7.6. organizationalUnit

   ( 2.5.6.5 NAME 'organizationalUnit' SUP top STRUCTURAL MUST ou
     MAY ( userPassword $ searchGuide $ seeAlso $ businessCategory $
     x121Address $ registeredAddress $ destinationIndicator $
     preferredDeliveryMethod $ telexNumber $ teletexTerminalIdentifier $
     telephoneNumber $ internationaliSDNNumber $
     facsimileTelephoneNumber $
     street $ postOfficeBox $ postalCode $ postalAddress $
     physicalDeliveryOfficeName $ st $ l $ description ) )

7.7. person

   ( 2.5.6.6 NAME 'person' SUP top STRUCTURAL MUST ( sn $ cn )
     MAY ( userPassword $ telephoneNumber $ seeAlso $ description ) )

7.8. organizationalPerson

   ( 2.5.6.7 NAME 'organizationalPerson' SUP person STRUCTURAL
     MAY ( title $ x121Address $ registeredAddress $
     destinationIndicator $
     preferredDeliveryMethod $ telexNumber $ teletexTerminalIdentifier $
     telephoneNumber $ internationaliSDNNumber $

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     facsimileTelephoneNumber $
     street $ postOfficeBox $ postalCode $ postalAddress $
     physicalDeliveryOfficeName $ ou $ st $ l ) )

7.9. organizationalRole

   ( 2.5.6.8 NAME 'organizationalRole' SUP top STRUCTURAL MUST cn
     MAY ( x121Address $ registeredAddress $ destinationIndicator $
     preferredDeliveryMethod $ telexNumber $ teletexTerminalIdentifier $
     telephoneNumber $ internationaliSDNNumber $
     facsimileTelephoneNumber $
     seeAlso $ roleOccupant $ preferredDeliveryMethod $ street $
     postOfficeBox $ postalCode $ postalAddress $
     physicalDeliveryOfficeName $ ou $ st $ l $ description ) )

7.10. groupOfNames

   ( 2.5.6.9 NAME 'groupOfNames' SUP top STRUCTURAL MUST ( member $ cn )
     MAY ( businessCategory $ seeAlso $ owner $ ou $ o $ description ) )

7.11. residentialPerson

   ( 2.5.6.10 NAME 'residentialPerson' SUP person STRUCTURAL MUST l
     MAY ( businessCategory $ x121Address $ registeredAddress $
     destinationIndicator $ preferredDeliveryMethod $ telexNumber $
     teletexTerminalIdentifier $ telephoneNumber $
     internationaliSDNNumber $
     facsimileTelephoneNumber $ preferredDeliveryMethod $ street $
     postOfficeBox $ postalCode $ postalAddress $
     physicalDeliveryOfficeName $ st $ l ) )

7.12. applicationProcess

   ( 2.5.6.11 NAME 'applicationProcess' SUP top STRUCTURAL MUST cn
     MAY ( seeAlso $ ou $ l $ description ) )

7.13. applicationEntity

   ( 2.5.6.12 NAME 'applicationEntity' SUP top STRUCTURAL
     MUST ( presentationAddress $ cn )
     MAY ( supportedApplicationContext $ seeAlso $ ou $ o $ l $
     description ) )

7.14. dSA

   ( 2.5.6.13 NAME 'dSA' SUP applicationEntity STRUCTURAL
     MAY knowledgeInformation )

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7.15. device

   ( 2.5.6.14 NAME 'device' SUP top STRUCTURAL MUST cn
     MAY ( serialNumber $ seeAlso $ owner $ ou $ o $ l $ description ) )

7.16. strongAuthenticationUser

   ( 2.5.6.15 NAME 'strongAuthenticationUser' SUP top AUXILIARY
     MUST userCertificate )

7.17. certificationAuthority

   ( 2.5.6.16 NAME 'certificationAuthority' SUP top AUXILIARY
     MUST ( authorityRevocationList $ certificateRevocationList $
     cACertificate ) MAY crossCertificatePair )

7.18. groupOfUniqueNames

   ( 2.5.6.17 NAME 'groupOfUniqueNames' SUP top STRUCTURAL
     MUST ( uniqueMember $ cn )
     MAY ( businessCategory $ seeAlso $ owner $ ou $ o $ description ) )

7.19. userSecurityInformation

   ( 2.5.6.18 NAME 'userSecurityInformation' SUP top AUXILIARY
     MAY ( supportedAlgorithms ) )

7.20. certificationAuthority-V2

   ( 2.5.6.16.2 NAME 'certificationAuthority-V2' SUP
     certificationAuthority
     AUXILIARY MAY ( deltaRevocationList ) )

7.21. cRLDistributionPoint

   ( 2.5.6.19 NAME 'cRLDistributionPoint' SUP top STRUCTURAL
     MUST ( cn ) MAY ( certificateRevocationList $
     authorityRevocationList $
     deltaRevocationList ) )

7.22. dmd

   ( 2.5.6.20 NAME 'dmd' SUP top STRUCTURAL MUST ( dmdName )
     MAY ( userPassword $ searchGuide $ seeAlso $ businessCategory $
     x121Address $ registeredAddress $ destinationIndicator $
     preferredDeliveryMethod $ telexNumber $ teletexTerminalIdentifier $
     telephoneNumber $ internationaliSDNNumber $
     facsimileTelephoneNumber $

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     street $ postOfficeBox $ postalCode $ postalAddress $
     physicalDeliveryOfficeName $ st $ l $ description ) )

8. Matching Rules

   Servers MAY implement additional matching rules.

8.1. octetStringMatch

   Servers which implement the extensibleMatch filter SHOULD allow the
   matching rule listed in this section to be used in the
   extensibleMatch.  In general these servers SHOULD allow matching
   rules to be used with all attribute types known to the server, when
   the assertion syntax of the matching rule is the same as the value
   syntax of the attribute.

   ( 2.5.13.17 NAME 'octetStringMatch'
    SYNTAX 1.3.6.1.4.1.1466.115.121.1.40 )

9. Security Considerations

   Attributes of directory entries are used to provide descriptive
   information about the real-world objects they represent, which can be
   people, organizations or devices.  Most countries have privacy laws
   regarding the publication of information about people.

   Transfer of cleartext passwords are strongly discouraged where the
   underlying transport service cannot guarantee confidentiality and may
   result in disclosure of the password to unauthorized parties.

10. Acknowledgements

   The definitions on which this document have been developed by
   committees for telecommunications and international standards.  No
   new attribute definitions have been added.  The syntax definitions
   are based on the ISODE "QUIPU" implementation of X.500.

11. Bibliography

   [1] Wahl, M., Coulbeck, A., Howes, T., and S. Kille,
       "Lightweight X.500 Directory Access Protocol (v3): Attribute
       Syntax Definitions", RFC 2252, December 1997.

   [2] The Directory: Models. ITU-T Recommendation X.501, 1996.

   [3] The Directory: Authentication Framework. ITU-T Recommendation
       X.509, 1996.

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   [4] The Directory: Selected Attribute Types. ITU-T Recommendation
       X.520, 1996.

   [5] The Directory: Selected Object Classes.  ITU-T Recommendation
       X.521, 1996.

   [6] Bradner, S., "Key words for use in RFCs to Indicate Requirement
       Levels", RFC 2119, March 1997.

12. Author's Address

   Mark Wahl
   Critical Angle Inc.
   4815 West Braker Lane #502-385
   Austin, TX 78759
   USA

   Phone:  +1 512 372 3160
   EMail:  M.Wahl@critical-angle.com

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13.  Full Copyright Statement

   Copyright (C) The Internet Society (1997).  All Rights Reserved.

   This document and translations of it may be copied and furnished to
   others, and derivative works that comment on or otherwise explain it
   or assist in its implementation may be prepared, copied, published
   and distributed, in whole or in part, without restriction of any
   kind, provided that the above copyright notice and this paragraph are
   included on all such copies and derivative works.  However, this
   document itself may not be modified in any way, such as by removing
   the copyright notice or references to the Internet Society or other
   Internet organizations, except as needed for the purpose of
   developing Internet standards in which case the procedures for
   copyrights defined in the Internet Standards process must be
   followed, or as required to translate it into languages other than
   English.

   The limited permissions granted above are perpetual and will not be
   revoked by the Internet Society or its successors or assigns.

   This document and the information contained herein is provided on an
   "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
   TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
   BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
   HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

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