Network Working                                             S.E. Kille
Group                                                       Isode Ltd.
INTERNET-DRAFT                                             August 1997
Obsoletes:  RFC 1836                              Expires:  April 1998
                                                                 File:
                                      draft-ietf-mixer-infotree-00.txt


            Representing the O/R Address hierarchy in the
                   X.500 Directory Information Tree



Status of this Memo

This document is an Internet Draft.  Internet Drafts are working
documents of the Internet Engineering Task Force (IETF), its Areas,
and its Working Groups.  Note that other groups may also distribute
working documents as Internet Drafts.
Internet Drafts are draft documents valid for a maximum of six months.
Internet Drafts may be updated, replaced, or obsoleted by other
documents at any time.  It is not appropriate to use Internet Drafts
as reference material or to cite them other than as a ``working
draft'' or ``work in progress.''
Please check the I-D abstract listing contained in each Internet Draft
directory to learn the current status of this or any other Internet
Draft.

Abstract
This document defines a representation of the O/R Address hierarchy in
the Directory Information Tree [6, 1].  This is useful for a range of
purposes, including:


 o  Support for MHS Routing [4].

 o  Support for X.400/RFC 822 address mappings [2, 5].

This draft document will be submitted to the RFC editor as a protocol
standard.  Distribution of this memo is unlimited.  Please send
comments to the author or to the discussion group
<mhs-ds@mercury.udev.cdc.com>.




INTERNET--DRAFT          O/R Addresses in the DIT          August 1997



                _Object_Class_______________Mandatory_
                 mHSCountry                 M
                 aDMD                       M
                 pRMD                       O
                 mHSX121                    O
                 mHSNumericUserIdentifier   O
                 mHSOrganization            O
                 mHSOrganizationalUnit      O
                 mHSPerson                  O
                 mHSNamedObject             O
                 mHSTerminalID              O
                 mHSDomainDefinedAttribute  O

         Table 1:  Order of O/R Address Directory Components



1  The O/R Address Hierarchy

An O/R Address hierarchy is represented in the X.500 directory by
associating directory name components with O/R Address components.  An
example of this is given in Figure 1.  The object classes and
attributes required to support this representation are defined in
Figure 2.  The schema, which defines the hierarchy in which these
objects are represented in the directory information tree is specified
in Table 1.  A given object class defined in the table will always be
higher in the DIT than an object class defined lower down the table.
Valid combinations of O/R Address components are defined in X.400.
















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                               @ @

                 C=GB             @ @  Numeric-C=234
                                     @ @

             ___________________________@R_oeS.............
             | Country    |              _____S

             |__aeaeHH___ |
             aaee     H H H  ADMD=Gold 400
  ADMD=" "aaee             H H H
________aeae=_            ______H_HHj_

|ADMD       |             | ADMD       |

|____Q_Q_Q__|             |_____@@____ |

          Q QQPRMD=UK.AC           @ @ PRMD=UK.AC
             __Q_QQs_____             @ @

             |  PRMD     ________________@@R_oe_SS.............|

             |___________ |

              O=UCL
  ____________

  | MHS-Org    |

  |______Q_Q__ |
            Q Q
               Q QOU=CS
                   QQ
                 _____QQs____

                 | MHS-OU     |
                 |___________ |

                 Figure 1:  Example O/R Address Tree




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_______________________________________________________________________
IMPORTS
  ub-domain-name-length, ub-organization-name-length,
  ub-organizational-unit-name-length, ub-common-name-length,
  ub-x121-address-length, ub-domain-defined-attribute-type-length,
  ub-domain-defined-attribute-value-length, ub-terminal-id-length,
  ub-numeric-user-id-length, ub-country-name-numeric-length,
  ub-surname-length, ub-given-name-length,  ub-initials-length,
  ub-generation-qualifier-length

    FROM MTSUpperBounds {joint-iso-ccitt mhs-motis(6) mts(3)        10
        modules(0) upper-bounds(3) };

mHSCountry OBJECT-CLASS ::= {
    SUBCLASS OF {country}
    MAY CONTAIN {mHSNumericCountryName}
    ID oc-mhs-country}

mHSNumericCountryName ATTRIBUTE ::= {
    WITH SYNTAX NumericString (SIZE (1..ub-country-name-numeric-length))
    SINGLE VALUE                                                    20
    ID at-mhs-numeric-country-name}

aDMD OBJECT-CLASS ::= {
    SUBCLASS OF {top}
    MUST CONTAIN {aDMDName}
    ID oc-admd}

aDMDName ATTRIBUTE ::= {
    SUBTYPE OF name
    WITH SYNTAX DirectoryString {ub-domain-name-length}             30
    ID at-admd-name}

pRMD OBJECT-CLASS ::= {
    SUBCLASS OF {top}
    MUST CONTAIN {pRMDName}
    ID oc-prmd}

pRMDName ATTRIBUTE ::= {
    SUBTYPE OF name
    WITH SYNTAX DirectoryString {ub-domain-name-length}             40
    ID at-prmd-name}



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mHSOrganization OBJECT-CLASS ::= {
    SUBCLASS OF {top}
    MUST CONTAIN {mHSOrganizationName }
    ID oc-mhs-organization}

mHSOrganizationName ATTRIBUTE ::= {
    SUBTYPE OF organizationName
    WITH SYNTAX DirectoryString {ub-organization-name-length}       50
    ID at-mhs-organization-name}


mHSOrganizationalUnit OBJECT-CLASS ::= {
    SUBCLASS OF {top}
    MUST CONTAIN {mHSOrganizationalUnitName}
    ID oc-mhs-organizational-unit}

mHSOrganizationalUnitName ATTRIBUTE ::= {
    SUBTYPE OF organizationalUnitName                               60
    WITH SYNTAX DirectoryString {ub-organizational-unit-name-length}
    ID at-mhs-organizational-unit-name}

mHSPerson OBJECT-CLASS ::= {
    SUBCLASS OF {top}
    MUST CONTAIN {mHSSurname}
    MAY CONTAIN {mHSGivenName|
                mHSInitials|
                mHSGenerationalQualifier}
    ID oc-mhs-person}                                               70

mHSSurname ATTRIBUTE ::= {
    SUBTYPE OF surname
    WITH SYNTAX DirectoryString {ub-surname-lenght}
    ID at-mhs-surname}

mHSGivenName ATTRIBUTE ::= {
    SUBTYPE OF givenName
    WITH SYNTAX DirectoryString {ub-given-name-length}
    ID at-mhs-given-name}                                           80

mHSInitials ATTRIBUTE ::= {
    SUBTYPE OF initials
    WITH SYNTAX DirectoryString {ub-initials-length}
    ID at-mhs-initials}


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mHSGenerationQualifier ATTRIBUTE ::= {
    SUBTYPE OF generationQualifier
    WITH SYNTAX DirectoryString {ub-generation-qualifier-length}
    ID at-mhs-generation-qualifier}                                 90

mHSNamedObject OBJECT-CLASS ::= {
    SUBCLASS OF {top}
    MUST CONTAIN {mHSCommonName}
    ID oc-mhs-named-object}

mHSCommonName ATTRIBUTE ::= {
    SUBTYPE OF commonName
    WITH SYNTAX DirectoryString {ub-common-name-length}
    ID at-mhs-common-name}                                         100

mHSX121 OBJECT-CLASS ::= {
    SUBCLASS OF {top}
    MUST CONTAIN {mHSX121Address}
    ID oc-mhs-x121}

mHSX121Address ATTRIBUTE ::= {
    SUBTYPE OF name
    WITH SYNTAX DirectoryString {ub-x121-address-length}
    ID at-x121-address}                                            110

mHSDomainDefinedAttribute OBJECT-CLASS ::= {
    SUBCLASS OF {top}
    MUST CONTAIN {
        mHSDomainDefinedAttributeType|
        mHSDomainDefinedAttributeValue}
    ID oc-mhs-domain-defined-attribute}

mHSDomainDefinedAttributeType ATTRIBUTE ::= {
    SUBTYPE OF name                                                120
    WITH SYNTAX DirectoryString {ub-domain-defined-attribute-type-length}
    SINGLE VALUE
    ID at-mhs-domain-defined-attribute-type}

mHSDomainDefinedAttributeValue ATTRIBUTE ::= {
    SUBTYPE OF name
    WITH SYNTAX DirectoryString {ub-domain-defined-attribute-value-length}
    SINGLE VALUE
    ID at-mhs-domain-defined-attribute-value}
                                                                   130

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mHSTerminalID OBJECT-CLASS ::= {
    SUBCLASS OF {top}
    MUST CONTAIN {mHSTerminalIDName}
    ID oc-mhs-terminal-id}

mHSTerminalIDName ATTRIBUTE ::= {
    SUBTYPE OF name
    WITH SYNTAX DirectoryString {ub-terminal-id-length}
    ID at-mhs-terminal-id-name}                                    140


mHSNumericUserIdentifier OBJECT-CLASS ::= {
    SUBCLASS OF {top}
    MUST CONTAIN {mHSNumericUserIdentifierName}
    ID oc-mhs-numeric-user-id}

mHSNumericeUserIdentifierName ATTRIBUTE ::= {
    SUBTYPE OF name
    WITH SYNTAX DirectoryString {ub-numeric-user-id-length}        150
    ID at-mhs-numeric-user-id-name}

___________________Figure_2:__O/R_Address_Hierarchy____________________

The hierarchy is defined so that:


1.  The representation is defined so that it is straightforward to
    make a mechanical transformation in either direction.  This
    requires that each node is named by an attribute whose type can
    determine the mapping.

2.  Where there are multiple domain defined attributes, the first in
    the sequence is the most significant.

3.  Physical Delivery (postal) addresses are not represented in this
    hierarchy.  This is primarily because physical delivery can be
    handled by the Access Unit routing mechanisms defined in [4], and
    there is no need for this representation.

4.  Terminal and network forms of address are not handled, except for
    X.121 form, which is useful for addressing faxes.

5.  MHSCountry is defined as a subclass of Country, and so the same

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    entry will be used for MHS Routing as for the rest of the DIT.

6.  The numeric country code will be an alias.

7.  ADMD will always be present in the hierarchy.  This is true in the
    case of `` '' and of ``0''.  This facilitates an easy mechanical
    transformation between the two forms of address.

8.  Each node is named by the relevant part of the O/R Address.

9.  Aliases may be used in other parts of the tree, in order to
    normalise alternate values.  Where an alias is used, the value of
    the alias should be present as an alternate value in the node
    aliased to.  Aliases may not be used for domain defined
    attributes.

10. Domain Defined Attributes are named by a multi-valued RDN
    (Relative Distinguished Name), consisting of the type and value.
    This is done so that standard attribute syntaxes can be used.

11. Where an O/R Address has a valid Printable String and T.61 form,
    both must be present, with one as an alias for the other.  This is
    so that direct lookup of the name will work, independent of the
    variant used.  When both are present in an O/R Address being
    looked up, either may be used to construct the distinguished name.

12. Personal name is handled by use of the mHSPerson object class.
    Each of the components of the personal name will be present in the
    relative distinguished name, which will usually be multi-valued.

The relationship between X.400 O/R Addresses and the X.400 Entries
(Attribute Type and Object Class) are given in Table 2.  Where there
are multiple Organizational Units or Domain Defined Attributes, each
component is mapped onto a single X.500 entry.


Note: When an X.121 address is used for addressing fax transmission,
    this may only be done relative to the PRMD or ADMD. This is in
    line with the current X.400 standards position.  This means that
    it is not possible to use this form of addressing for an
    organisational or departmental fax gateway service.




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O/R_Address__Object_Class_______________Naming_Attribute________________
C            mHSCountry                 countryName
                                        or
                                        mHSNumericCountryName
A            aDMD                       aDMDName
P            pRMD                       pRMDName
O            mHSOrganization            mHSOrganizationName
OU/OU1/OU2   mHSOrganizationalUnit      mHSOrganizationalUnitName
OU3/OU4
PN           mHSPerson                  personName
CN           mHSNamedObject             mHSCommonName
X121         mHSX121                    mHSX121Address
T-ID         mHSTerminalID              mHSTerminalIDName
UA-ID        mHSNumericUserIdentifier   mHSNumericUserIdentifierName
DDA          mHSDomainDefinedAttribute  mHSDomainDefinedAttributeType
                                        and
                                        mHSDomainDefinedAttributeValue


         Table 2:  O/R Address relationship to Directory Name


2  Notation

O/R Addresses are written in the standard X.400 Notation.
Distinguished Names use the string representation of distinguished
names defined in [3].  The keywords used for the attributes defined in
this specification are given in Table 3.


3  Example Representation


The O/R Address:

I=S; S=Kille; OU1=CS; O=UCL,
P=UK.AC; A=Gold 400; C=GB;


would be represented in the directory as:

MHS-I=S + MHS-S=Kille, MHS-OU=CS, MHS-O=UCL,


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        _Attribute_______________________Keyword_____________
         mHSNumericCountryName           MHS-Numeric-Country
         aDMDName                        ADMD
         pRMDName                        PRMD
         mHSOrganizationName             MHS-O
         mHSOrganizationalUnitName       MHS-OU
         mHSSurname                      MHS-S
         mHSGivenName                    MHS-G
         mHSInitials                     MHS-I
         mHSGenerationalQualifier        MHS-GQ
         mHSCommonName                   MHS-CN
         mHSX121Address                  MHS-X121
         mHSDomainDefinedAttributeType   MHS-DDA-Type
         mHSDomainDefinedAttributeValue  MHS-DDA-Value
         mHSTerminalIDName               MHS-T-ID
         mHSNumericeUserIdentifierName   MHS-UA-ID

           Table 3:  Keywords for String DN Representation


PRMD=UK.AC, ADMD=Gold 400, C=GB


4  Mapping from O/R Address to Directory Name


The primary application of this mapping is to take an X.400 encoded
O/R Address and to generate an equivalent directory name.  This
mapping is only used for selected types of O/R Address:

 o  Mnemonic form

 o  Numeric form

 o  Terminal form, where country is present and X121 addressing is
    used


Other forms of O/R address are handled by Access Unit mechanisms.
The O/R Address is treated as an ordered list, with the order as
defined in Table 1.  For each O/R Address attribute, generate the
equivalent directory naming attribute.  In most cases, the mapping is


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mechanical.  Printable String or Teletex encodings are chosen as
appropriate.  Where both forms are present in the O/R Address, either
form may be used to generate the distinguished name.  Both will be
represented in the DIT. There are two special cases:

1.  A DDA generates a multi-valued RDN

2.  The Personal Name is mapped to a multi-valued RDN


In many cases, an O/R Address will be provided, and only the higher
components of the address will be represented in the DIT. In this
case, the ``longest possible match'' should be returned.


5  Mapping from Directory Name to O/R Address

The reverse mapping is also needed in some cases.  All of the naming
attributes are unique, so the mapping is mechanically reversible.


6  Acknowledgements

Acknowledgements for work on this document are given in [4].


References

[1] The Directory --- overview of concepts, models and services,
    1993. CCITT X.500 Series Recommendations.

[2] S.E. Kille. Mapping between X.400(1988) / ISO 10021 and RFC 822.
    Request for Comments 1327, Department of Computer Science,
    University College London, May 1992.

[3] S.E. Kille. A string representation of distinguished name.
    Request for Comments 1485, Department of Computer Science,
    University College London, January 1992.

[4] S.E. Kille. Use of the X.500 directory to support mapping between
    X.400 and RFC 822 addresses, September 1994. Internet Draft.

[5] S.E. Kille. X.400-MHS use of the X.500 directory to support


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INTERNET--DRAFT          O/R Addresses in the DIT          August 1997


    X.400-MHS routing. Request for Comments RFC 1801, Isode Ltd.,
    June 1995.

[6] CCITT recommendations X.400 / ISO 10021, April 1988. CCITT
    SG 5/VII / ISO/IEC JTC1, Message Handling:  System and Service
    Overview.


7  Security Considerations

Security considerations are not discussed in this INTERNET--DRAFT.


8  Author's Address

    Steve Kille
    Isode Ltd.
    The Dome
    The Square
    Richmond
    TW9 1DT
    England


    Phone:  +44-181-332-9091

    Internet EMail:  S.Kille@ISODE.COM


    X.400:  I=S; S=Kille; P=ISODE; A=Mailnet; C=FI;















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A  Object Identifier Assignment












































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_______________________________________________________________________
mhs-ds OBJECT IDENTIFIER ::= {iso(1) org(3) dod(6) internet(1) private(4)
          enterprises(1) isode-consortium (453) mhs-ds (7)}


tree OBJECT IDENTIFIER ::= {mhs-ds 2}

oc OBJECT IDENTIFIER ::= {tree 1}
at OBJECT IDENTIFIER ::= {tree 2}

oc-admd OBJECT IDENTIFIER ::= {oc 1}                                10
oc-mhs-country OBJECT IDENTIFIER ::= {oc 2}
oc-mhs-domain-defined-attribute OBJECT IDENTIFIER ::= {oc 3}
oc-mhs-named-object OBJECT IDENTIFIER ::= {oc 4}
oc-mhs-organization OBJECT IDENTIFIER ::= {oc 5}
oc-mhs-organizational-unit OBJECT IDENTIFIER ::= {oc 6}
oc-mhs-person OBJECT IDENTIFIER ::= {oc 7}
oc-mhs-x121 OBJECT IDENTIFIER ::= {oc 8}
oc-prmd OBJECT IDENTIFIER ::= {oc 9}
oc-mhs-terminal-id OBJECT IDENTIFIER ::= {oc 10}
oc-mhs-numeric-user-id OBJECT IDENTIFIER ::= {oc 11}                20

at-admd-name OBJECT IDENTIFIER ::= {at 1}
at-mhs-common-name OBJECT IDENTIFIER ::= {at 2}
at-mhs-domain-defined-attribute-type OBJECT IDENTIFIER ::= {at 3}
at-mhs-domain-defined-attribute-value OBJECT IDENTIFIER ::= {at 4}
at-mhs-numeric-country-name OBJECT IDENTIFIER ::= {at 5}
at-mhs-organization-name OBJECT IDENTIFIER ::= {at 6}
at-mhs-organizational-unit-name OBJECT IDENTIFIER ::= {at 7}
at-prmd-name OBJECT IDENTIFIER ::= {at 10}
at-x121-address OBJECT IDENTIFIER ::= {at 12}                       30
at-mhs-terminal-id-name OBJECT IDENTIFIER ::= {at 13}
at-mhs-numeric-user-id-name  OBJECT IDENTIFIER ::= {at 14}
at-mhs-surname OBJECT IDENTIFIER ::= {at 15}
at-mhs-given-name OBJECT IDENTIFIER ::= {at 16}
at-mhs-initials OBJECT IDENTIFIER ::= {at 17}
at-mhs-generation-qualifier OBJECT IDENTIFIER ::= {at 18}


_______________Figure_3:__Object_Identifier_Assignment_________________




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