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Versions: 00 01 02 03 04 05 06 07 RFC 2425

Network Working Group                                        Tim Howes
Request for Comments: DRAFT                                 Mark Smith
draft-ietf-asid-mime-direct-04.txt       Netscape Communications Corp.
                                                            July, 1997


             A MIME Content-Type for Directory Information
                  <draft-ietf-asid-mime-direct-04.txt>



1.  Status of this Memo

This document is an Internet-Draft.  Internet-Drafts are  working  docu-
ments  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
and  may  be  updated,  replaced, or obsoleted by other documents at any
time.  It is inappropriate to use Internet- Drafts as reference material
or to cite them other than as ``work in progress.''

To learn the current status of  any  Internet-Draft,  please  check  the
``1id-abstracts.txt''  listing  contained in the Internet- Drafts Shadow
Directories   on   ftp.is.co.za   (Africa),   nic.nordu.net    (Europe),
munnari.oz.au   (Pacific  Rim),  ds.internic.net  (US  East  Coast),  or
ftp.isi.edu (US West Coast).

2.  Abstract

This document defines a MIME Content-Type for holding directory informa-
tion.  The definition is independent of any particular directory service
or protocol.  The text/directory Content-Type is defined for  holding  a
variety  of  directory information, for example, name, or email address,
or logo. The text/directory Content-Type can also be used  as  the  root
body  part in a multipart/related Content-Type for handling more compli-
cated situations, especially those in which non-textual information that
already  has a natural MIME representation, for example, a photograph or
sound, must be represented.

The text/directory Content-Type defines a general framework  and  format
for  holding  directory  information  in  a  simple  "type: value" form.
Mechanisms are defined to specify alternate character  sets,  languages,
encodings  and  other  meta-information.  This document also defines the
procedure by which particular formats,  called  profiles,  for  carrying
application-specific  information  within  a text/directory Content-Type
may be defined and registered, and the  conventions  such  formats  must



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follow. It is expected that other documents will be produced that define
such formats for various applications (e.g., white pages).

3.  Need for a MIME Directory Type

For purposes of this document, a directory is a special-purpose database
that  contains typed information. A directory usually supports both read
and search of the information it contains, and may support  modification
of  the  information as well.  Directory information is usually accessed
far more often than it is updated.  Directories may be local  or  global
in  scope.  They may be distributed or centralized. The information they
contain may be replicated, with weak or strong consistency requirements.

There are several situations in which users of Internet mail may wish to
exchange  directory  information: the email analogy of a "business card"
exchange; the conveyance of directory information to a user having  only
email access to the Internet; the provision of machine-parseable address
information when purchasing goods or services over the Internet; etc. As
MIME  [RFC-2045,RFC-2046]  is used increasingly by other protocols, most
notably HTTP, it may also be useful for these protocols to  be  able  to
carry  directory information in MIME format. Such a format, for example,
could be used to represent URC (uniform resource characteristics) infor-
mation  about  resources on the World Wide Web, or to provide a rudimen-
tary directory service over HTTP.

4.  Overview

The scheme defined here for representing directory information in a MIME
Content-Type  has  two  parts. First, the text/directory Content-Type is
defined for use in holding directory information within  a  single  body
part,  for  example name, title, or email address. In its simplest form,
the format uses a "type: value" approach, which should be  easily  pars-
able  by existing MIME implementations and understandable by users. More
complicated situations can be represented also.  This  document  defines
the  general  form  the information in the Content-Type should have, and
the procedure by which specific types and values (properties)  for  par-
ticular  applications may be defined. The framework is general enough to
handle information from any number of end directory services,  including
LDAP [RFC-1777, RFC-1778], WHOIS++ [RFC-1835], and X.500 [X500].

Directory entries can include far more than  just  textual  information.
Some such information (e.g., an image or sound) overlaps with predefined
MIME Content-Types. In these cases it may be desirable  to  include  the
information  in its well-known MIME format. This situation is handled by
using a multipart/related Content-Type as  defined  in  [RFC-1872].  The
root component of this type is a text/directory body part specifying any
in-line information, and for information  contained  in  other  Content-
Types, the Content-IDs (in URI form) of those types.



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In some applications, it may be useful to include a pointer (e.g, a URI)
to  some directory information rather than the information itself.  This
document defines a general mechanism for accomplishing this.

5.  The text/directory Content-Type

The text/directory Content-Type is used to hold basic directory informa-
tion,  URIs  referencing  other  information,  including other MIME body
parts holding supplementary or non-textual directory  information,  such
as  an  image  or  sound. It is defined as follows, using the MIME media
type registration template from [RFC-2048].

To: ietf-types@uninett.no
Subject: Registration of MIME media type text/directory

5.1.  MIME media type name

MIME media type name: text

5.2.  MIME subtype name

MIME subtype name: directory

5.3.  Required parameters

Required parameters: charset

The "charset" parameter is as  defined  in  [RFC-2046]  for  other  body
parts.  It is used to identify the default character set used within the
body part.

5.4.  Optional parameters

Optional parameters: profile

The "profile" parameter is used to convey the type(s) of entity(ies)  to
which  the directory information pertains and the likely set of informa-
tion associated with the entity(ies). It is intended only as a guide  to
applications  interpreting  the  information  contained  within the body
part. It SHOULD NOT be used to exclude or require particular  pieces  of
information  unless  a  profile  definition  specifically calls for this
behavior. Unless specifically forbidden by a particular profile  defini-
tion,    a   text/directory   content   type   may   contain   arbitrary
attribute/value pairs.

The value of the "profile" parameter  is  defined  as  follows.  Profile
names  are case insensitive (i.e., the profile name "Person" is the same
as "PERSON" and "person" and "peRsOn").



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      profile := x-token / iana-token

      x-token := <The two characters "X-" or "x-" followed,
                  with no intervening white space, by any atom,
                  where atom is from Section 3.3 of RFC 822>

      iana-token := <a publicly-defined extension token, registered
                     with IANA, as specified in Section 9 of this
                     document>


5.5.  Encoding considerations

The default encoding is 8bit. Otherwise, as specified  by  the  Content-
Transfer-Encoding  header  field.  Note that each value may also have an
inline encoding associated with it. This encoding is independent of  the
encoding  for  the body part as a whole. When encoding, inline per-value
encodings are performed first, then Content-Transfer-Encoding is applied
to  the  entire  body part. When decoding, the Content-Transfer-Encoding
for the entire body part is decoded, then any  value-specific  encodings
are decoded.

5.6.  Security considerations

Directory information may be public or it may be  protected  from  unau-
thorized  access by the directory service in which it resides.  Once the
information leaves its native service, there can be  no  guarantee  that
the  same  care  will be taken by all services handling the information.
Furthermore, this specification defines no access control  mechanism  by
which  information may be protected, or by which access control informa-
tion may  be  conveyed.  Note  that  the  integrity  and  privacy  of  a
text/directory  body  part  may  be  protected by enclosing it within an
appropriate MIME-based security mechanism.

5.7.  Interoperability considerations

In order to make sense of directory information, applications must share
a  common understanding of the types of information contained within the
Content-Type (the directory schema).  This  schema  information  is  not
defined  in  this  document,  but  rather  in companion documents (e.g.,
[MIME-VCARD]) that follow the requirements specified in  this  document,
or in bilateral agreements between communicating parties.

5.8.  Published specification

The text/directory Content-Type contains  directory  information,  typi-
cally pertaining to a single directory entity or group of entities.  The
content consists of one or more lines in the format given below.



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5.8.1.  Line delimiting and folding

Individual lines within the MIME text/directory Content  Type  body  are
delimited  by  the [RFC-822] line break, which is a CRLF sequence (ASCII
decimal 13, followed by ASCII decimal 10). Long logical  lines  of  text
can be split into a multiple-physical-line representation using the fol-
lowing folding technique.

A logical line may be continued on the next physical line at  any  point
by inserting a CRLF immediately followed by a single white space charac-
ter (space, ASCII decimal 32, or horizontal tab, ASCII decimal  9).  Any
sequence  of CRLF followed immediately by a single white space character
is ignored (removed) when processing the content type.  For example  the
line:

DESCRIPTION:This is a long description that exists on a long line.

Can be represented as:

DESCRIPTION:This is a long description
 that exists on a long line.

The process of moving from this folded multiple-line representation of a
type  definition  to its single line representation is called unfolding.
Unfolding is accomplished by regarding CRLF immediately  followed  by  a
white  space  character as equivalent to no characters at all (i.e., the
CRLF and single white space character are removed).

A formatted text line break in an attribute value should also be  speci-
fied by a (RFC 822) line break, which is a CRLF sequence. However, since
the CRLF sequence is used to  delimit  a  content-type  line,  attribute
values with formatted line breaks (i.e., multiple lines) must be encoded
using an alternate encoding of either  Quoted-Printable  or  Base64,  as
defined in [RFC 2046].

For example, in the Quoted-Printable encoding the multiple lines of for-
matted  text  are separated with a Quoted-Printable CRLF sequence of =0D
followed by =0A followed by a Quoted-Printable soft line break  sequence
of  =.  Quoted-Printable lines of text must also be limited to less than
76 characters. The 76 characters does not include  the  CRLF  [RFC  822]
line break sequence. For example a multiple line DESCRIPTION value of:

Mythical Manager
Hyjinx Software Division
BabsCo, Inc.

Would be represented in a Quoted-Printable encoding as:




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DESCRIPTION; encoding=QUOTED-PRINTABLE:Mythical Manager=0D=0A=
Hyjinx Software Division=0D=0A=
BabsCo, Inc.

5.8.2.  BNF content-type definition

Using the notation of RFC 822, the syntax for this content is:

      contentline := [group.]type [";" parameterlist] ":" valuespec

      group := atom     ; as defined in Section 3.3 of RFC 822

      type := x-name
            / iana-type

      x-name := <the two characters "X-" or "x-" followed, with no
                 intervening white space, by any atom>

      iana-type := <a publicly-defined extension token, registered
                    with IANA, as specified in Section 11 of this
                    document>

      parameterlist := parameter / parameterlist ";" parameter

      parameter := encodingparm
                 / valuetypeparm
                 / languageparm
                 / contextparm
                 / [parmtype "="] parmvalues

      encodingparm := "encoding" "=" encodingtype

      encodingtype := "base64"            ; from Section 6.8 of RFC 2045
                    / "quoted-printable"  ; from Section 6.7 of RFC 2045
                    / "8bit"
                    / "7bit"

      valuetypeparm := "value" "=" valuetype

      valuetype := "uri"                  ; generic uri from RFC 1738
                 / "text"
                 / "date"
                 / "time"
                 / "date-time"            ; date time
                 / "integer"
                 / "boolean"
                 / "float"
                 / x-name



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                 / iana-valuetype

      iana-valuetype : = <a publicly-defined extension token, registered
                          with IANA, as defined in Section 15 of this
                          document>

      languageparm := "language" "=" language ; as defined in RFC 1766

      contextparm := "context" "=" context

      context := iana-token ; a token registered with IANA
               / x-name

      parmtype := x-name
                / iana-parmtype

      iana-parmtype := <a publicly-defined extension token, registered
                        with IANA, as defined in Section 12 of this
                        document>

      parmvalues := parmvalue
                  / parmvalues "," parmvalue

      parmvalue := x-name
                 / iana-parmvalue

      iana-parmvalue := <a publicly-defined extension token, registered
                         with IANA, as defined in Section 13 of this
                         document>

      valuespec := *text ; Characters whose syntax depends on type and the
                         ; the encoding parameter. If the value contains
                         ; a CRLF sequence (ASCII 10 followed by 13), it must
                         ; be encoded using either base64 or quoted-printable.
                 / date-spec
                 / time-spec
                 / date-time-spec
                 / boolean
                 / integer
                 / float
                 / iana-valuespec

      date-spec := date *[ "," date ]         ; date as defined in [DATETIME]

      time-spec := time *[ "," time ]         ; time as defined in [DATETIME]

      date-timed-spec := date time            ; as above




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      boolean := "TRUE" / "FALSE"

      integer := [ sign ] 1*DIGIT *[ "," integer ]    ; DIGIT as defined in RFC 822

      float := [sign] 1*DIGIT ["." *DIGIT] *("," float)

      sign := "+" / "-"

      iana-valuespec := <a publicly-defined valuetype format, registered
                         with IANA, as defined in section 15 of this
                         document>

To the left of the beginning of "value", white space characters  (namely
HTABs  and SPACEs, ASCII 9 and 32) may freely surround any symbol.  Note
that this means that if a "value" begins with white space,  it  must  be
encoded using either the base64 or quoted-printable methods.

A line that begins with a white space character is a continuation of the
previous  line,  as described above. The white space character and line-
ending CRLF should be discarded when reconstructing the  original  line.
Note  that  this  line-folding convention differs from that found in RFC
822, in that the sequence <CRLF><whitespacecharacter> found anywhere  in
the content indicates a continued line and should be removed.

Since the CRLF sequence is used to separate  lines  within  the  content
type,  if  this  sequence  appears in a value, the value must be encoded
using either base64 or quoted-printable.

The meanings of the various type names and the format of the correspond-
ing  values  must be defined as specified in Section 11.  Specifications
may impose ordering on the type constructs within a  body  part,  though
none  is required by default. The various x-name constructs are used for
bilaterally-agreed  upon  type  names,  parameter  names  and  parameter
values.

Type names, parameter names, and parameter values (i.e.,  everything  to
the  left  of the ":") are case insensitive (e.g., the type name "cn" is
the same as "CN" and "Cn").

The group construct is used to group related attributes  together.   The
group  name  is  a  syntactic  convention used to indicate that all type
names prefaced with the same group name should be grouped together  when
displayed  by an application. It has no other significance.  Implementa-
tions that do not understand or support grouping may  simply  strip  off
any text before a "." and present the types and values as normal.

Each attribute defined in the  text/directory  body  may  have  multiple
values,  if  allowed  in  the  definition  of  the  profile in which the



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attribute is used. The general rule for encoding multi-valued  items  is
to  simply  create a new content line for each value (including the type
name).  However, it should be noted that some value  types  may  support
encoding  multiple  values  in  a  single  content  line, for example by
separating the values  with  a  comma  ","  or  other  delimiter.   This
approach  has  been taken for several of the content types defined above
(date, time, integer, float), for space-saving reasons.

The "language" type parameter should be used to identify data in  alter-
nate  languages.  There  is  no concept of "default" language, except as
specified by any "Content-Language" MIME header parameter  that  may  be
present. The value of the "language" type parameter is a language tag as
defined in Section 2 of [RFC-1766].

The "context" type parameter should be used to identify a context (e.g.,
a  protocol)  used in interpreting the value. This is used, for example,
in the "name" type, defined below.

The "encoding" type parameter should be used  to  specify  an  alternate
encoding  for  a  value. If the value contains a CRLF sequence (ASCII 10
followed by 13), it must be encoded using either  "base64"  or  "quoted-
printable",  since  CRLF  is  used to separate lines in the content-type
itself. These encodings can also be useful for binary  values  that  are
mixed  with  other  text  information in the body part (e.g., a certifi-
cate). Using a per-value "base64" or "quoted-printable" encoding in this
case leaves the other information in a more readable form.

The Content-Transfer-Encoding header field is used to specify the encod-
ing  used for the body part as a whole. The "encoding" type parameter is
used to specify an encoding for a particular  value  (e.g.,  a  certifi-
cate).  In this case, the Content-Transfer-Encoding header might specify
"8bit", while the one certificate value might  specify  an  encoding  of
base64 via an "encoding=base64" type parameter.

Each type has associated with it a default encoding, which shall be used
in  the absence of an overriding "encoding" type parameter. This default
encoding is given in the type definition, as defined in  Section  11  of
this document.

The "value" parameter is optional, and may be used to identify the value
type  (data  type) and format of the value.  The use of these predefined
formats is encouraged even if the value parameter is not explicity used.
By  defining  a  standard set of value types and their formats, existing
parsing and processing code may be leveraged.

Including the value type explicitly as part of each property provides an
extra  hint to keep parsing simple and support more generalized applica-
tions.  For  example  a  search  engine  would  not  have  to  know  the



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particular  value  types for all of the items for which it is searching.
Because the value type is explicit in the definition, the search  engine
could look for dates in any item type and provide good results.

5.8.3.  Predefined value formats

Some specific notes on the value types and formats:

"text": The "text" value type should be used  to  identify  values  that
contain human-readable text. The character set and language in which the
text is represented is controlled by the charset content-header and  the
language type parameters and content-header.

"uri":  The "uri" value type should be used to identify values that  are
referenced  by  a  URI  (including a Content-ID URI), instead of encoded
in-line. These value references might be used if  the   value   is   too
large,   unavailable,  or otherwise undesirable to include directly. The
format for the URI is as defined in RFC 1738.

"date", "time", and "date-time":  Each of these value types is based  on
the  definitions in [DATETIME], which defines an Internet profile of the
ISO 8601 standard. Profiles may place further restrictions on "date" and
"time"  values  than are found in [DATETIME]. Multiple "date" and "time"
values may be specified using the comma-separated notation.

    Examples for "date":
                1985-04-12
                1996-08-05, 1996-11-11
                19850412

    Examples for "time":
                10:22:00
                102200
                10:22:00.33
                10:22:00.33Z
                10:22:33, 11:22:00
                10:22:00-08:00

    Examples for "date-time":
                1996-10-22T14:00:00Z
                1996-08-11T12:34:56Z
                19960811T123456Z
                1996-10-22T14:00:00Z, 1996-08-11T12:34:56Z

"boolean":  The "boolean" value type is used to express  boolen  values.
These values are case insensitive.

    Examples: TRUE



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              false
              true

"integer":  The "integer" value type is used to  express  32-bit  signed
integers in decimal format.  The valid range for "int" is -2147483648 to
2147483647.  If sign is not specified, the  value  is  assumed  positive
"+".  Multiple  "integer"  values  may  be  specified  using  the comma-
separated notation.

    Examples: 1234567890
              -1234556790
              +1234556790, 432109876

"float":  The "float" value type is used to express  real  numbers.   If
sign  is  not  specified,  the  value  is assumed positive "+". Multiple
"float" values may be specified using the comma-separated notation.

    Examples: 20.30
              1000000.0000001
              1.333, 3.14


5.9.  Applications which use this media type

Applications which use this media type: Various

5.10.  Additional information

Additional information: None

5.11.  Person & email address to contact for further information

   Tim Howes
   Netscape Communications Corp.
   501 East Middlefield Rd.
   Mountain View, CA 94041
   USA
   howes@netscape.com
   +1 415 937 3419

5.12.  Intended usage

Intended usage: COMMON

5.13.  Author/Change controller

   Tim Howes
   Netscape Communications Corp.



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   501 East Middlefield Rd.
   Mountain View, CA 94041
   USA
   howes@netscape.com
   +1 415 937 3419

   Mark Smith
   Netscape Communications Corp.
   501 East Middlefield Rd.
   Mountain View, CA 94041
   USA
   mcs@netscape.com
   +1 415 937 3477

6.  Predefined Types

The following types are generally useful regardless of the profile being
carried, and are defined below using the text/directory MIME type regis-
tration template defined in Section 11.1 of this document.  These  types
may  be included in any profile, unless explicitly forbidden in the pro-
file definition.

6.1.  SOURCE Type Definition

   To: ietf-mime-direct@imc.org
   Subject: Registration of text/directory MIME type SOURCE

   Type name: SOURCE

   Type purpose: To identify the source of  directory  information  con-
   tained in the content type.

   Type encoding: 8bit

   Type valuetype: text containing a URI.

   Type special notes:  The SOURCE type is used to provide the means  by
   which applications knowledgable in the given directory service proto-
   col may obtain additional or more  up-to-date  information  from  the
   directory  service.  It  contains  a  URI  as  defined  in [RFC-1738]
   referencing the directory entity or entities to which the information
   pertains.  When directory information is available from more than one
   source, the sending entity may pick what it considers to be the  best
   source, or multiple SOURCE types may be included.

   Type example:
           SOURCE: ldap://ldap.host/cn=Babs%20Jensen,%20o=Babsco,%20c=US




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6.2.  NAME Type Definition

   To: ietf-mime-direct@imc.org
   Subject: Registration of text/directory MIME type NAME

   Type name: NAME

   Type purpose: To identify  the  displayable  name  of  the  directory
   entity to which information in the content type pertains.

   Type encoding: 8bit

   Type valuetype: text

   Type special notes:  The NAME type is used to  convey  the  directory
   name  of  the entity to which the directory information pertains. Its
   value depends on the setting of the "CONTEXT" type  parameter,  which
   indicates  the  directory service protocol context in which the value
   of the NAME parameter should be interpreted. Note that this value  is
   protocol-specific  and is intended for applications knowledgable in a
   particular directory service protocol.

   Type example:
           NAME;CONTEXT=LDAP: cn=Babs Jensen, o=Babsco, c=US

6.3.  PROFILE Type Definition

   To: ietf-mime-direct@imc.org
   Subject: Registration of text/directory MIME type PROFILE

   Type name: PROFILE

   Type purpose: To identify the  type  of  directory  entity  to  which
   information in the content type pertains.

   Type encoding: 8bit

   Type valuetype:  text,  containing  a  profile  name,  registered  as
   described in Section 9 of this document or bilaterally-agreed upon as
   described in Section 5.

   Type special notes:  The PROFILE type is used to convey the  type  of
   the entity to which the directory information in the rest of the body
   part pertains. It should be the same as the "profile" header  parame-
   ter, if present.

   Type example:
           PROFILE: person



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6.4.  BEGIN Type Definition

   To: ietf-mime-direct@imc.org
   Subject: Registration of text/directory MIME type BEGIN

   Type name: BEGIN

   Type purpose: To delimit the beginning of a syntactic entity within a
   text/directory content-type.

   Type encoding: 8bit

   Type valuetype:  text,  containing  a  profile  name,  registered  as
   described in Section 9 of this document or bilaterally-agreed upon as
   described in Section 5.

   Type special notes:  The BEGIN type is used in conjunction  with  the
   END  type  to delimit a profile containing a related set of directory
   content within an text/directory content-type. This construct may  be
   used  instead of or in addition to wrapping separate sets of informa-
   tion inside additional MIME headers. It is provided for  applications
   that wish to define content that may contain multiple entities within
   the same text/directory content-type or to define content that may be
   identifiable outside of a MIME environment.

   Type example:
           BEGIN: vcard

6.5.  END Type Definition

   To: ietf-mime-direct@imc.org
   Subject: Registration of text/directory MIME type END

   Type name: END

   Type purpose: To identify the  type  of  directory  entity  to  which
   information in the content type pertains.

   Type encoding: 8bit

   Type valuetype:  text,  containing  a  profile  name,  registered  as
   described in Section 9 of this document or bilaterally-agreed upon as
   described in Section 5.

   Type special notes:  The END type is used  in  conjunction  with  the
   BEGIN type to delimit a profile containing a related set of directory
   content within an text/directory content-type. This construct may  be
   used  instead  of  or  in  addition  to  wrapping  separate  sets  of



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   information inside additional MIME headers. It is provided for appli-
   cations  that  wish to define content that may contain multiple enti-
   ties within the same text/directory content-type or to define content
   that may be identifiable outside of a MIME environment.

   Type example:
           END: vcard

7.  Use of the multipart/related Content-Type

The multipart/related Content-Type can be used to hold directory  infor-
mation  comprised  of  both  text  and non-text information or directory
information that already has a natural MIME  representation.   The  root
body part within the multipart/related body part is specified as defined
in [RFC-1872] by a "start" parameter, or it is the first  body  part  in
the  absence  of  such  a  parameter.  The  root  body  part must have a
Content-Type of "text/directory".  This part holds  inline  information,
optionally  defines  the  name  and source of the information, and makes
reference to subsequent body parts holding additional text  or  non-text
directory  information via their Content-ID URIs as explained in Section
5.

The body parts referred to do not have to be in  any  particular  order,
except as noted above for the root body part.

8.  Examples

The following examples are for illustrative purposes only  and  are  not
part of the definition.

8.1.  Example 1

The first example illustrates simple use of the text/directory  Content-
Type.  Note  that no "profile" parameter is given, so an application may
not know what kind of directory entity the information applies to.  Note
also  the  use of both hypothetical official and bilaterally agreed upon
types.

   From: Whomever@wherever.com
   To: Someone@somewhere.com
   Subject: whatever
   MIME-Version: 1.0
   Message-ID: <id1@host.net>
   Content-Type: text/directory
   Content-ID: <id2@host.com>

   cn: Babs Jensen
   cn: Barbara J Jensen



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   sn: Jensen
   email: babs@umich.edu
   phone: +1 313 747-4454
   x-id: 1234567890

8.2.  Example 2

The next example illustrates the use of  the  Quoted-Printable  encoding
defined  in  [RFC  2045]  to  include non-ASCII character in some of the
information returned, and the use of the optional  "name"  and  "source"
types.  It  also  illustrates the use of an "encoding" type parameter to
encode a certificate value in base64. A "vCard" profile [MIME-VCARD]  is
used for the example.

   Content-Type: text/directory;
           charset="iso-8859-1";
           profile="vCard"
   Content-ID: <id3@host.com>
   Content-Transfer-Encoding: Quoted-Printable

   begin: vcard
   source: ldap://cn=3Dbjorn%20Jensen, o=3Duniversity%20of%20Michigan, c=3DUS
   name: cn=3Dbjorn Jensen, o=3Duniversity of Michigan, c=3DUS
   fn: Bj=F8rn Jensen
   n: Jensen;Bj=F8rn
   email;type=3Dinternet: bjorn@umich.edu
   tel;type=3Dwork,voice,msg:+1 313 747-4454
   key;type=3Dx509;encoding=3Dbase64: dGhpcyBjb3VsZCBiZSAKbXkgY2VydGlmaWNhdGUK
   end: vcard

8.3.  Example 3

The next example illustrates the use of  multi-valued  type  parameters,
the  "language"  type  parameter,  the  "value"  type  parameter, inline
quoted-printable encoding to represent iso-8859-1  characters  and  fold
long lines, and attribute grouping.

   Content-Type: text/directory; profile="person"; charset=iso-8859-1
   Content-ID: <id3@host.com>

   source: ldap://cn=Meister%20Berger,o=Universitaet%20Goerlitz,c=DE
   name: cn=Meister Berger, o=Universitaet Goerlitz, c=DE
   cn: Meister Berger
   cn: Berger Meister
   sn: Berger
   age;value=integer: 33
   o;encoding=quoted-printable: Universit=E6t G=F6rlitz
   title: Mayor



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   title;language=de;value=text: Burgermeister
   description;encoding=quoted-printable: The Mayor of the great city of=
    Goerlitz in the great country of Germany.
   email: mb@goerlitz.de
   home.phone;fax,voice,msg: +49 3581 123456
   home.addr;encoding=quoted-printable: Hufenshlagel 1234=0A=
    02828 Goerlitz=0A=
    Deutschland
   certificate;encoding=base64: dGhpcyBjb3VsZCBiZSAKbXkgY2VydGlma...

8.4.  Example 4

The final example illustrates the use of the multipart/related  Content-
Type  to  include  non-textual  directory data via the "uri" encoding to
refer to other body parts  within  the  same  message,  or  to  external
values.

   Content-Type: multipart/related;
           boundary=woof;
           type="text/directory";
           start="<id5@host.com>"
   Content-ID: <id4@host.com>

   --woof
   Content-Type: text/directory; charset="iso-8859-1"
   Content-ID: <id5@host.com>
   Content-Transfer-Encoding: Quoted-Printable

   source: ldap://cn=3DBjorn%20Jensen,o=3DUniversity%20of%20Michigan,c=3DUS
   cn: Bj=F8rn Jensen
   sn: Jensen
   email: bjorn@umich.edu
   image;encoding=3Duri: cid:id6@host.com
   image;encoding=3Duri;format=3Djpeg: ftp://some.host/some/path.jpg
   sound;encoding=3Duri: cid:id7@host.com
   phone: +1 313 747-4454

   --woof
   Content-Type: image/jpeg
   Content-ID: <id6@host.com>

   <...image data...>

   --woof
   Content-Type: message/external-body;
           name="myvoice.au";
           site="myhost.com";
           access-type=ANON-FTP;



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           directory="pub/myname";
           mode="image"

   Content-Type: audio/basic
   Content-ID: <id7@host.com>

   --woof--

9.  Registration of new profiles

This section defines procedures by which  new  profiles  are  registered
with  the  IANA  and made available to the Internet community. Note that
non-IANA profiles may be used by bilateral agreement, provided the asso-
ciated profile names follow the "X-" convention defined above.

The procedures defined here are designed to  allow  public  comment  and
review  of  new  profiles,  while  posing only a small impediment to the
definition of new profiles.

Registration of a new profile is accomplished by the following steps.

9.1.  Define the profile

A profile is defined by completing the following template.

   To: ietf-mime-direct@imc.org
   Subject: Registration of text/directory MIME profile XXX

   Profile name:

   Profile purpose:

   Profile types:

   Profile special notes (optional):

   Intended usage: (one of COMMON, LIMITED USE or OBSOLETE)

The explanation of what goes in each field in the template follows.

Profile name: The  name  of  the  profile  as  it  will  appear  in  the
text/directory  MIME  Content-Type  "profile"  header  parameter, or the
predefined "profile" type name.

Profile purpose: The purpose of the profile (e.g., to represent informa-
tion  about  people,  printers, documents, etc.). Give a short but clear
description.




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Profile types: The list of types associated with the profile.  This list
of  types is to be expected but not required in the profile, unless oth-
erwise noted in the profile definition.  Other types  not  mentioned  in
the  profile  definition  may  also be present.  Note that any new types
referenced by the profile must be defined  separately  as  described  in
Section 10.

Profile special notes: Any special notes about the profile, how it is to
be used, etc. This section of the template may also be used to define an
ordering on the types that appear in the Content-Type, if such an order-
ing is required.

9.2.  Post the profile definition

The profile description must be posted to  the  new  profile  discussion
list, ietf-mime-direct@imc.org

9.3.  Allow a comment period

Discussion on the new profile must be allowed to take place on the  list
for  a  minimum  of  two weeks. Consensus must be reached on the profile
before proceeding to step 4.

9.4.  Submit the profile for approval

Once the two-week comment period has elapsed, and the proposer  is  con-
vinced  consensus  has  been  reached  on  the profile, the registration
application should be submitted to the Profile  Reviewer  for  approval.
The  Profile Reviewer is appointed to the Application Area Directors and
may either accept or reject the profile registration. An accepted regis-
tration  should  be  passed  on  by the Profile Reviewer to the IANA for
inclusion in the official IANA profile registry. The registration may be
rejected  for  any  of  the  following  reasons. 1) Insufficient comment
period; 2) Consensus not reached; 3) Technical  deficiencies  raised  on
the  list  or  elsewhere have not been addressed. The Profile Reviewer's
decision to reject a profile may be appealed  by  the  proposer  to  the
IESG,  or the objections raised can be addressed by the proposer and the
profile resubmitted.

10.  Profile Change Control

Existing profiles may be changed using the same process  by  which  they
were registered.

     Define the change

     Post the change




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     Allow a comment period

     Submit the changed profile for approval

Note that the original author or any other interested party may  propose
a  change  to  an existing profile, but that such changes should only be
proposed when there are serious omissions or  errors  in  the  published
specification.  The Profile Reviewer may object to a change if it is not
backwards compatible, but is not required to do so.

Profile definitions can never be deleted from  the  IANA  registry,  but
profiles  which  are  no  longer  believed  to be useful can be declared
OBSOLETE by a change to their "intended use" field.

11.  Registration of new types

This section defines procedures by which new types are  registered  with
the  IANA.  Note that non-IANA types may be used by bilateral agreement,
provided the associated types names follow the "X-"  convention  defined
above.

The procedures defined here are designed to  allow  public  comment  and
review of new types, while posing only a small impediment to the defini-
tion of new types.

Registration of a new type is accomplished by the following steps.

11.1.  Define the type

A type is defined by completing the following template.

      To: ietf-mime-direct@imc.org
      Subject: Registration of text/directory MIME type XXX

      Type name:

      Type purpose:

      Type encoding:

      Type valuetype:

      Type special notes (optional):

      Intended usage: (one of COMMON, LIMITED USE or OBSOLETE)

The meaning of each field in the template is as follows.




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Type name: The name of the type, as it will appear in  the  body  of  an
text/directory  MIME  Content-Type "type: value" line to the left of the
colon ":".

Type purpose: The purpose of the type (e.g., to represent a name, postal
address, IP address, etc.). Give a short but clear description.

Type encoding: The default encoding a value of the type must have in the
body of a text/directory MIME Content-Type.

Type valuetype: The format a value of the type must have in the body  of
a text/directory MIME Content-Type. This description must be precise and
must not violate the general encoding rules defined in section 5 of this
document.

Type special notes: Any special notes about the type, how it  is  to  be
used, etc.

11.2.  Post the type definition

The type description must be posted to the  new  type  discussion  list,
ietf-mime-direct@imc.org

11.3.  Allow a comment period

Discussion on the new type must be allowed to take place on the list for
a  minimum  of  two  weeks. Consensus must be reached on the type before
proceeding to step 4.

11.4.  Submit the type for approval

Once the two-week comment period has elapsed, and the proposer  is  con-
vinced consensus has been reached on the type, the registration applica-
tion should be submitted to the Profile Reviewer for approval.  The Pro-
file  Reviewer  is  appointed  to the Application Area Directors and may
either accept or reject the type registration. An accepted  registration
should be passed on by the Profile Reviewer to the IANA for inclusion in
the official IANA profile registry. The registration may be rejected for
any  of  the  following reasons. 1) Insufficient comment period; 2) Con-
sensus not reached; 3) Technical deficiencies  raised  on  the  list  or
elsewhere  have  not  been addressed. The Profile Reviewer's decision to
reject a type may be appealed by the proposer to the IESG, or the objec-
tions raised can be addressed by the proposer and the type resubmitted.

12.  Type Change Control

Existing types may be changed using the same process by which they  were
registered.



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     Define the change

     Post the change

     Allow a comment period

     Submit the type for approval

Note that the original author or any other interested party may  propose
a  change to an existing type, but that such changes should only be pro-
posed when there are  serious  omissions  or  errors  in  the  published
specification.  The Profile Reviewer may object to a change if it is not
backwards compatible, but is not required to do so.

Type definitions can never be deleted from the IANA registry, but  types
which  are  nolonger believed to be useful can be declared OBSOLETE by a
change to their "intended use" field.

13.  Registration of new parameters

This section defines procedures by which new parameters  are  registered
with  the  IANA  and made available to the Internet community. Note that
non-IANA parameters may be used by  bilateral  agreement,  provided  the
associated parameters names follow the "X-" convention defined above.

The procedures defined here are designed to  allow  public  comment  and
review  of  new  parameters, while posing only a small impediment to the
definition of new parameters.

Registration of a new parameter is accomplished by the following steps.

13.1.  Define the parameter

A parameter is defined by completing the following template.

   To: ietf-mime-direct@imc.org
   Subject: Registration of text/directory MIME type parameter XXX

   Parameter name:

   Parameter purpose:

   Parameter values:

   Parameter special notes (optional):

   Intended usage: (one of COMMON, LIMITED USE or OBSOLETE)




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The explanation of what goes in each field in the template follows.

Parameter name: The name of the parameter  as  it  will  appear  in  the
text/directory MIME Content-Type.

Parameter purpose: The purpose of the parameter (e.g., to represent  the
format  of  an  image,  type  of a phone number, etc.). Give a short but
clear description. If defining a general  paramemter  like  "format"  or
"type" keep in mind that other applications may wish to extend its use.

Parameter values: The list or description of values associated with  the
parameter.

Parameter special notes: Any special notes about the parameter,  how  it
is to be used, etc.

13.2.  Post the parameter definition

The parameter description must be posted to the new parameter discussion
list, ietf-mime-direct@imc.org

13.3.  Allow a comment period

Discussion on the new parameter must be allowed to  take  place  on  the
list for a minimum of two weeks. Consensus must be reached on the param-
eter before proceeding to step 4.

13.4.  Submit the parameter for approval

Once the two-week comment period has elapsed, and the proposer  is  con-
vinced  consensus  has  been  reached on the parameter, the registration
application should be submitted to the Profile  Reviewer  for  approval.
The  Profile Reviewer is appointed to the Application Area Directors and
may either accept or reject  the  parameter  registration.  An  accepted
registration should be passed on by the Profile Reviewer to the IANA for
inclusion in the official IANA parameter registry. The registration  may
be  rejected  for  any of the following reasons. 1) Insufficient comment
period; 2) Consensus not reached; 3) Technical  deficiencies  raised  on
the  list  or  elsewhere have not been addressed. The Profile Reviewer's
decision to reject a profile may be appealed  by  the  proposer  to  the
IESG,  or the objections raised can be addressed by the proposer and the
parameter registration resubmitted.

14.  Parameter Change Control

Existing parameters may be changed using the same process by which  they
were registered.




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     Define the change

     Post the change

     Allow a comment period

     Submit the parameter for approval

Note that the original author or any other interested party may  propose
a  change to an existing parameter, but that such changes should only be
proposed when there are serious omissions or  errors  in  the  published
specification.  The Profile Reviewer may object to a change if it is not
backwards compatible, but is not required to do so.

Parameter definitions can never be deleted from the IANA  registry,  but
parameters  which  are  nolonger  believed  to be useful can be declared
OBSOLETE by a change to their "intended use" field.

15.  Registration of new value types

This section defines procedures by which new value types are  registered
with  the  IANA  and made available to the Internet community. Note that
non-IANA value types may be used by  bilateral agreement,  provided  the
associated value types names follow the "X-" convention defined above.

The procedures defined here are designed to  allow  public  comment  and
review  of  new value types, while posing only a small impediment to the
definition of new value types.

Registration of a new value  types  is  accomplished  by  the  following
steps.


15.1.  Define the value type

A value type is defined by completing the following template.

      To: ietf-mime-direct@imc.org
      Subject: Registration of text/directory MIME value type XXX

      value type name:

      value type purpose:

      value type format:

      value type special notes (optional):




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      Intended usage: (one of COMMON, LIMITED USE or OBSOLETE)

The explanation of what goes in each field in the template follows.

value type name: The name of the value type as  it  will  appear  in the
text/directory MIME Content-Type.

value type purpose: The purpose of the value  type.  Give  a  short  but
clear description.

value type format: The definition of the format for the  value,  usually
using BNF grammar.

value type special notes: Any special notes about the value  type,   how
it is to be used, etc.


15.2.  Post the value type definition

The value type description must be posted to the new value type  discus-
sion list, ietf-mime-direct@imc.org


15.3.  Allow a comment period

Discussion on the new value type must be allowed to  take  place  on the
list  for  a  minimum  of  two  weeks.  Consensus must be reached before
proceeding to step 4.


15.4.  Submit the value type for approval

Once the two-week comment period has elapsed, and the proposer  is  con-
vinced   consensus   has  been  reached on the value type, the registra-
tion application should  be  submitted  to  the  Profile   Reviewer  for
approval.   The   Profile  Reviewer is appointed to the Application Area
Directors and may either accept or reject  the  value type registration.
An  accepted registration should be passed on by the Profile Reviewer to
the IANA for inclusion in the official IANA  value  type  registry.  The
registration  may  be   rejected   for  any of the following reasons. 1)
Insufficient comment period; 2)  Consensus  not  reached;  3)  Technical
deficiencies    raised   on  the   list   or  elsewhere  have  not  been
addressed. The Profile Reviewer's decision to reject a  profile  may  be
appealed  by  the  proposer  to  the IESG,  or the objections raised can
be addressed by the proposer and the value type  registration  resubmit-
ted.





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16.  Security Considerations

Internet mail is subject to many well known security attacks,  including
monitoring,  replay,  and forgery. Care should be taken by any directory
service in allowing information  to  leave  the  scope  of  the  service
itself, where any access controls can no longer be guaranteed.  Applica-
tions should also take care  to  display  directory  data  in  a  "safe"
environment (e.g., PostScript-valued types).

17.  Acknowledgements

The registration procedures defined here were  shamelessly  lifted  from
the MIME registration RFC.

The many valuable comments contributed by members of the IETF ASID work-
ing  group  are gratefully acknowledged, as are the contributions of the
Versit Consortium..

18.  Bibliography

[RFC-1777] Yeong, W.,  Howes,  T.,  Kille,  S.,  "Lightweight  Directory
           Access Protocol", Request for Comment (RFC) 1777, March 1995.

[RFC-1778] Howes, T., Kille, S., Yeong, W., Robbins, C.J.,  "The  String
           Representation  of  Standard Attribute Syntaxes", Request for
           Comment (RFC) 1778, March 1995.

[RFC-822]  Crocker, D., "Standard for the Format of ARPA  Internet  Text
           Messages", STD 11, RFC 822, August 1982.

[RFC-1521] Borenstein, N., Freed, N., "Multipurpose Internet Mail Exten-
           sions  (MIME)  Part  One: Format of Internet Message Bodies",
           RFC 2045, November 1996.

[RFC-2046] Moore, K., "Multipurpose Internet Mail Extensions (MIME) Part
           Two:  Media Types", RFC 2046, November 1996.

[RFC-2048] Freed, N., Klensin, J., Postel,  J.,  "Multipurpose  Internet
           Mail  Extensions  (MIME) Part Four: Registration Procedures",
           RFC 2048, November 1996

[RFC-1766] Alvestrand, H., "Tags for the Identification  of  Languages",
           RFC 1766, March 1995.

[RFC-1872] Levinson, E., "The MIME Multipart/Related Content-type,"  RFC
           1872, December 1995.

[X500]     "Information    Processing    Systems    -    Open    Systems



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           Interconnection - The Directory: Overview of Concepts, Models
           and Services", ISO/IEC  JTC  1/SC21,  International  Standard
           9594-1, 1988.

[RFC-1835] Deutsch, P., Schoultz, R., Faltstrom, P., Weider, C., "Archi-
           tecture of the WHOIS++ service", August 1995.

[RFC-1738] Berners-Lee,  T.,  Masinter,  L.,  McCahill,   M.,   "Uniform
           Resource Locators (URL)", RFC 1738, December 1994.

[DATETIME] Newman, C., "Date and Time on the Internet",  Internet  Draft
           draft-newman-datetime-01.txt, January 1997.

[MIME-VCARD]F.  Dawson,  T.  Howes,  "VCard  MIME  Directory   Profile",
           Internet-Draft    draft-ietf-asid-mime-vcard-02.txt,   March,
           1997.

[VCARD]    Versit Consortium, "vCard - The  Electronic  Business  Card",
           Version  2.1, http://www.imc.com/pdi/vcard-21.txt, September,
           1996.

19.  Author's Address

   Tim Howes
   Netscape Communications Corp.
   501 East Middlefield Rd.
   Mountain View, CA 94041
   USA
   howes@netscape.com
   +1.415.937.3419

   Mark Smith
   Netscape Communications Corp.
   501 East Middlefield Rd.
   Mountain View, CA 94041
   USA
   mcs@netscape.com
   +1.415.937.3477

20.  Table of Contents


1.     Status of this Memo............................................1
2.     Abstract.......................................................1
3.     Need for a MIME Directory Type.................................2
4.     Overview.......................................................2
5.     The text/directory Content-Type................................3



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5.1.      MIME media type name........................................3
5.2.      MIME subtype name...........................................3
5.3.      Required parameters.........................................3
5.4.      Optional parameters.........................................3
5.5.      Encoding considerations.....................................4
5.6.      Security considerations.....................................4
5.7.      Interoperability considerations.............................4
5.8.      Published specification.....................................4
5.8.1.       Line delimiting and folding..............................5
5.8.2.       BNF content-type definition..............................6
5.8.3.       Predefined value formats.................................10
5.9.      Applications which use this media type......................11
5.10.     Additional information......................................11
5.11.     Person & email address to contact for further information...11
5.12.     Intended usage..............................................11
5.13.     Author/Change controller....................................11
6.     Predefined Types...............................................12
6.1.      SOURCE Type Definition......................................12
6.2.      NAME Type Definition........................................13
6.3.      PROFILE Type Definition.....................................13
6.4.      BEGIN Type Definition.......................................14
6.5.      END Type Definition.........................................14
7.     Use of the multipart/related Content-Type......................15
8.     Examples.......................................................15
8.1.      Example 1...................................................15
8.2.      Example 2...................................................16
8.3.      Example 3...................................................16
8.4.      Example 4...................................................17
9.     Registration of new profiles...................................18
9.1.      Define the profile..........................................18
9.2.      Post the profile definition.................................19
9.3.      Allow a comment period......................................19
9.4.      Submit the profile for approval.............................19
10.    Profile Change Control.........................................19
11.    Registration of new types......................................20
11.1.     Define the type.............................................20
11.2.     Post the type definition....................................21
11.3.     Allow a comment period......................................21
11.4.     Submit the type for approval................................21
12.    Type Change Control............................................21
13.    Registration of new parameters.................................22
13.1.     Define the parameter........................................22
13.2.     Post the parameter definition...............................23
13.3.     Allow a comment period......................................23
13.4.     Submit the parameter for approval...........................23
14.    Parameter Change Control.......................................23
15.    Registration of new value types................................24


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15.1.     Define the value type.......................................24
15.2.     Post the value type definition..............................25
15.3.     Allow a comment period......................................25
15.4.     Submit the value type for approval..........................25
16.    Security Considerations........................................26
17.    Acknowledgements...............................................26
18.    Bibliography...................................................26
19.    Author's Address...............................................27
20.    Table of Contents..............................................27

























































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