Internet DRAFT - draft-ietf-asid-mime-direct
draft-ietf-asid-mime-direct
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Network Working Group Tim Howes
INTERNET DRAFT Mark Smith
draft-ietf-asid-mime-direct-07.txt Netscape Communications Corp.
Frank Dawson
Lotus Development Corporation
April 20, 1998
A MIME Content-Type for Directory Information
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), ftp.ietf.org (US East Coast, or ftp.isi.edu
(US West Coast).
Distribution of this memo is unlimited.
Copyright (C) The Internet Society 1998. All Rights Reserved.
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, is to be represented.
The text/directory Content-Type defines a general framework and format
for holding directory information in a simple "type:value" form. We
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refer to "type" in this context meaning a property or attribute with
which the value is associated. Mechanisms are defined to specify alter-
nate 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 can be defined and registered, and the conventions such
formats must follow. It is expected that other documents will be pro-
duced that define such formats for various applications (e.g., white
pages).
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].
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 can support creation and
modification of the information as well. Directory information is usu-
ally accessed far more often than it is updated. Directories can be
local or global in scope. They can be distributed or centralized. The
information they contain can be replicated, with weak or strong con-
sistency requirements.
There are several situations in which users of Internet mail might 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 proto-
cols, most notably HTTP, it can also be useful for these protocols 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 parse-
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
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particular applications can be defined. The framework is general enough
to handle information from any number of end directory services, includ-
ing 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 can 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-2112]. 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 parts.
In some applications, it can 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 and 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
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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 can 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 "vCard" is the same
as "VCARD" and "vcard" and "vcArD").
profile = x-name / iana-token
x-name = "x-" 1*(ALPHA / DIGIT / "-")
; Names beginning with "x-" or "X-" are
; reserved for experimental use not intended for released
; products, or for use in bilateral agreements.
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.
5.6. Security considerations
Directory information can be public or it can 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 can be protected, or by which access control informa-
tion can be conveyed. Note that the integrity and privacy of a
text/directory body part can 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
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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.
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 anywhere
between two characters by inserting a CRLF immediately followed by a
single white space character (space, ASCII decimal 32, or horizontal
tab, ASCII decimal 9). At least one character must be present on the
folded line. 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.
It could also be represented as:
DESCRIPTION:This is a long descrip
tion that exists o
n 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 (namely HTAB ASCII decimal 9 or SPACE ASCII
decimal 32) as equivalent to no characters at all (i.e., the CRLF and
single white space character are removed).
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5.8.2. ABNF content-type definition
The following ABNF uses the notation of RFC 2234, which also defines
CRLF, WSP, DQUOTE, VCHAR, ALPHA, and DIGIT. After the unfolding of any
folded lines as described above, the syntax for a line of this content
type is as follows:
contentline = [group "."] name *(";" param) ":" value CRLF
; When parsing a content line, folded lines MUST first
; be unfolded according to the unfolding procedure
; described above.
; When generating a content line, lines longer than 75
; characters SHOULD be folded according to the folding
; procedure described above.
group = 1*(ALPHA / DIGIT / "-")
name = x-name / iana-token
iana-token = 1*(ALPHA / DIGIT / "-")
; identifier registered with IANA
x-name = "x-" 1*(ALPHA / DIGIT / "-")
; Names that begin with "x-" or "X-" are
; reserved for experimental use, not intended for released
; products, or for use in bilateral agreements.
param = param-name "=" param-value *("," param-value)
param-name = x-name / iana-token
param-value = ptext / quoted-string
ptext = *SAFE-CHAR
value = *VALUE-CHAR
/ valuespec ; valuespec defined in section 5.8.4
quoted-string = DQUOTE *QSAFE-CHAR DQUOTE
NON-ASCII = %x80-FF
; use restricted by charset parameter
; on outer MIME object (UTF-8 preferred)
QSAFE-CHAR = WSP / %x21 / %x23-7E / NON-ASCII
; Any character except CTLs, DQUOTE
SAFE-CHAR = WSP / %x21 / %x23-2B / %x2D-39 / %x3C-7E / NON-ASCII
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; Any character except CTLs, DQUOTE, ";", ":", ","
VALUE-CHAR = WSP / VCHAR / NON-ASCII
; any textual character
A line that begins with a white space character is a continuation of the
previous line, as described above. The white space character and immedi-
ately preceeding CRLF should be discarded when reconstructing the origi-
nal line. Note that this line-folding convention differs from that found
in RFC 822, in that the sequence <CRLF><WSP> found anywhere in the con-
tent indicates a continued line and should be removed.
Various type names and the format of the corresponding values are
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, or for use in
experimental settings.
Type names and parameter names are case insensitive (e.g., the type name
"fn" is the same as "FN" and "Fn"). Parameter values MAY be case sensi-
tive or case insensitive, depending on their definition.
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 "." to the left of the type name 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 attri-
bute 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 support encod-
ing multiple values in a single content line by separating the values
with a comma ",". This approach has been taken for several of the con-
tent types defined below (date, time, integer, float), for space-saving
reasons.
5.8.3. Pre-defined Parameters
The following parameters and value types are defined for general use.
predefined-param = encodingparm
/ valuetypeparm
/ languageparm
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/ contextparm
encodingparm = "encoding" "=" encodingtype
encodingtype = "b" ; from RFC 2047
/ iana-token ; registered as described in
; section 15 of this document
valuetypeparm = "value" "=" valuetype
valuetype = "uri" ; genericurl from secion 5 of RFC 1738
/ "text"
/ "date"
/ "time"
/ "date-time" ; date time
/ "integer"
/ "boolean"
/ "float"
/ x-name
/ iana-token ; registered as described in
; section 15 of this document
languageparm = "language" "=" Language-Tag
; Language-Tag is defined in section 2 of RFC 1766
contextparm = "context" "=" context
context = x-name
/ iana-token
The "language" type parameter is used to identify data in multiple
languages. There is no concept of "default" language, except as speci-
fied by any "Content-Language" MIME header parameter that is present.
The value of the "language" type parameter is a language tag as defined
in Section 2 of [RFC-1766].
The "context" type parameter is used to identify a context (e.g., a pro-
tocol) used in interpreting the value. This is used, for example, in the
"source" type, defined below.
The "encoding" type parameter is used to specify an alternate encoding
for a value. If the value contains a CRLF, it must be encoded, since
CRLF is used to separate lines in the content-type itself. Currently,
only the "b" encoding is supported.
The "b" encoding can also be useful for binary values that are mixed
with other text information in the body part (e.g., a certificate).
Using a per-value "b" encoding in this case leaves the other information
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in a more readable form. The encoded base 64 value can be split across
multiple physical lines in the content type by using the line folding
technique described above.
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 "b"
via an "encoding=b" type parameter.
Each type has associated with it a default encoding, taken from the
Content-Transfer-Encoding MIME header parameter.
The "value" parameter is optional, and is 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 can 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 particu-
lar 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 results that can still be
interpreted.
5.8.4. Pre-defined Value Types
The format for values corresponding to the predefined valuetype specifi-
cations given above are defined.
valuespec = text-list
/ genericurl ; from section 5 of RFC 1738
/ date-list
/ time-list
/ date-time-list
/ boolean
/ integer-list
/ float-list
/ iana-valuespec
text-list = *TEXT-LIST-CHAR *("," *TEXT-LIST-CHAR)
TEXT-LIST-CHAR = "\\" / "\," / "\n"
/ <any VALUE-CHAR except , or \ or newline>
; Backslashes, newlines, and commas must be encoded.
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; \n or \N can be used to encode a newline.
date-list = date *("," date)
time-list = time *("," time)
date-time-list = date "T" time *("," date "T" time)
boolean = "TRUE" / "FALSE"
integer-list = integer *("," integer)
integer = [sign] 1*DIGIT
float-list = float *("," float)
float = [sign] 1*DIGIT ["." 1*DIGIT]
sign = "+" / "-"
date = date-fullyear ["-"] date-month ["-"] date-mday
date-fullyear = 4 DIGIT
date-month = 2 DIGIT ;01-12
date-mday = 2 DIGIT ;01-28, 01-29, 01-30, 01-31
;based on month/year
time = time-hour [":"] time-minute [":"] time-second [time-secfrac]
[time-zone]
time-hour = 2 DIGIT ;00-23
time-minute = 2 DIGIT ;00-59
time-second = 2 DIGIT ;00-60 (leap second)
time-secfrac = "," 1*DIGIT
time-zone = "Z" / time-numzone
time-numzome = sign time-hour [":"] time-minute
iana-valuespec = <a publicly-defined valuetype format, registered
with IANA, as defined in section 15 of this
document>
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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 parameter and content-header.
Examples for "text":
this is a text value
this is one value,this is another
this is a single value\, with a comma encoded
A formatted text line break in a text value type MUST be represented as
the character sequence backslash (ASCII decimal 92) followed by a Latin
small letter n (ASCII decimal 110) or a Latin capital letter N (ASCII
decimal 78), that is "\n" or "\N".
For example a multiple line DESCRIPTION value of:
Mythical Manager
Hyjinx Software Division
BabsCo, Inc.
could be represented as:
DESCRIPTION:Mythical Manager\nHyjinx Software Division\n
BabsCo\, Inc.\n
demonstrating the \n literal formatted line break technique, the CRLF-
followed-by-space line folding technique, and the backslash escape tech-
nique.
"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, or otherwise undesirable to include directly. The format for the
URI is as defined in RFC 1738.
Examples for "uri":
http://www.foobar.com/my/picture.jpg
ldap://ldap.foobar.com/cn=babs%20jensen
"date", "time", and "date-time": Each of these value types is based on
a subset of the definitions in ISO 8601 standard. Profiles MAY place
further restrictions on "date" and "time" values. Multiple "date" and
"time" values can be specified using the comma-separated notation,
unless restricted by a profile.
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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
false
True
"integer": The "integer" value type is used to express signed integers
in decimal format. If sign is not specified, the value is assumed posi-
tive "+". Multiple "integer" values can be specified using the comma-
separated notation, unless restricted by a profile.
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 can be specified using the comma-separated notation,
unless restricted by a profile.
Examples: 20.30
1000000.0000001
1.333,3.14
5.9. Applications which use this media type
Applications which use this media type: Various
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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.
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
Frank Dawson
Lotus Development Corporation
6544 Battleford Drive
Raleigh, NC 27613-3502
USA
frank_dawson@lotus.com
+1-919-676-9515
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
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registration template defined in Section 11.1 of this document. These
types MAY be included in any profile, unless explicitly forbidden in the
profile 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: uri
Type special notes: The SOURCE type is used to provide the means by
which applications knowledgable in the given directory service proto-
col can obtain additional or more up-to-date information from the
directory service. It contains a URI as defined in [RFC-1738] and/or
other information referencing the directory entity or entities to
which the information pertains. When directory information is avail-
able from more than one source, the sending entity can pick what it
considers to be the best source, or multiple SOURCE types can be
included. The interpretation of the value for a SOURCE type can
depend on the setting of the CONTEXT type parameter. The value of the
CONTEXT type parameter MUST be compatible with the value of the uri
prefix.
Type example:
SOURCE;CONTEXT=LDAP:ldap://ldap.host/cn=Babs%20Jensen,
%20o=Babsco,%20c=US
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
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Type special notes: The NAME type is used to convey the display name
of the entity to which the directory information pertains.
Type example:
NAME:Babs Jensen's Contact Information
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: 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:vCard
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 denote 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 properties
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within an text/directory content-type. This construct can be used
instead of or in addition to wrapping separate sets of information
inside additional MIME headers. It is provided for applications that
wish to define content that can contain multiple entities within the
same text/directory content-type or to define content that can 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 denote the end 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 END type is used in conjunction with the
BEGIN type to delimit a profile containing a related set of proper-
ties within an text/directory content-type. This construct can 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 can contain multiple entities within
the same text/directory content-type or to define content that can 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-2112] 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
and makes reference to subsequent body parts holding additional text or
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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
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 transfer
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 param-
eter to encode a certificate value in "b". 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
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begin:VCARD
source:ldap://cn=3Dbjorn%20Jensen, o=3Duniversity%20of%20Michigan, c=3DUS
name:Bjorn Jensen
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=3DB: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, folding of
long lines, the \n encoding for formatted lines, attribute grouping, and
the inline "b" encoding. A "vCard" profile [MIME-VCARD] is used for the
example.
Content-Type: text/directory; profile="vcard"; charset=iso-8859-1
Content-ID: <id3@host.com>
Content-Transfer-Encoding: Quoted-Printable
begin:vcard
source:ldap://cn=3DMeister%20Berger,o=3DUniversitaet%20Goerlitz,c=3DDE
name:Meister Berger
fn:Meister Berger
n:Berger;Meister
bday;value=3Ddate:1963-09-21
o:Universit=E6t G=F6rlitz
title:Mayor
title;language=3Dde;value=3Dtext:Burgermeister
note:The Mayor of the great city of
Goerlitz in the great country of Germany.
email;internet:mb@goerlitz.de
home.tel;type=3Dfax,voice,msg:+49 3581 123456
home.label:Hufenshlagel 1234\n
02828 Goerlitz\n
Deutschland
key;type=3DX509;encoding=3Db:MIICajCCAdOgAwIBAgICBEUwDQYJKoZIhvcNAQEEBQ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w0BAQQFAAOBgQBexv7o7mi3PLXadkmNP9LcIPmx93HGp0Kgyx1jIVMyNgsemeAwBM+M
SlhMfcpbTrONwNjZYW8vJDSoi//yrZlVt9bJbs7MNYZVsyF1unsqaln4/vy6Uawfg8V
UMk1U7jt8LYpo4YULU7UZHPYVUaSgVttImOHZIKi4hlPXBOhcUQ=3D=3D
end:vcard
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. 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.
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;value=3Duri:cid:id6@host.com
image;value=3Duri;format=3Djpeg:ftp://some.host/some/path.jpg
sound;value=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;
directory="pub/myname";
mode="image"
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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 can 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.
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
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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 can 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 by the Application Area Directors and
can either accept or reject the profile registration. An accepted regis-
tration is 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 can 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 can be changed using the same process by which they
were registered.
Define the change
Post the change
Allow a comment period
Submit the changed profile for approval
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Note that the original author or any other interested party can 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 can 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 can 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.
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 ":".
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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 by the Application Area Directors and can
either accept or reject the type registration. An accepted registration
is passed on by the Profile Reviewer to the IANA for inclusion in the
official IANA profile registry. The registration can 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
type can be appealed by the proposer to the IESG, or the objections
raised can be addressed by the proposer and the type resubmitted.
12. Type Change Control
Existing types can 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 type for approval
Note that the original author or any other interested party can 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 can 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 can 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)
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.
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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 might 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 by the Application Area Directors and
can either accept or reject the parameter registration. An accepted
registration is passed on by the Profile Reviewer to the IANA for inclu-
sion in the official IANA parameter registry. The registration can 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 can 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 can 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 parameter for approval
Note that the original author or any other interested party can 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 can 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 can 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):
Intended usage: (one of COMMON, LIMITED USE or OBSOLETE)
The explanation of what goes in each field in the template follows.
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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 ABNF 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 by the Application Area
Directors and can 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 can 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 can 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.
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
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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. Chris Newman was especially helpful in navigating the
intricacies of ABNF lore.
18. References
[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-2045] 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-2112] Levinson, E., "The MIME Multipart/Related Content-type," RFC
2112, March 1997.
[X500] "Information Processing Systems - Open Systems Interconnec-
tion - The Directory: Overview of Concepts, Models and Ser-
vices", ISO/IEC JTC 1/SC21, International Standard 9594-1,
1988.
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[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.
[MIME-VCARD]F. Dawson, T. Howes, "VCard MIME Directory Profile", RFC
XXXX, March 1998.
[VCARD] Internet Mail Consortium, "vCard - The Electronic Business
Card", Version 2.1, http://www.imc.com/pdi/vcard-21.txt, Sep-
tember, 1996.
[RFC-2119] "Key words for use in RFCs to Indicate Requirement Levels",
RFC 2119, March 1997.
[RFC-2234] Crocker, D., Overell, P., "Augmented BNF for Syntax Specifi-
cations: ABNF", RFC 2234, November 1997.
19. Authors' Addresses
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
Frank Dawson
Lotus Development Corporation
6544 Battleford Drive
Raleigh, NC 27613
USA
frank_dawson@lotus.com
+1-919-676-9515
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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
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........................................5
5.8.1. Line delimiting and folding..................................5
5.8.2. ABNF content-type definition.................................6
5.8.3. Pre-defined Parameters.......................................7
5.8.4. Pre-defined Value Types......................................9
5.9. Applications which use this media type.........................12
5.10. Additional information........................................13
5.11. Person & email address to contact for further information.....13
5.12. Intended usage................................................13
5.13. Author/Change controller......................................13
6. Predefined Types.................................................13
6.1. SOURCE Type Definition.........................................14
6.2. NAME Type Definition...........................................14
6.3. PROFILE Type Definition........................................15
6.4. BEGIN Type Definition..........................................15
6.5. END Type Definition............................................16
7. Use of the multipart/related Content-Type........................16
8. Examples.........................................................17
8.1. Example 1......................................................17
8.2. Example 2......................................................17
8.3. Example 3......................................................18
8.4. Example 4......................................................19
9. Registration of new profiles.....................................20
9.1. Define the profile.............................................20
9.2. Post the profile definition....................................21
9.3. Allow a comment period.........................................21
9.4. Submit the profile for approval................................21
10. Profile Change Control..........................................21
11. Registration of new types.......................................22
11.1. Define the type...............................................22
11.2. Post the type definition......................................23
11.3. Allow a comment period........................................23
11.4. Submit the type for approval..................................23
12. Type Change Control.............................................23
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13. Registration of new parameters..................................24
13.1. Define the parameter..........................................24
13.2. Post the parameter definition.................................25
13.3. Allow a comment period........................................25
13.4. Submit the parameter for approval.............................25
14. Parameter Change Control........................................25
15. Registration of new value types.................................26
15.1. Define the value type.........................................26
15.2. Post the value type definition................................27
15.3. Allow a comment period........................................27
15.4. Submit the value type for approval............................27
16. Security Considerations.........................................27
17. Acknowledgements................................................28
18. References......................................................28
19. Authors' Addresses..............................................29
20. Table of Contents...............................................30
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