Comments on draft-saintandre-xmpp-uri-04.txt

Hello Pierre,

At the recent IETF, you asked me for (I18N) comments on
http://www.ietf.org/internet-drafts/draft-saintandre-xmpp-uri-04.txt.
Here they are, including quite some comments of a more general nature.

I have copied both the xmppwg list (given in the draft) and the uri
list. I'm not subscribed to the xmppwg list, so please cc me.

>Network Working Group                                     P. Saint-Andre
>Internet-Draft                                Jabber Software Foundation
>Expires: February 11, 2005                               August 13, 2004
>
>
>
>      A Uniform Resource Identifier (URI) Scheme for the Extensible
>                  Messaging and Presence Protocol (XMPP)
>                       draft-saintandre-xmpp-uri-04
>
>
>Status of this Memo
>
>
>    By submitting this Internet-Draft, I certify that any applicable
>    patent or other IPR claims of which I am aware have been disclosed,
>    and any of which I become aware will be disclosed, in accordance with
>    RFC 3668.
>
>
>    Internet-Drafts are working documents of the Internet Engineering
>    Task Force (IETF), its areas, and its working groups.  Note that
>    other groups may also distribute working documents as
>    Internet-Drafts.
>
>
>    Internet-Drafts are draft documents valid for a maximum of six months
>    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."
>
>
>    The list of current Internet-Drafts can be accessed at
>    http://www.ietf.org/ietf/1id-abstracts.txt.
>
>
>    The list of Internet-Draft Shadow Directories can be accessed at
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>
>
>    This Internet-Draft will expire on February 11, 2005.
>
>
>Copyright Notice
>
>
>    Copyright (C) The Internet Society (2004).  All Rights Reserved.
>
>
>Abstract
>
>
>    This document defines a Uniform Resource Identifier (URI) scheme for
>    use in addressing entities that can communicate via the Extensible
>    Messaging and Presence Protocol (XMPP).
>
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>Table of Contents
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>
>    1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
>      1.1   Terminology  . . . . . . . . . . . . . . . . . . . . . . .  3
>      1.2   Discussion Venue . . . . . . . . . . . . . . . . . . . . .  3
>    2.  Narrative  . . . . . . . . . . . . . . . . . . . . . . . . . .  3
>      2.1   Rationale  . . . . . . . . . . . . . . . . . . . . . . . .  3
>      2.2   Form . . . . . . . . . . . . . . . . . . . . . . . . . . .  4
>      2.3   Generation of XMPP URIs  . . . . . . . . . . . . . . . . .  4
>      2.4   Processing of XMPP URIs  . . . . . . . . . . . . . . . . .  5
>      2.5   Internationalization . . . . . . . . . . . . . . . . . . .  5
>    3.  xmpp: URI IANA Registration  . . . . . . . . . . . . . . . . .  6
>      3.1   URI scheme name  . . . . . . . . . . . . . . . . . . . . .  6
>      3.2   URI scheme syntax  . . . . . . . . . . . . . . . . . . . .  6
>      3.3   Character encoding considerations  . . . . . . . . . . . .  6
>      3.4   Intended usage . . . . . . . . . . . . . . . . . . . . . .  6
>      3.5   Security considerations  . . . . . . . . . . . . . . . . .  6
>      3.6   Relevant publications  . . . . . . . . . . . . . . . . . .  6
>      3.7   Person and email address to contact for further
>            information  . . . . . . . . . . . . . . . . . . . . . . .  7
>      3.8   Author/change controller . . . . . . . . . . . . . . . . .  7
>      3.9   Applications and/or protocols which use this URI
>            scheme name  . . . . . . . . . . . . . . . . . . . . . . .  7
>    4.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . .  7
>    5.  Security Considerations  . . . . . . . . . . . . . . . . . . .  7
>    6.  References . . . . . . . . . . . . . . . . . . . . . . . . . .  7
>    6.1   Normative References . . . . . . . . . . . . . . . . . . . .  7
>    6.2   Informative References . . . . . . . . . . . . . . . . . . .  8
>        Author's Address . . . . . . . . . . . . . . . . . . . . . . .  9
>    A.  Revision History . . . . . . . . . . . . . . . . . . . . . . .  9
>      A.1   Changes from draft-saintandre-xmpp-uri-03  . . . . . . . .  9
>      A.2   Changes from draft-saintandre-xmpp-uri-02  . . . . . . . .  9
>      A.3   Changes from draft-saintandre-xmpp-uri-01  . . . . . . . .  9
>      A.4   Changes from draft-saintandre-xmpp-uri-00  . . . . . . . .  9
>        Intellectual Property and Copyright Statements . . . . . . . . 10
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>1.  Introduction
>
>
>    The Extensible Messaging and Presence Protocol (XMPP) is a streaming
>    XML technology that enables near-real-time communications between any
>    two entities on a network.  [XMPP-CORE] specifies that on an XMPP
>    network itself, the address of an XMPP entity is not to be prepended
>    with a Uniform Resource Identifier (URI) scheme (as defined in RFC
>    2396 [URI]).

You should change RFC 2396 to
http://www.ietf.org/internet-drafts/draft-fielding-uri-rfc2396bis-06.txt,
or more exactly the RFC that will result from it (it's currently in
IETF Last Call).


>However, many applications external to an XMPP network
>    may need to address XMPP entities as full URIs; examples are
>    databases that need to store XMPP addresses and non-native user
>    agents (e.g., a web browser or calendaring application) that provide
>    an interface to XMPP services.  This memo defines an xmpp: URI scheme
>    for use by such applications, and conforms to both the requirements
>    in Registration Procedures for URL Scheme Names [URL-REG] and the
>    recommendations in Guidelines for new URL Schemes [URL-GUIDE].
>
>
>1.1  Terminology
>
>
>    This document inherits terminology described in [XMPP-CORE].
>
>
>    The capitalized 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 [TERMS].
>
>
>1.2  Discussion Venue
>
>
>    The author welcomes discussion and comments related to the topics
>    presented in this document.  The preferred forum is the
>    <xmppwg@jabber.org> mailing list, for which archives and subscription
>    information are available at
>    <<http://www.jabber.org/cgi-bin/mailman/listinfo/xmppwg/>>.
>
>
>2.  Narrative

I was quite confused by this title. Please change to something more
specific.


>2.1  Rationale
>
>
>    Many types of application can be built using XMPP.  The best-known
>    such application is instant messaging (IM) and presence (as these are
>    described in [IMP-MODEL] and [IMP-REQS] and defined for XMPP in
>    [XMPP-IM]).  Therefore it might seem appropriate

This is worded as if it actually isn't appropriate. But my understanding
is that you want to say is something like:

- It is appropriate to used the im: and pres: schemes for instant messaging
   and presence.
- There are other uses of XMPP, and the xmpp: scheme is for these other uses.


>to use the im: and
>    pres: URI schemes specified by Common Profile for Instant Messaging
>    (CPIM) [CPIM] and Common Profile for Presence (CPP) [CPP], rather
>    than to define an XMPP-specific URI scheme.  However, while the im:
>    and pres: URI schemes are appropriate for instant messaging and
>    presence applications and are therefore mentioned normatively in
>    [XMPP-IM], they are not necessarily appropriate for all XMPP
>    applications.  Because XMPP is fundamentally an XML streaming
>
>
>
>
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>    technology rather than an instant messaging and presence technology
>    per se, XMPP applications may conform to [XMPP-CORE] but not
>    [XMPP-IM] and thus not implement instant messaging and presence
>    semantics.  Indeed, XMPP is already used in applications such as
>    network management, workflow applications, generic publish-subscribe,
>    remote procedure calls, content syndication, gaming, and middleware.
>    These applications require an addressing scheme that is not tied to
>    the particular semantics of the im: and pres: URI schemes.
>    Therefore, this document defines a generic URI scheme that will
>    enable applications to address as a URI any entity that can
>    communicate via XMPP.
>
>
>    Note well that on an XMPP network, entities are to be addressed as
>    <[node@]domain[/resource]> (i.e., without a URI scheme) rather than
>    as <xmpp:[node@]domain[/resource]>.  The xmpp: URI format is provided
>    for the sake of non-native interfaces and applications only; native
>    applications are strongly encouraged

'strongly encouraged' sound as if there is no real harm (but really
no benefit) from using xmpp:[node@]domain[/resource]. Is this actually
true? Otherwise, I think it is better to write "native applications MUST
not use the xmpp: prefix", to make clear that this is an interoperability
requirement.


>not to prepend XMPP addresses
>    with the xmpp: URI scheme when addressing XML stanzas

The document sometimes talks about resources, and then sometimes about
stanzas. In an XMPP context, are they the same? Either streamline the
language (use 'resource' only), or explicitly say they are the same,
or be clearer about the difference.


>sent over an
>    XMPP network.
>
>
>2.2  Form
>
>
>    The syntax for an xmpp: URI is as follows (where the jid rule is
>    defined in [XMPP-CORE] and the query rule is defined in [URI]).
>
>
>          "xmpp:" jid [ "?" query ]

The change log says 'removed the query component', but it's still here.

For "jid", just referring to XMPP-CORE is way not enough, I guess.
The ABNF rules given in
http://www.ietf.org/internet-drafts/draft-ietf-xmpp-core-24.txt are:

       jid             = [ node "@" ] domain [ "/" resource ]
       domain          = fqdn / address-literal
       fqdn            = (sub-domain 1*("." sub-domain))
       sub-domain      = ([IDNA] conformant domain label)
       address-literal = IPv4address / IPv6address

For 'node' and 'resource', a stringprep profile is mentioned, which
seems to imply that these pieces can contain non-ASCII characters.
This would be in conflict with the general URI syntax.

For 'sub-domain', it mentions "a domain label as described in [IDNA]",
which would mean that it can not only be US-ASCII, but also binary
data. If that's what it should be, this would again be in conflict
with the general URI syntax. But my guess is that this is not what
is intended here; it's probably the case that 'fqnd' is supposed to
be what [IDNA] calls a "internationalized domain name", and sub-domain
is supposed to be what IDNA calls an *internationalized* domain label.
This again would be in conflict with the general URI syntax.

To make these cases work with URIs, what you have to do is to rework
the syntax rules so that where necessary (node, sub-domain, resource),
they include 'pct-encoded' from
http://www.ietf.org/internet-drafts/draft-fielding-uri-rfc2396bis-06.txt.
You then also have to be specific about what US-ASCII characters are
actually allowed directly (e.g. node doesn't contain '@', and so on),
based on the various examples in rfc2396bis and your stringprep
profiles.

One more thing: it seems that in your case, there are no [] delimiters
for IPv6address, and there is no mechanism for future ip protocol versions.
You may want to have a look at rfc2396bis to either bring this closer
to rfc2396bis or to explicitly mention that there is a difference.

>    An xmpp: URI is opaque rather than hierarchical, and thus is similar
>    to a mailto: URI as specified in RFC 2368 [MAILTO].  Because an xmpp:
>    URI is opaque, the XMPP address (or "JID") contained therein SHOULD
>    include only a node identifier (OPTIONAL) and domain identifier
>    (REQUIRED) as defined in [XMPP-CORE]; while an xmpp: URI MAY include
>    the resource identifier portion of a JID if the XMPP entity must be
>    addressed as such, as a general rule this is not encouraged since the
>    delimiter used before a resource identifier in XMPP addresses is the
>    slash character ("/"), which is discouraged by [URI] for opaque URIs.

There is no distinction between generic and opaque syntax anymore.
RFC2396bis now says:
"All URIs are parsed by generic syntax parsers when used. A URI scheme that
wishes to remain opaque to hierarchical processing must disallow the use of
slash and question mark characters. However, since a URI reference is only
modified by the generic parser if it contains a dot-segment (a complete path
segment of "." or "..", as described in Section 3.3), URI schemes may safely
use "/" for other purposes if they do not allow dot-segments."


>    While the "?" character is allowed in the resource identifier portion
>    of an XMPP address (according to [XMPP-CORE]), that character can be
>    used as a delimiter between the jid and the query parts of an xmpp:
>    URI; therefore, any instances of the "?" character in the resource
>    identifier portion of an XMPP address that is generated or processed
>    as an xmpp: URI MUST be escaped as "%3F" (as described in Section
>    2.2.5 of [URL-GUIDE]).

That's a good example of a case that should be expressed in the syntax
rules. The syntax has to express the exact form of the URI as it is
allowed to appear, not some intention about the parts that go into the
URI. So as an example, if the syntax for the resource identifier in
xmpp were something simple like
      resource = *( 'a' / 'b' / 'c' / '?' )
then the syntax for the resource component in the xmpp scheme syntax
would have to read:
      resource = *( 'a' / 'b' / 'c' / '%3F' / '%3f' )
or so.


>2.3  Generation of XMPP URIs
>
>
>    When generating an XMPP URI, the generating application SHOULD follow
>    these steps:

I'm probably repeating myself, but having these steps is in clear
conflict with the
     "xmpp:" jid [ "?" query ]
syntax rule above. Either there is an actual jid in there, or it's
something else that is the result of some processing. No shortcuts
allowed :-(.



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>    1.  Obtain XMPP address (JID).
>    2.  Perform [IDNA] translation against the JID (in the form of a
>        UTF-8 string).

What IDNA translation? The word 'translation' appears only once in
IDNA, in the copyright section. IDNA defines at least the ToASCII
operation and the ToUnicode operation, and it's not clear which
one you mean. And is this operation supposed to be applied to
the whole JID, including node and resource?
Also, UTF-8 is only given in examples in IDNA, and it's not clear
what it is supposed to do here.


>    3.  Verify that the UTF-8 string conforms to the format defined in
>        [XMPP-CORE], including all appropriate [STRINGPREP] profiles.

Since when do stringprep profiles apply to UTF-8? Aren't they much
more general? What if somebody wants to implement these operations
in UTF-16?


>    4.  Convert any bytes that are not US-ASCII (see [ASCII]) to %hexhex
>        format as described in Section 2.2.5 of [URL-GUIDE].

I think it would be very helpful to be a bit more specific here
and to mention UTF-8. In this step, it's actually relevant.


>    5.  Prepend the 'xmpp:' scheme.
>    6.  Append the query component, if any.



>2.4  Processing of XMPP URIs
>
>
>    When processing an XMPP URI, the processing application SHOULD follow
>    these steps:
>
>
>    1.  Obtain URI.
>    2.  Convert any parts in %hexhex format to UTF-8 as described in
>        Section 2.2.5 of [URL-GUIDE].
>    3.  Verify that the UTF-8 string conforms to the format defined in
>        [XMPP-CORE], including all appropriate [STRINGPREP] profiles.
>    4.  Perform [IDNA] translation against the UTF-8 string.
>    5.  Extract the XMPP address by removing the 'xmpp:' scheme and the
>        query component (if any).

Very similar comments to above apply here.


>    At this point, the processing application would either (1) complete
>    further XMPP handling itself or (2) invoke a helper application to
>    complete XMPP handling; such XMPP handling would most likely consist
>    of the following steps:
>
>
>    1.  Authenticating with an appropriate XMPP server (e.g., a server
>        that a user has configured as his or her registered service
>        provider) if not already authenticated.
>    2.  Optionally determining the nature of the intended recipient
>        (e.g., via [DISCO]).
>    3.  Optionally presenting an appropriate interface to a user based on
>        the nature of the intended recipient and/or the contents of the
>        query component (however, if the application does not understand
>        the query component, it MUST ignore the query component and treat
>        the URI as consisting of "xmpp:jid" rather than
>        "xmpp:jid?query").

What's the secret recipie of understanding the query component?
I assume that 'application' means 'client application', because the
interface is presented by the client. But clients are not supposed
to understand the query component.


>    4.  Generating an XMPP stanza that translates any user or application
>        inputs into their corresponding XMPP equivalents.
>    5.  Sending the XMPP stanza via the authenticated server connection
>        for delivery to the intended recipient.

At this point, I realized that there isn't a single example in this
document. Some examples of xmpp scheme URIs would definitely help,
both US-ASCII only and others that included non-ASCII text via
%HH (I can help).

Also, examples of the above steps would be great.



>2.5  Internationalization
>
>
>    By definition, an XMPP URI is also an Internationalized Resource
>
>
>
>
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>    Identifier (see [IRI]).

By definition, any URI, even something as simple as http://www.jabber.org,
is an IRI. Not worth mentioning.

What you should say is that xmpp URIs, because they use UTF-8 and %HH
to encode non-ASCII characters, are designed to work well with IRIs,
in particular that except for the stringprep verification and issues
with syntax-relevant US-ASCII characters such as the '?', an XMPP
IRI can directly be constructed by prepending "xmpp:" to a jid.



>As specified in [XMPP-CORE], each portion of
>    a JID (node identifier, domain identifier, resource identifier) is
>    allowed to be a fully internationalized string in accordance with
>    various profiles of [STRINGPREP]; any non-US-ASCII characters in such
>    strings (as well as any byte that is not in the set
>    a-zA-Z0-9!$*.?_~+=) MUST be properly transformed to %hexhex format as
>    described in Section 2.2.5 of [URL-GUIDE].

This part should probably come before the text about IRIs in this section.
And please mention UTF-8 when talking about Section 2.2.5 of [URL-GUIDE].


>3.  xmpp: URI IANA Registration
>
>
>    This section provides the information required to register the xmpp:
>    URI scheme.
>
>
>3.1  URI scheme name
>
>
>    xmpp
>
>
>3.2  URI scheme syntax
>
>
>    The syntax for an xmpp: URI is defined below using Augmented
>    Backus-Naur Form as specified by [ABNF].  The jid rule is defined in
>    [XMPP-CORE].
>
>
>    XMPP-URI = "xmpp:" jid [ "?" query ]
>
>
>
>3.3  Character encoding considerations
>
>
>    Representation of non-US-ASCII character sets

Why 'character sets'? Why not just 'characters'?


>in local-part strings

The term 'local-part string' turns up for the first time here.

>    is limited to the standard methods provided as extensions to RFC 2822
>    [IMF].

I have no clue why RFC 2822 is mentioned here. Does it allow %HH?


>Specifically, for each byte, if the byte is not in the set
>    a-zA-Z0-9!$*.?_~+= then transform the byte to %hexhex format as
>    described in Section 2.2.5 of [URL-GUIDE].

Again, please mention UTF-8 when talking about Section 2.2.5 of [URL-GUIDE].


>3.4  Intended usage
>
>
>    The xmpp: URI is intended to be used by interfaces to an XMPP network
>    from non-native user agents such as web browsers, as well as by
>    non-native applications that need to address XMPP entities as full
>    URIs.
>
>
>3.5  Security considerations
>
>
>    See Security Considerations (Section 5) of XXXX.
>
>
>3.6  Relevant publications
>
>
>    [XMPP-CORE]
>
>
>
>
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>
>3.7  Person and email address to contact for further information
>
>
>    Peter Saint-Andre [mailto:stpeter@jabber.org]
>
>
>3.8  Author/change controller
>
>
>    This scheme is registered under the IETF tree.  As such, the IETF
>    maintains change control.
>
>
>3.9  Applications and/or protocols which use this URI scheme name
>
>
>    Applications (other than native native XMPP applications) that
>    provide an interface to XMPP services or that need to address XMPP
>    entities as full URIs.
>
>
>4.  IANA Considerations
>
>
>    This entire document addresses IANA considerations.

Change to something like: This document registers an URI scheme.
The registration template is in section 3.


>5.  Security Considerations
>
>
>    Detailed security considerations for XMPP are given in [XMPP-CORE].
>    Providing an interface to XMPP services from non-native applications
>    introduces new security concerns.  For example, the ability to
>    interact with XMPP entities via a web browser may expose sensitive
>    information to attacks that are not possible or that are unlikely on
>    a native XMPP network.  Due care must be taken in deciding what
>    information is appropriate for representing in xmpp: URIs; in
>    particular, passwords MUST NOT be represented.

How would I represent a password in the first place?


>6.  References
>
>
>6.1  Normative References
>
>
>    [ABNF]     Crocker, D. and P. Overell, "Augmented BNF for Syntax
>               Specifications: ABNF", RFC 2234, November 1997.
>
>
>    [IMF]      Resnick, P., "Internet Message Format", RFC 2822, April
>               2001.
>
>
>    [TERMS]    Bradner, S., "Key words for use in RFCs to Indicate
>               Requirement Levels", BCP 14, RFC 2119, March 1997.
>
>
>    [URI]      Berners-Lee, T., Fielding, R. and L. Masinter, "Uniform
>               Resource Identifiers (URI): Generic Syntax", RFC 2396,
>               August 1998, <http://www.ietf.org/rfc/rfc2396.txt>.
>
>
>    [URL-GUIDE]
>
>
>
>
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>
>
>               Masinter, L., Alvestrand, H., Zigmond, D. and R. Petke,
>               "Guidelines for new URL Schemes", RFC 2718, November 1999.
>
>
>    [URL-REG]  Petke, R. and I. King, "Registration Procedures for URL
>               Scheme Names", BCP 35, RFC 2717, November 1999.
>
>
>    [XMPP-CORE]
>               Saint-Andre, P., "Extensible Messaging and Presence
>               Protocol (XMPP): Core", draft-ietf-xmpp-core-22 (work in
>               progress), January 2004.
>
>
>    [XMPP-IM]  Saint-Andre, P., "Extensible Messaging and Presence
>               Protocol (XMPP): Instant Messaging and Presence",
>               draft-ietf-xmpp-im-21 (work in progress), January 2004.
>
>
>6.2  Informative References
>
>
>    [ASCII]    American National Standards Institute, "Coded Character
>               Set - 7-bit American Standard Code for Information
>               Interchange", ANSI X3.4, 1986.
>
>
>    [CPIM]     Peterson, J., "Common Profile for Instant Messaging
>               (CPIM)", draft-ietf-impp-im-04 (work in progress), August
>               2003.
>
>
>    [CPP]      Peterson, J., "Common Profile for Presence (CPP)",
>               draft-ietf-impp-pres-04 (work in progress), August 2003.
>
>
>    [DISCO]    Hildebrand, J., Millard, P., Eatmon, R. and P.
>               Saint-Andre, "JEP-0030: Service Discovery", June 2004,
>               <http://www.jabber.org/jeps/jep-0030.html>.
>
>
>    [IDNA]     Faltstrom, P., Hoffman, P. and A. Costello,
>               "Internationalizing Domain Names in Applications (IDNA)",
>               RFC 3490, March 2003.
>
>
>    [IMP-MODEL]
>               Day, M., Rosenberg, J. and H. Sugano, "A Model for
>               Presence and Instant Messaging", RFC 2778, February 2000.
>
>
>    [IMP-REQS]
>               Day, M., Aggarwal, S. and J. Vincent, "Instant Messaging /
>               Presence Protocol Requirements", RFC 2779, February 2000.
>
>
>    [IRI]      Duerst, M. and M. Suignard, "Internationalized Resource
>               Identifiers (IRI)", draft-duerst-i18n-iri-06 (work in
>               progress), February 2004.

This is now draft-duerst-i18n-iri-09. And you should write it as
RFC ZZZZ, with instructions to the RFC editor to change to the actual
number. Same for RFC 2396bis.


Regards,    Martin.






>Saint-Andre            Expires February 11, 2005                [Page 8]
>Internet-Draft                  XMPP URI                     August 2004
>
>
>
>    [MAILTO]   Hoffman, P., Masinter, L. and J. Zawinski, "The mailto URL
>               scheme", RFC 2368, July 1998.
>
>
>    [STRINGPREP]
>               Hoffman, P. and M. Blanchet, "Preparation of
>               Internationalized Strings ("STRINGPREP")", RFC 3454,
>               December 2002.
>
>
>
>Author's Address
>
>
>    Peter Saint-Andre
>    Jabber Software Foundation
>
>
>    EMail: stpeter@jabber.org
>
>
>Appendix A.  Revision History
>
>
>    Note to RFC Editor: please remove this entire appendix, and the
>    corresponding entries in the table of contents, prior to publication.
>
>
>A.1  Changes from draft-saintandre-xmpp-uri-03
>
>
>    o  Removed query component.
>    o  Clarified URI generation and processing rules in accordance with
>       XMPP WG list discussion.
>
>
>A.2  Changes from draft-saintandre-xmpp-uri-02
>
>
>    o  Corrected several small textual errors.
>    o  Clarified the scope of allowable presence information.
>
>
>A.3  Changes from draft-saintandre-xmpp-uri-01
>
>
>    o  Clarified guidelines for escaping of UTF-8 characters.
>    o  Specified usage of query component.
>
>
>A.4  Changes from draft-saintandre-xmpp-uri-00
>
>
>    o  Modified ABNF to track changes to XMPP Core.
>    o  Clarified a few matters in the text.
>
>
>
>
>
>
>
>
>
>
>
>Saint-Andre            Expires February 11, 2005                [Page 9]
>Internet-Draft                  XMPP URI                     August 2004
>
>
>
>Intellectual Property Statement
>
>
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>Saint-Andre            Expires February 11, 2005               [Page 10]

Received on Thursday, 19 August 2004 08:11:39 UTC