Applications Area

Directors:


   o Harald Alvestrand:  Harald.T.Alvestrand@uninett.no
   o John Klensin:  Klensin@mail1.reston.mci.net


Area Summary reported by John Klensin/MCI and Harald Alvestrand/UNINETT

This is a report on the status of the Applications Area as of the
conclusion of the Stockholm IETF meeting, July 1995.

The Applications Area currently contains the following working groups:


   o Access, Searching and Indexing of Directories (ASID)
   o Detailed Revision/Update of Message Standards (DRUMS)
   o HyperText Markup Language (HTML)
   o HyperText Transfer Protocol (HTTP)
   o Integrated Directory Services (IDS)
   o Mail Extensions (MAILEXT)
   o MIME Content-Type for SGML Documents (MIMESGML)
   o MIME - X.400 Gateway (MIXER)
   o Notifications and Acknowledgements Requirements (NOTARY)
   o Uniform Resource Identifiers (URI)


Of these, DRUMS is new since the last IETF. The MIXER Working Group has
evolved from the previous MIXER Advisory Committee (see the April 1995
Area Report).  The HTTP Security BOF (HTTPSEC) held in San Jose has
evolved into the Web Transaction Security Working Group (WTS), jointly
managed in the Security and Applications Areas.  HTTP is jointly
supervised with the Transport Area.  IDS and URI are jointly supervised
with the User Services Area.

The Electronic Data Interchange Working Group (EDI) concluded its work
since the last IETF. Publication of its final product, a Frequently
Asked Questions (FAQ) document, is pending.  The Internet White Pages
Requirements Working Group (WHIP) concluded since the last IETF. Some
documents were transferred to the IDS Working Group.  The Quality
Information Services Working Group (QUIS) was also concluded, as
discussed in the last Area Report.  Finally, the URI Working Group
concluded its work during this IETF. See its minutes and discussion
below for more information.

The Applications Area sponsored three BOF sessions on mime-related media
type registration (MIMEREG), content labelling of Web and other Internet
materials (RTL), and mail read receipts (RECEIPT) at the Stockholm IETF.
The RTL BOF was jointly sponsored with User Services and the minutes of
that meeting are reported under the User Services section of these
proceedings.  Summaries of each of the BOFs is reported below.



MIME Registration BOF (MIMEREG)

Registration procedures for MIME content types have been evolving since
MIME was first approved as a Proposed Standard and these definitions
began to be used in the World Wide Web and in other Internet
applications.  They are now referred to as media types to reflect their
broader application.  The current registration procedures call for
exposure of a potential new type on a mailing list followed by review of
consensus and the adequacy of the registration and description.  This
procedure has probably worked better than its predecessors, but the
burden on the reviewer has proved excessive.

The MIME standard also specifies that new top-level types can be
defined, but discourages the registration of many of these and requires
that registration be accomplished by standards-track processing.

A BOF session was held in Stockholm to review the general strategy for
media type registrations and to examine the top-level type question,
especially with regard to a proposal to register `chemical' as a
top-level type.  Opinions on the latter subject are divided in IETF,
occupying the entire range between ``no further top-level types should
be registered'' and ``registration for top-level types should be fairly
permissive.''  The BOF was inconclusive and further exploration in this
area will be needed.


Read the Label BOF (RTL)

In the recent past, a number of public concerns about limiting access to
information on the Internet have been raised.  Most of these concerns
have taken the form of calls for access limits for minors who might
otherwise be exposed to material considered suitable only for adults.
Countervailing concerns about the potential for censorship have been
raised in response.  After brief background remarks by the chair, a
discussion followed, the purpose of which was to determine the level of
interest among the BOF participants in forming an IETF Working Group to
develop technical specifications supporting voluntary information
filtering through appropriate, end-user access software.  The results of
the technical effort would permit users of the Internet to apply some
form of content filtering on information obtained from Web servers, file
servers, e-mail servers and other sources of information found on the
Internet.  For concreteness, the discussion tended to fall back on an
implicit Web browser/server model of the problem, but it was
acknowledged that the general problem was more complex and that
solutions should apply to all forms of information on the Internet.

Conclusions:


   o The IETF should investigate technical possibilities for filtering
     and access controls which could be voluntarily invoked by users and
     voluntarily supported by information service suppliers.

   o A short-term working group charter should be prepared which would
     explore technical means for creating closed groups of
     clients/servers.  A particular client might participate in more
     that one closed server group.  This was recognized as a coarse form
     of content filtering at the level of entire servers, and thus a
     very crude means of addressing the problem.

   o A longer term working group should be considered which would
     explore finer-grained filtering capabilities, possibly using
     `metadata' techniques.

   o Not all information in the Internet is likely to be marked, so any
     proposals for filtering and access control will have to deal with
     unmarked Internet information components.



Receipt Notifications for Internet Mail BOF (RECEIPT)

About 60 participants agreed to add read receipt functionality to
Internet mail.  The charter for the working group has been accepted.
The author of the specification is Roger Fajman, who promised a first
draft by end of August.  A first technical solution has been drafted
already to support functionality based on the NOTARY work.  Most of the
available time has been spent to find out what exactly the requirements
are seen both from the sender's and from the recipient's point of view.
There is no consensus yet.  Privacy and security issues are a topic of
the working group but will be postponed until first experience has been
gained.



Access, Searching and Indexing of Directories Working Group (ASID)

LDAPv2 was discussed, with a draft promised by the Dallas IETF. One
candidate (MDAP) was presented at the meeting, as was a different
proposal for strong authentication/encryption of the LDAP session, and
for supporting stand-alone LDAP.

The two Whois++ protocol documents have been approved.  The indexing
document is still awaiting some issues to be resolved.  A discussion was
held on various protocol aspects that have surfaced during
implementation.

The common indexing protocol draft was discussed.  The group feels it
still needs to be more general, separated from Whois++.  Referrals need
to be URL-style, Whois++ queries need to be dropped, etc.  People should
send comments to the list, after which a new draft will be submitted.

An Internet-Draft for storing PGP keys in the X.500 directory was
discussed and approved by the group, following some changes to the
string representation used for the keys.

A new charter was approved, with updated milestones.


Detailed Revision/Update of Message Standards Working Group (DRUMS)

The DRUMS Working Group held its first meeting at the Stockholm IETF
with about 50 people in attendance.  Since the group was only recently
formed and did not yet have any documents to review, the working group
meeting time was used to (a) list several important issues which might
be difficult to resolve on a mailing list, and (b) to discuss in detail
one of those issues:  whether to change the grammar of RFC 822 to remove
``.'', ``['', and ``]'' as terminal symbols and thus allow them to
appear in ``phrase''s.  The discussion which ensued illustrated the
difficulty of deciding whether to ``fix'' features of the existing
protocol which are widely regarded as broken, when the ``fix'' would
adversely impact the installed base.  A suggestion was made that each
such decision be made only after a careful analysis of cost vs.
benefit.  Since several other issues involve tradeoffs of this kind, the
chair directed that a discussion of such tradeoffs and how to think
about them, be held on the mailing list, as a prerequisite to further
discussions about changes to the actual protocols.


HyperText Markup Language Working Group (HTML)

The HTML Working Group reviewed goals for moving forward with various
HTML extensions, including tables, metadata, super/subscripts, and
internationalization.  A firm goal was set for clear progress on tables,
which are close to Last Call status.


HyperText Transfer Protocol Working Group (HTTP)

The agenda called for a discussion of the HTTP 1.0 and 1.1 documents,
and a proposal for multiple transactions per connection.  As the editors
of the documents were not present, the discussions were brief.  The
chair noted that the milestones were out of date.  The Area Director
raised considerable concern over the lack of progress and coordination
in the working group.  A constructive discussion of the milestones of
the working group concluded the meeting.


Integrated Directory Services Working Group (IDS)

Reporting on pilot projects and liaison reports will be done on the IDS
mailing list in the future to free up time in the working group meeting.
Both the Whois++ and X.500 directory catalogues are now available
on-line and currently in the process of setting up a procedure for
adding in new implementation entries.  There was a lot of discussion on
the X.500 schema registry and the conclusion was to try and focus on
getting this operational as soon as possible.  The Internet-Draft will
be reissued within the next month.  A proposal for managing the X.500
root context was discussed along with two Internet-Drafts on building a
directory service, one based in the US and one based in the Netherlands.
The group felt that it was important to disseminate practical experience
gained to as wide an audience as possible.

IDS took over the Simple Internet White Pages documents at this meeting
and decided to go for two documents:  user requirements and schema
requirements.  This information will be pulled from the existing WHIP
document and the Internet-Drafts will be circulated by the end of
August.


Mail Extensions Working Group (MAILEXT)

MAILEXT did not meet during the Stockholm IETF. Its work is
substantially complete; the remaining documents are being polished and
undergoing final review before being submitted to the IESG.


MIME Content-Type for SGML Documents Working Group
(MIMESGML)

Due to a combination of circumstances, the MIMESGML Working Group met
without either of the co-chairs present.

The working group seems to be at a choice point with one complete
proposal on the table but a significant fraction of the working group
preferring other alternatives.  That situation was discussed during the
working group meeting and objections to the current draft were discussed
among the attendees in Stockholm and on the MBONE. Details of the issues
discussed appear in the working group minutes.  Don Stinchfield from EBT
volunteered that he would author a new draft for this group that was
more general, included a discussion of difficulties with the current
draft, and still followed the direction of the charter.  This draft will
be posted to the mailing list in August.


MIME - X.400 Gateway Working Group (MIXER)

About 40 participants, of which three are actual implementors of
RFC 1327, participated at the meeting.  A list of 16 open topics
streamlined the discussion.  The issue on how much ESMTP functionality
should be mandatory for MIXER gateways needs more study and has been
moved onto the mailing list.  All other issues have been solved.  There
will be a one-day editor's meeting for page-by-page review at Richmond
UK, 17 September.  An updated version is expected soon after that
meeting.

The MIXER document handling body part mappings will be split to reduce
the number of needed updates.  The bit ordering for G3 faxes will be
checked with more implementors to get as much agreement as possible.


Notifications and Acknowledgements Requirements Working Group
(NOTARY)

The NOTARY group did not meet in Stockholm.  It believes that its work
is finished with the IETF Last Call on its documents.  Some comments
came in during and after the Last Call period; a report on these will be
sent.


Uniform Resource Identifiers Working Group (URI)

While the URI working group has completed all of the items in its
original charter, ongoing efforts have identified several additional
work items related to resource identifiers that should be pursued.  At
the same time, the working group had become sufficiently large and
diffuse that some proposals for, e.g., new URL types, were not getting
comprehensive review.

In Stockholm, the working group met, heard reports on work in progress
and being proposed, and discussed but did not reach conclusion on a
proposal for a revised charter.  The working group was advised by the
Area Director, John Klensin, that general IETF procedures called for
concluding the working group and starting one or more new ones as needed
and that highly focused working groups with short time frames and clear
objectives were preferred to more open-ended ones.  He also reminded the
working group that IETF's success record with standardizing research
activities has been very poor and discouraged the working group from
embarking on activities that still lack a foundation in practice.

There were additional discussions in the days after the working group
met, culminating in a special BOF session to review options for future
work and working groups.  Several proposals were outlined.  They will be
proposed in more detail on the URI Working Group mailing list and, if
sufficient constituency and focus exists, submitted for approval as new
working groups.

The URI Working Group was concluded at the close of the IETF meeting.