Internet DRAFT - draft-arkko-iesg-crossarea
draft-arkko-iesg-crossarea
Network Working Group J. Arkko
Internet-Draft Ericsson
Intended status: Informational February 7, 2013
Expires: August 11, 2013
Experiences from Cross-Area Work at the IETF
draft-arkko-iesg-crossarea-03
Abstract
This memo discusses the reasons for IETF work on topics that cross
area boundaries. Such cross-area work presents challenges for the
organization of the IETF as well as on how interested parties can
participate the work. The memo also provides some suggestions on
managing these challenges.
Status of this Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.
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."
This Internet-Draft will expire on August 11, 2013.
Copyright Notice
Copyright (c) 2013 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Arkko Expires August 11, 2013 [Page 1]
Internet-Draft Cross-Area Work February 2013
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Examples of Cross-Area Work . . . . . . . . . . . . . . . . . 3
3. Rationale for Cross-Area Work . . . . . . . . . . . . . . . . 4
4. Challenges . . . . . . . . . . . . . . . . . . . . . . . . . . 5
5. Ten Recommendations . . . . . . . . . . . . . . . . . . . . . 8
6. Informative References . . . . . . . . . . . . . . . . . . . . 10
Appendix A. Acknowledgments . . . . . . . . . . . . . . . . . . . 10
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 11
Arkko Expires August 11, 2013 [Page 2]
Internet-Draft Cross-Area Work February 2013
1. Introduction
This memo discusses IETF work that crosses area boundaries. Some
examples about such work are given in Section 2. The reasons for
initiating work that involves cross-area aspects are discussed in
Section 3. From the perspective of a participant interested in a
specific effort, the area designations matter little. If the work is
interesting, the necessary people come to the meetings and work on
the specifications. However, cross-area work does present some
challenges for the organization of the IETF as well as on how
interested parties can participate the work. These issues are
discussed in Section 4. Finally, Section 5 provides some suggestions
on managing these challenges in an effective way.
2. Examples of Cross-Area Work
Many IETF efforts cross area boundaries. Some recent examples of
such work include:
o The development of a routing-protocol based bridging model. This
work has been going on in the TRILL WG on the Internet Area and in
parallel in the ISIS WG on the Routing Area.
o The work that started in 2008-2009 to address impending IPv4
address runout and remaining needs for transition mechanisms to
support IPv6 deployment. This was worked on in the V6OPS WG on
the Operations and Management Area, in the BEHAVE WG on the
Transport Area, and in the SOFTWIRE WG on the Internet Area.
o The HOMENET WG is developing automatic provisioning tools for home
networks and will require assistance from, for instance, Routing
Area WGs to build the necessary routing protocol zero-
configuration extensions.
o The RENUM WG on the Operations and Management Area is addressing
renumbering issues, but will have to work with other areas if
changes or extensions to specific protocols are required.
o The allocation of a new private address space to employ a shared
address for multiple subscribers in networks employing NAT44 was
discussed in the INTAREA, OPSAREA, BEHAVE, and V6OPS WGs.
o The LWIG WG on the Internet Area is documenting existing practices
for creating lightweight implementations of the TCP/IP stack and
application protocols. Specific recommendations on transport and
application protocols obviously need participation from those
areas, however.
Arkko Expires August 11, 2013 [Page 3]
Internet-Draft Cross-Area Work February 2013
o The Routing Area, Transport Area, and Security Area have worked
together on security mechanisms and key management tools necessary
to secure BGP sessions carried on top of TCP. For instance, the
SIDR and KARP WGs are in the Routing Area, but they are clearly
focused on topics that are generally found in the Security Area.
o Many IETF topics involve operational aspects as well as protocol
development. For instance, issues with address selection policies
have been discussed in the V6OPS WG on the Operations and
Management Area, and solutions for these problems were taken up by
the 6MAN WG on the Internet Area.
3. Rationale for Cross-Area Work
From an IETF participant's point of view, it is important that there
is a working group where the technical topic that he or she is
interested in can be discussed. The area and the management
structure matters little for this, as long as the working group can
work on all of the relevant aspects. These aspects, may, however,
involve different types of expertise or topics commonly handled in
different groups of people at the IETF. Cross-area work is needed,
of course, in any situation where a particular technical problem does
not cleanly map to one organization. For instance, some problems may
be more about the entire system than any individual node or protocol
layer. The work done in the RENUM and LWIG WGs falls into this
category, for instance.
In other cases different types of individuals may have specific
expertise that is helpful to solve a problem. For instance, some
models of interworking between IPv4 and IPv6 required expertise from
the specialists on IPv6 on the Internet Area and the specialists on
translation tools on the Transport Area. A common form of providing
expertise from multiple areas involves operational aspects and
protocol development. Such work often happens in a sequential
manner. The operators first discuss practical problems, then provide
suggestions for operational ways to contain the problems, and
eventually may ask for new solutions to reduce these problems. The
actual solution work is then taken up by the relevant technical
community that works on the protocol that needs to be extended.
Another common example of a situation where two different areas of
expertise are needed is developing security features for a protocol.
The protocol specialists are needed to understand the application and
its requirements and the security specialists are needed to help with
understanding the possible security issues and potential solutions.
Such work is commonly not organized as cross-area work, however.
Typically, a "security advisor" is assigned to a protocol working
Arkko Expires August 11, 2013 [Page 4]
Internet-Draft Cross-Area Work February 2013
group. The advisor and other security experts merely attend the
group. The advisor model is used in other instances as well,
including MIB doctors and routing area expertise. However, in some
cases the need to work together goes beyond such individual
participation. For instance, the security mechanisms and their key
management tools necessary to secure BGP sessions carried on top of
TCP have led to the creation of significant efforts both in the
Routing and Security Areas.
Sometimes a large body of work is split into different parts merely
to spread the workload. The IPv6 transition topic has been so big
for the IETF that part of the reason for splitting the work to three
areas was to ensure there was enough participants, chairs, and area
directors to handle the workload.
4. Challenges
Cross-area work does present some challenges, however. Apart from
the advisor model there are no established practices and the
processes and division of responsibility differs from case to case
[RFC2026].
Some of the issues include:
Fuzzy Hot Topics
Many recently proposed "hot" areas of work for the IETF have been
on vaguely defined topics that cover many possible areas. For
instance, work on new technologies for data centers or cloud
computing. In many cases it is unclear if the topic is truly a
cross-area topic for some fundamental reason, or if the IETF has
just not succeeded yet in teasing out concrete tasks from this
topic. For instance, operational and performance problems are
often discussed in Operations & Management area working groups.
Sometimes, after some analysis, these problems turn out to be
something where protocol modifications or extensions would help.
But as soon as such a conclusion is made, it typically falls on
other areas to make the actual modifications. Typically, there
are existing working groups that are responsible for the
technology in question.
Area Shopping
If the IESG does not manage the process in an coordinated manner,
this can lead to "area shopping" where a particular topic is being
discussed in several areas and working groups and may be taken up
in one area even if dismissed in others. This may be fine, if the
Arkko Expires August 11, 2013 [Page 5]
Internet-Draft Cross-Area Work February 2013
decision is made due to the topic fitting better an area. But it
is also possible that concerns raised in one forum are not
understood in another, and this can lead to an effort going
forward after finding the "lowest bar" forum to take it up.
Lack of Common IESG Vision
In many of the complex cross-area topics, the IESG has initially
had no strategy on how the work shall be divided, or even a common
set of goals. The IESG has also had several internal arguments
over some topics. Clearly, establishing a common vision between
the relevant ADs for how to proceed with a given topic is
essential for a successful outcome. Part of the problem here is
that IESG does not normally develop a master plan, but rather
individual documents and charter proposals are brought to the IESG
in a piecemeal fashion, one by one. This makes it hard to see
bigger trends and possibilities for colliding work.
Similarly, the yearly changes to the people on the IESG may change
the position that IESG members have on a topic, which can lead to
surprises to the community and new discussions in the IESG.
These problems exist both for specific efforts and the general
strategies for handling cross-area work. IESG members have had
varying opinions on whether to create specific, formally
recognized cross-area working groups or handle them in some other
way.
Problem Ownership
A more common issue is that the different organizations typically
have different motivations. A group of developers may be very
interested in solving, say, a bridging problem in a particular
way, and they are funded full-time by their employers to get this
work done. If this group is dependent on some other people on
making changes to a technology that they are in charge of, it is
likely that there is not a similar level of commitment. The other
people are unlikely to be able to spend all their time on this
project, for instance. This creates an eventual tussle between
different interests and may lead to frustration and different
expectations on the timelines necessary for the work.
Of course, the other side of the issue is that in most cases it
would not be a good idea to let the first group develop the
necessary changes by themselves either. Often the second group is
the true expert on the technology and needs to be involved in
order for a change to be done so that it does not cause breakage
elsewhere.
Arkko Expires August 11, 2013 [Page 6]
Internet-Draft Cross-Area Work February 2013
Rigid Topic Ownership
A related issue is that topic ownership should not necessarily be
static over time. Sometimes it makes sense to review and change
the area that is responsible for a particular topic. Many working
groups and topics have moved back and forth between Internet and
Routing or Applications and Transport areas, for instance.
Periodic review and re-assessment is healthy and encouraged.
Similarly, requests for cross-area review are relatively
infrequent or sent only to a particular subset of people in an
area (such as a directorate). For the regular participant it is
difficult to find out where there are important documents that
would deserve more review.
Attention Focus
It is natural for the leaders of an organization to develop a
closer relationship with work within their own part of the
organization. An AD may make a status check with his own WG
chairs, for instance, but not with those on neighboring areas
working on another half of some common topic.
Scheduling
Current IETF scheduling principle is centered around a sequences
of meetings of working groups in the same area. This makes it
possible for someone to follow all meetings in his or her area,
and enables the ADs to attend all the meetings they have to.
Cross-area work breaks this principle, as, for instance, technical
experts on some commonly used technology now may have to attend a
meeting from another area. The same applies to ADs and chairs.
This has been a practical problem for Internet Area ADs, for
instance, as they have to attend V6OPS and BEHAVE WG meetings in
addition to ones in their own area, but this is not readily
apparent to the people who perform scheduling.
Process vs. Substance
In recent years there has been a tendency to take up
organizational discussions in the precious few hours that we have
for face-to-face discussions at the IETF. The author believes
that it would be most useful to reserve the face-to-face
discussion time for the difficult technical topics, and the
relevant chairs and ADs should decide organizational matters off-
line after a consultation with the relevant mail list.
Cross-area and cross-WG work, duplicated presentations in multiple
Arkko Expires August 11, 2013 [Page 7]
Internet-Draft Cross-Area Work February 2013
forums, and formal messages between groups are usually not good
signs about the health of a standards organization. Too much time
may be spent on internal discussions, and too little on technical
substance, running code, and customer or user input.
Incentives
Ultimately, motivation determines the effort that IETF
participants will make toward topics that are not part of their
primary goals or day job requirements. The participants are
volunteers that do not have time to keep up with unlimited number
of mailing lists and documents. Some of them may end up following
some topics based on attending a meeting that they found
interesting. Some of them may end up doing something because
someone else requested them to look at a particular issue. And
some may dig into a topic based on hearing about in the hallways
of an IETF meeting. But in general, there is limited opportunity
and bandwidth for looking into new topics.
5. Ten Recommendations
There are no hard and fast rules for complex development efforts that
span multiple areas of expertise. However, the author believes that
experience has shown the following guidelines can improve the
situation in many cases.
1. Complex organizational structure should not be initiated
lightly. It should be reserved for situations that truly demand
it. Re-organization and moving responsibilities to one place
should be considered as alternatives.
2. People matter, organizations do not. The essence of most cross-
area work is getting the right expertise to the room and to the
mail list. This does not happen through mere organizational
forms, people have to be interested in the problem.
Example: The IPv6 transition problem has been such an
interesting issue for a large class of IETF contributors that
a significant number of key participants appear in the
relevant meetings no matter what area or working group they
are under.
3. Chair and advisor selection. Given that people matter, many
cross-area issues can be solved through assigning suitable
people to act as chairs and technical advisors. For instance,
many groups have one chair focused on protocol aspects and
another one focused on operational aspects. Typically, the
Arkko Expires August 11, 2013 [Page 8]
Internet-Draft Cross-Area Work February 2013
first type of a chair has protocol design and implementation
experience in the topic, and the second one may be operating
networks and may have an Operations and Management Area
background.
4. Cross-area review. Similarly, expertise is not brought in by an
area designation, it is brought through the right people
actually commenting on the specifications. Encouraging cross-
area review is therefore helpful, for instance through
directorates assigned to review important documents from other
areas.
5. Ensure that the IESG has a clear understanding of the topic area
and the plan ahead. It is recommended that the IESG discusses
the division of responsibilities and the plan for any major
cross-area effort upfront, and documents the agreed plan in
writing. Plans may naturally have to be revisited, as
understanding the needs for further work is a continuous
process. In addition, as the membership of the IESG evolves, it
is necessary to ensure that the new members support the plan.
6. As with every topic, the management (IESG and working group
chairs) need to clearly communicate the work plan to all
interested participants. Who is responsible for what? What is
in scope for a working group? Can additional items outside this
scope be taken elsewhere, and if so, where? When a working
group closes, where are remaining items and maintenance topics
expected to be handled?
The key tool for defining the scope is the working group
charter. When work is identified as cross-area, it is necessary
to to make this clear in the charter. The charter should also
provide guidance on the work scope and who is responsible for
what. This helps then later when it is necessary to assign area
advisors, get early cross-area review, and so on.
7. The best examples of successful cross-area work involve
combining two pieces of expertise, with both parties having an
incentive to complete the work.
8. One good model that has been used in the Internet Area employs a
protocol detail working group and a consumer working group.
This model has been used with work that touches upon the DHCP
protocol, for instance. There are always two working groups:
the protocol working group and the consumer working group. The
DHC WG is not chartered to develop any extensions except for
maintaining the DHCP infrastructure itself. Extensions for a
Arkko Expires August 11, 2013 [Page 9]
Internet-Draft Cross-Area Work February 2013
specific application purpose (such as delivering location
information) must be owned by some other working group that is
chartered to develop those applications (such as the GEOPRIV WG
in the Real-Time Applications Area). The role of this consumer
working group is to drive the development of the entire
application where a DHCP option may play a small role.
The role of the DHC WG is to ensure that the DHCP aspects of
these extensions are properly designed. It is often easy to see
how the DHCP experts are clearly better at designing the right
container and behavior model for the DHCP part, and how the
consumer working group experts clearly understand the semantics
and needs for the actual data much better.
Division of responsibilities in this manner is encouraged in
other situations as well.
9. Scheduling models for the IETF should take cross-area work into
account in a better way. Possible tools to improve this include
the ability to specify entire areas as conflicts in the meeting
request tool. One commonly occurring special case of such
conflicts is ADs from multiple areas that are interested in a
working group. However, it is perhaps more important to
consider the wider audiences, such as directorates.
10. In general, the ability to associate work with all the areas
that it relates to will be helpful not just for scheduling, but
also for participants following an area of work, review teams,
and so on.
6. Informative References
[RFC2026] Bradner, S., "The Internet Standards Process -- Revision
3", BCP 9, RFC 2026, October 1996.
Appendix A. Acknowledgments
The author would like to thank the IESG for inspiring discussions
around the IETF processes. In particular, Dan Romascanu, Adrian
Farrell, Russ Housley, Lars Eggert, David Harrington, Ron Bonica,
Ralph Droms, Brian Haberman, Robert Sparks, and Stewart Bryant have
shared their thoughts on this matter over the years. Nothing in this
draft should be interpreted as an IESG opinion, however, as the draft
is the author's opinion only.
The author would also like to thank Joel Halpern, Keith Moore, Paul
Arkko Expires August 11, 2013 [Page 10]
Internet-Draft Cross-Area Work February 2013
Hoffman, Samita Chakrabarti, Melinda Shore, Barry Leiba, JW Atwood,
Tom Petch, Wesley George, Thomas Narten, Tony Hansen, SM, and Dan
Wing for feedback.
Author's Address
Jari Arkko
Ericsson
Jorvas 02420
Finland
Email: jari.arkko@piuha.net
Arkko Expires August 11, 2013 [Page 11]
