Internet Engineering Task Force (IETF) Y. Sheffer

Internet Engineering Task Force (IETF) Y. Sheffer
Request for Comments: 7942 Intuit
BCP: 205 A. Farrel
Obsoletes: 6982 Juniper Networks
Category: Best Current Practice July 2016
ISSN: 2070-1721

Improving Awareness of Running Code: The Implementation Status Section

Abstract

This document describes a simple process that allows authors of
Internet-Drafts to record the status of known implementations by
including an Implementation Status section. This will allow
reviewers and working groups to assign due consideration to documents
that have the benefit of running code, which may serve as evidence of
valuable experimentation and feedback that have made the implemented
protocols more mature.

This process is not mandatory. Authors of Internet-Drafts are
encouraged to consider using the process for their documents, and
working groups are invited to think about applying the process to all
of their protocol specifications. This document obsoletes RFC 6982,
advancing it to a Best Current Practice.

Status of This Memo

This memo documents an Internet Best Current Practice.

This document is a product of the Internet Engineering Task Force
(IETF). It has been approved for publication by the Internet
Engineering Steering Group (IESG). Further information on BCPs is
available in Section 2 of RFC 7841.

Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
http://www.rfc-editor.org/info/rfc7942.

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Copyright Notice

Copyright (c) 2016 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.

Table of Contents

1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. The "Implementation Status" Section . . . . . . . . . . . . . 4
2.1. Introductory Text . . . . . . . . . . . . . . . . . . . . 5
3. Alternative Formats . . . . . . . . . . . . . . . . . . . . . 5
4. Benefits . . . . . . . . . . . . . . . . . . . . . . . . . . 6
5. Security Considerations . . . . . . . . . . . . . . . . . . . 7
6. Informative References . . . . . . . . . . . . . . . . . . . 7
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 8
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 8

1. Introduction

Most IETF participants are familiar with the saying "rough consensus
and running code" [Tao] and can identify with its pragmatic approach.
However, implementation is not a requirement for publication as an
RFC. There are many examples of Internet-Drafts containing protocol
specifications that have gone through to publication as Proposed
Standard RFCs without implementation. Some of them may never get
implemented.

Over time, a variety of policies have been applied within the IETF to
consider running code. In the Routing Area, it used to be a
requirement that one or more implementations must exist before an
Internet-Draft could be published as a Proposed Standard RFC
[RFC1264]. That RFC was later obsoleted and the requirement for
implementation was lifted, but each working group was given the
authority to impose its own implementation requirements [RFC4794] and
at least one working group, Inter-Domain Routing (IDR), continues to
require two independent implementations.

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The hypothesis behind the current document is that there are benefits
to the IETF standardization process of producing implementations of
protocol specifications before publication as RFCs. These benefits,
which include determining that the specification is comprehensible
and that there is sufficient interest to implement, are further
discussed in Section 4.

This document describes a simple mechanism that allows authors of
Internet-Drafts to record and publicize the status of known
implementations by including an Implementation Status section. The
document defines (quite informally) the contents of this section to
ensure that the relevant information is included. This will allow
reviewers and working groups to assign due consideration to documents
that have the benefit of running code, which may serve as evidence of
valuable experimentation and feedback that have made the implemented
protocols more mature.

It is up to the individual working groups to use this information as
they see fit, but one result might be the preferential treatment of
documents, resulting in them being processed more rapidly. We
recommend that the Implementation Status section should be removed
from Internet-Drafts before they are published as RFCs. As a result,
we do not envisage changes to this section after approval of the
document for publication, e.g., the RFC errata process does not
apply.

This process is not mandatory. Authors of Internet-Drafts are
encouraged to consider using the process for their documents, and
working groups are invited to think about applying the process to all
of their protocol specifications.

The scope of this process is all Internet-Drafts (I-Ds) that contain
implementable specifications, whether produced within IETF working
groups or outside working groups but intended for IETF consensus.
I-Ds published on the Independent Stream are explicitly out of scope.
It is expected that the greatest benefit will be seen with Standards
Track documents developed within working groups.

This process was initially proposed as an experiment in [RFC6982].
That document is now obsoleted, and the process advanced to Best
Current Practice.

Historically, there have been other ways for experience based on
protocol implementations to feed back into the IETF process. Many
"implementation reports" have been published, in some cases several
years after the protocol was originally published. Providing

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feedback to published protocols is a related goal, but different from
the current document's focus. Two notable examples of published
implementation reports are [RFC1369] and [RFC5080].

2. The "Implementation Status" Section

Each Internet-Draft may contain a section entitled "Implementation
Status". This section, if it appears, should be located just before
the "Security Considerations" section and contain, for each existing
implementation, some or all of the following:

- The organization responsible for the implementation, if any.

- The implementation's name and/or a link to a web page where the
implementation or a description of it can be found.

- A brief general description.

- The implementation's level of maturity: research, prototype,
alpha, beta, production, widely used, etc.

- Coverage: which parts of the protocol specification are
implemented.

- Version compatibility: what version/versions of the Internet-Draft
are known to be implemented.

- Licensing: the terms under which the implementation can be used.
For example: proprietary, royalty licensing, freely distributable
with acknowledgement (BSD style), freely distributable with
requirement to redistribute source (General Public License (GPL)
style), and other (specify).

- Implementation experience: any useful information the implementers
want to share with the community.

- Contact information: ideally a person's name and email address,
but possibly just a URL or mailing list.

- The date when information about this particular implementation was
last updated.

In addition, this section can contain information about the
interoperability of any or all of the implementations, including
references to test-case descriptions and interoperability reports,
when such exist.

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Working group chairs and area directors (ADs) are requested to ensure
that this section is not used as a marketing venue for specific
implementations.

Since this information is necessarily time dependent, it is
inappropriate for inclusion in a published RFC. The authors should
include a note to the RFC Editor requesting that the section be
removed before publication.

2.1. Introductory Text

The following boilerplate text is proposed to head the Implementation
Status section:

This section records the status of known implementations of the
protocol defined by this specification at the time of posting of
this Internet-Draft, and is based on a proposal described in
RFC 7942. The description of implementations in this section is
intended to assist the IETF in its decision processes in
progressing drafts to RFCs. Please note that the listing of any
individual implementation here does not imply endorsement by the
IETF. Furthermore, no effort has been spent to verify the
information presented here that was supplied by IETF contributors.
This is not intended as, and must not be construed to be, a
catalog of available implementations or their features. Readers
are advised to note that other implementations may exist.

According to RFC 7942, "this will allow reviewers and working
groups to assign due consideration to documents that have the
benefit of running code, which may serve as evidence of valuable
experimentation and feedback that have made the implemented
protocols more mature. It is up to the individual working groups
to use this information as they see fit".

Authors are requested to add a note to the RFC Editor at the top of
this section, advising the Editor to remove the entire section before
publication, as well as the reference to RFC 7942.

3. Alternative Formats

Sometimes it can be advantageous to publish the implementation status
separately from the base Internet-Draft, e.g., on the IETF wiki:

- When the Implementation Status section becomes too large to be
conveniently managed within the document.

- When a working group decides to have implementors, rather than
authors, keep the status of their implementations current.

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- When a working group already maintains an active wiki and prefers
to use it for this purpose.

- If the working group decides that the information is still
valuable (and needs to be kept current) after the I-D is published
as an RFC, and the Implementation Status section had been removed
from it.

It is highly desirable for all readers of the Internet-Draft to be
made aware of this information. Initially, this can be done by
replacing the Implementation Status section's contents with a URL
pointing to the wiki. Later, the IETF Tools may support this
functionality, e.g., by including such a link in the HTML file of the
document, similar to the IPR link.

If the implementation status is published separately from the I-D,
then this information needs to be openly available without requiring
authentication, registration, or access controls if it is to have any
useful effects.

4. Benefits

Publishing the information about implementations provides the working
group with several benefits:

- Working group members, chairs, and ADs may use the information
provided to help prioritize the progress of I-Ds, e.g., when there
are several competing proposals to solve a particular problem.

- Similarly, the information is useful when deciding whether the
document should be progressed on a different track (individual
submission, Experimental, etc.).

- Making this information public and an explicit part of WG
deliberations will motivate participants to implement protocol
proposals, which in turn helps in discovering protocol flaws at an
early stage.

- Other participants can use the software to evaluate the usefulness
of protocol features, its correctness (to some degree), and other
properties, such as resilience and scalability.

- WG members may choose to perform interoperability testing with
known implementations, especially when they are publicly
available.

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- In the case of open source, people may want to study the code to
better understand the protocol and its limitations, determine if
the implementation matches the protocol specification, and whether
the protocol specification has omissions or ambiguities.

- And lastly, some protocol features may be hard to understand, and
for such features, the mere assurance that they can be implemented
is beneficial. We note though that code should never be used in
lieu of a clear specification.

We do not specify here whether and to what degree working groups are
expected to prefer proposals that have "running code" associated with
them, over others that do not.

Working group chairs are invited to suggest this mechanism to
document editors in their working groups, and to draw the attention
of their working group participants to Implementation Status sections
where they exist.

5. Security Considerations

This is a process document; therefore, it does not have a direct
effect on the security of any particular IETF protocol. However,
better-reviewed protocols are likely to also be more secure.

6. Informative References

[RFC1264] Hinden, R., "Internet Engineering Task Force Internet
Routing Protocol Standardization Criteria", RFC 1264,
DOI 10.17487/RFC1264, October 1991,
<http://www.rfc-editor.org/info/rfc1264>.

[RFC1369] Kastenholz, F., "Implementation Notes and Experience for
the Internet Ethernet MIB", RFC 1369,
DOI 10.17487/RFC1369, October 1992,
<http://www.rfc-editor.org/info/rfc1369>.

[RFC4794] Fenner, B., "RFC 1264 Is Obsolete", RFC 4794,
DOI 10.17487/RFC4794, December 2006,
<http://www.rfc-editor.org/info/rfc4794>.

[RFC5080] Nelson, D. and A. DeKok, "Common Remote Authentication
Dial In User Service (RADIUS) Implementation Issues and
Suggested Fixes", RFC 5080, DOI 10.17487/RFC5080, December
2007, <http://www.rfc-editor.org/info/rfc5080>.

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[RFC6982] Sheffer, Y. and A. Farrel, "Improving Awareness of Running
Code: The Implementation Status Section", RFC 6982,
DOI 10.17487/RFC6982, July 2013,
<http://www.rfc-editor.org/info/rfc6982>.

[Tao] Hoffman, P., Ed., "The Tao of IETF: A Novice's Guide to
the Internet Engineering Task Force", 2012,
<http://www.ietf.org/tao.html>.

Acknowledgements

We would like to thank Stephen Farrell, who reawakened community
interest in this topic. Several reviewers provided important input,
including Loa Andersson, Dave Crocker, Ned Freed, Joel M. Halpern,
Christer Holmberg, Denis Ovsienko, and Curtis Villamizar.

This document was originally prepared using the lyx2rfc tool, and we
would like to thank Nico Williams, its author.

Authors' Addresses

Yaron Sheffer
Intuit

Email: [email protected]

Adrian Farrel
Juniper Networks

Email: [email protected]

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