Network Working Group S. Trowbridge
Request for Comments: 4053 Lucent Technologies
BCP: 103 S. Bradner
Category: Best Current Practice Harvard University
Procedures for Handling Liaison Statements to and from the IETF
Status of This Memo
This document specifies an Internet Best Current Practices for the
Internet Community, and requests discussion and suggestions for
improvements. Distribution of this memo is unlimited.
Copyright (C) The Internet Society (2005).
This document describes the procedure for proper handling of incoming
liaison statements from other standards development organizations
(SDOs), consortia, and industry fora, and for generating liaison
statements to be transmitted from IETF to other SDOs, consortia and
industry fora. This procedure allows IETF to effectively collaborate
with other organizations in the international standards community.
The IETF expects that liaison statements might come from a variety of
organizations, and it may choose to respond to many of those. The
IETF is only obligated to respond if there is an agreed liaison
Table of Contents
1. Introduction ....................................................3
2. Liaison Statements and Their Handling ...........................3
2.1. Definitions ................................................3
2.2. Liaison Statements .........................................4
2.2.1. Contents of a Liaison Statement .....................4
184.108.40.206. Envelope Information .......................4
220.127.116.11. Liaison Content ............................5
2.3. Addressee Responsibilities .................................6
2.4. Lifetime of a Liaison Statement ............................7
3. Tools for Handling Liaison Statements ...........................7
3.1. Liaison Statements from Other SDOs, Consortia, and
Fora to IETF ...............................................7
3.1.1. Liaison Statement Submission ........................8
3.1.2. Mechanism for Displaying Liaison Statements .........9
3.2. Communicating IETF Information to Other SDOs,
Consortia, and Fora ........................................9
3.2.1. Spontaneously Generating Liaison Statements
to Other ............................................9
18.104.22.168. Transmitting IETF Documents to
Other Organizations .......................10
22.214.171.124. Requests for Information ..................10
126.96.36.199. Requesting Comments on Work in Progress ...11
188.8.131.52. Requests for Other Actions
(Besides Comments on IETF Drafts) .........11
3.2.2. Responding to Incoming Liaison Statements ..........11
184.108.40.206. Responding to Requests for Information ....11
220.127.116.11. Responding to Requests for Comments .......12
18.104.22.168. Responding to Request for Action ..........12
22.214.171.124. Generating Liaison Statements .............13
4. Security Considerations ........................................13
5. Acknowledgements ...............................................14
A. Implementation Road map ........................................15
A.1. Phase I: Initial Implementation ...........................15
A.1.1. Displays .........................................15
A.1.2. Actions on Submission ............................16
B. Phase II: Additional Instrumentation and Responses to
Usage Experience ...............................................17
Normative References ..............................................17
This document describes the procedure for generating and handling
liaison statements between the IETF and other SDOs, so that IETF can
effectively collaborate with other organizations in the international
standards community. These liaison statements are primarily
exchanged between IETF and organizations with whom the IAB has
created a liaison relationship (see [RFC4052]), although other
organizations are not precluded. The procedures described in this
document encompass all liaisons statements received from SDOs,
whether or not a formal liaison arrangement is in place between the
SDO and the IETF. The IETF is not obligated to respond to the
liaison statement where there is no formal liaison arrangement.
The implementation of the procedure and supporting tools is occurring
in a minimum of three phases. The initial phase has been the
development of a prototype (in the best tradition of "rough consensus
and running code"), by Sunny Lee of Foretec, in parallel with the
development of this specification. The second phase is the
conversion of that prototype to an operational tool. This
operational tool lacks an automated tracking tool; rather, the
liaison manager implements it in his or her own way. The third phase
will include that tracking tool.
The specific supporting tools and their functionality described in
this document are one possible way of providing automated support for
the processes described in this document. Because specific tools and
their functionality will change over time, the descriptions in this
document are to be considered examples only and are not a normative
part of this specification.
2. Liaison Statements and Their Handling
Let us first define what a liaison statement is (and is not), and set
reasonable expectations. The expectations in this section are
normative for a liaison statement sent by any SDO to the IETF.
For purposes of clarity, we use the following definitions:
Addressee: The Working Group(s) (WG) or other party(s) in the IETF to
whom a liaison statement is addressed.
Assignee: The person responsible to act on a liaison statement,
initially either the person to whom it was addressed or the chair
of the group to which it was addressed. The task may be
reassigned to another person in the same or a different group as
Liaison manager: A person designated to act as a manager of the
relationship between the IETF and a peer organization to ensure
that communication is maintained, is productive, and is timely, as
defined by sections 2.2 and 3 in [RFC4052].
Liaison statement: A letter as described in this document, exchanged
2.2. Liaison Statements
A Liaison Statement is a business letter sent by one standards
organization to another. These organizations may be at any level
(WG, Area, etc.) Generally, the sender and receiver are peer
organizations. A liaison statement may have any purpose, but
generally the purpose is to solicit information, make a comment or
request an action.
2.2.1. Contents of a Liaison Statement
Liaison statements may be very formal or informal, depending on the
rules of the body generating them. Any liaison statement, however,
will always contain certain information, much as an business letter
does. This information will include the following:
126.96.36.199. Envelope Information
The following fields detail properties of the liaison statement.
The statement will indicate from what body it originates; for
example, it may be from, an IETF WG or Area, an ITU-T Study Group,
Working Party, or Question, etc. In this document, this body is the
The statement will indicate to which body it is. In this document,
this body is the "addressee".
The statement will contain a short (usually single line) statement of
its context and content.
188.8.131.52.4. Response Contact:
The sender will indicate the electronic mail address to which any
response should be sent.
184.108.40.206.5. Technical Contact:
The sender will indicate one or more electronic mail addresses
(persons or lists) that may be contacted for clarification of the
A liaison statement generally has one of three purposes and will
clearly state its purpose using one of the following labels:
For Information: The liaison statement is to inform the addressee of
something, and expects no response.
For Comment: The liaison statement requests commentary from the
addressee, usually within a stated time frame.
For Action: The liaison statement requests that the addressee do
something on the sender's behalf, usually within a stated time
In Response: The liaison statement includes a response to a liaison
statement from the peer organization on one or more of its
documents and expects no further response.
Liaison statements that request comment or action will indicate when
the comment or action is required. If the addressee cannot
accomplish the request within the stated period, courtesy calls for a
response offering a more doable deadline or an alternative course of
220.127.116.11. Liaison Content
The following fields are the substance of the liaison statement.
IETF participants use a wide variety of systems, thus document
formats that are not universally readable are problematic. As a
result, documents enclosed with the body or attachments should be in
PDF, W3C HTML (without proprietary extensions), or ASCII text format.
If they were originally in a proprietary format such as Microsoft
Word, the file may be sent, but should be accompanied by a generally
As with any business letter, the liaison statement contains
appropriate content explaining the issues or questions at hand.
Attachments, if enclosed, may be in the form of documents sent with
the liaison statement or may be URLs to similar documents including
2.3. Addressee Responsibilities
The responsibilities of the addressee of a liaison statement are the
same as the responsibilities of any business letter. A liaison
statement calls for appropriate consideration of its contents, and if
a reply is requested and an appropriate relationship exists, a
courteous authoritative reply within the expected time frame. The
reply may be that the information was useful or not useful, that the
requested action has been accomplished, it will be accomplished by a
specified date, it will not be done for a specific reason, an answer
to a question posed, or any other appropriate reply.
A liaison statement, like any other temporary document, must be
considered for its relevance, importance, and urgency.
One hopes that a liaison statement will be sent to the right
organization, but this cannot be assured. An SDO might send a
liaison statement to a specific IETF Area whose Area Director (AD)
deems it better handled by one of the WGs, or it might be sent to one
WG when it should have gone to another. If a liaison statement
arrives that appears misdirected, the assignee should promptly ask
the liaison manager to redirect it appropriately. In some cases, a
liaison statement may require consideration by multiple groups within
the IETF; in such cases, one assignee takes the lead and
responsibility for developing a response.
Liaison Statements are always important to the body that sent them.
Having arrived at the appropriate body, the liaison statement may be
more or less important to the addressee depending on its contents and
the expertise of the sender. If the liaison statement seeks to
influence the direction of a WG's development, it should receive the
same consideration that any temporary document receives. The WG
chair may request the sender's contacts to make their case to the
IETF WG in the same manner that an author of an internet draft makes
his or her case.
The urgency of a liaison statement is usually reflected in its
deadline. A liaison statement for informational purposes may have no
deadline; in such a case, a courteous "thank you" liaison statement
is necessary to inform the sender that the liaison statement was
received. The WG may then inform itself of the contents and close
the document. A liaison statement specifying a deadline, however,
gives the addressee a finite opportunity to influence the activity of
another body; if it fails to react in a timely fashion, it may miss
2.4. Lifetime of a Liaison Statement
A liaison statement is a temporary document, much like an internet
draft. If it affects IETF output, the normal expectation is that the
resulting RFC will contain relevant information that remains
pertinent. Retaining liaison statements that have been completely
dealt with mostly serves to hide new ones and create the appearance
of not dealing with them.
However, unlike an internet draft, liaison statements are often the
only record the IETF has of the communication with the peer SDO. As
such, some liaison statements are referred to for relatively long
periods of time.
As a result, the IETF will archive liaison statements that have been
fully dealt with, along with any attachments that may have been
relevant, but do so in a manner obviously distinct from current
3. Tools for Handling Liaison Statements
Some tools have been developed for the IETF. Development is expected
to continue. This section describes the basic tool and its intended
3.1. Liaison Statements from Other SDOs, Consortia, and Fora to IETF
The process of handling a liaison statement is more weighty than
handling a business letter because it is important to a relationship
with another SDO established by the IAB. To manage liaison
statements, the IETF will offer three electronically accessible
facilities: a form for submission of liaison statements, a mechanism
organizing their contents and making them accessible, and a tracking
system. Initially, the tracking system will be a manual procedure
used by the liaison manager; in the future, this should be automated.
3.1.1. Liaison Statement Submission
The IETF Secretariat will provide an electronic method for submission
of liaison statements.
The liaison statement submission mechanism is a form that requests
the information listed in Section 2.2.1 from the user.
Submission of that information results in the following actions:
o creation of a display mechanism containing the envelope data in
Section 18.104.22.168 and URLs pointing to the items from
Section 22.214.171.124, an indication whether the liaison statement has
been replied to, and if so, on what date,
o the addition of a URL to the "outstanding liaison statements"
o when an automated tracking system has been implemented, a tickler/
status entry in the tracking system, assigned to the relevant
chair or AD,
o an email to the assignee copying
* the liaison statement's technical contacts
* The supervisor of the assignee (if it is to a WG, the relevant
ADs; if to an AD, the IETF Chair),
* The liaison manager for the sending SDO,
* an alias associated with the assignee (WG/BOF or other open
mailing list, Area Directorate, IESG, IAB, etc.)
This email should contain the URL to the liaison statement
mechanism, text indicating that the liaison statement has arrived,
requests appropriate consideration, and if a deadline is
specified, a reply by the deadline.
The assignee has the capability of interacting with the liaison
manager and the tracking system (once implemented), including
replying, changing dates, reassignment, closing the liaison statement
The liaison manager or tracking system's "tickle" function
periodically reminds the assignee by email that the liaison statement
has not yet been closed. This tickle email copies all of the above
except the associated mailing alias.
3.1.2. Mechanism for Displaying Liaison Statements
The IETF site contains a section for current liaison statement
activity. This consists of:
o A submission mechanism,
o A status/management mechanism for each active or recently closed
liaison statement, and zero or more associated files.
The status/management mechanism contains a simple frame, showing the
title of the liaison statement, the URL for its mechanism, and the
organizations it is from and to.
The display for liaison statement itself contains:
o the liaison statement envelope information (Section 2.2.1),
o direct content (Section 2.2.1),
o URLs for the various associated files
o current status of the liaison statement: to whom it is assigned,
its due date, and its status,
o pointer to the liaison manager and tracking system entry for the
o reply-generation mechanism (see Section 126.96.36.199)
3.2. Communicating IETF Information to Other SDOs, Consortia, and Fora
This includes liaison statements sent in reply to liaison statements
sent by other bodies, and liaison statements being originated by the
3.2.1. Spontaneously Generating Liaison Statements to Other
Liaison Statements can be generated at a WG, Area, or IETF level to
another organization. The respective (co)chair(s) are responsible
for judging the degree of consensus for sending the particular
liaison statement and deciding the content. The amount of consensus
required to send a liaison statement varies greatly depending on its
content. This section gives some rough guidance about how much
consensus should be sought before sending a liaison statement to
188.8.131.52. Transmitting IETF Documents to Other Organizations
The simplest case of approving sending of a liaison statement from
IETF is when the information being transmitted consists of an IETF
document that has some level of agreement within the IETF. The
process that the document has already gone through to achieve its
current status assures the necessary level of consensus. Any
Standards Track RFC (Draft Standard, Proposed Standard, Internet
Standard, BCP), and any WG document expected to be placed on the
standards track, may be transmitted without concern.
Informational documents may also be exchanged readily when they
represent a WG position or consensus, such as a requirements or
In all cases, the document status must be appropriately noted. In
the case of a WG Internet Draft, it must be clear that the existence
of the draft only indicates that the WG has accepted the work item
and, as the standard disclaimer says, the actual content can be
treated as nothing more than Work in Progress.
Individually submitted Internet Drafts, Experimental or Historical
RFCs, and non-WG informational documents should not be transmitted
without developing further consensus within the relevant group, as
these documents cannot be truthfully represented as any kind of IETF
184.108.40.206. Requests for Information
Another type of liaison statement that can be generated without the
need for extensive consensus building on the email list is a request
for information. The (co)chairs(s) can generate such a liaison
statement when they recognize, from the activities of the group, that
some additional information is helpful, for example, to resolve an
impasse (i.e., don't waste time arguing over what the real meaning or
intent of another SDOs document is, just ask the other SDO and base
further work on the "official" answer).
Other requests for information may request access to certain
documents of other organizations that are not publicly available.
220.127.116.11. Requesting Comments on Work in Progress
There may be cases when one feels that a document under development
in the IETF may benefit from the input of experts in another relevant
SDO, consortium, or forum. Generally, this is done before the text
is "fully cooked" so that input from experts in another organization
can be included in the final result. Comments would generally be
solicited for a standards track WG Internet Draft and some level of
consensus should be reached on the WG or other open mailing list that
it is appropriate to ask another organization for comments on an IETF
18.104.22.168. Requests for Other Actions (Besides Comments on IETF Drafts)
There are many other kinds of actions that might reasonably be
requested of another organization:
o In the case of overlapping or related work in another
organization, a request could be made that the other organization
change something to align with the IETF work.
o A request could be made for another organization to start a new
work item (on behalf of IETF).
o A request could be made for another organization to stop a work
item (presumably because it overlaps or conflicts with other work
in the IETF).
These kinds of requests are quite serious. They can certainly be
made when appropriate, but should only be made when there is the
clearest possible consensus within the particular WG, Area, or within
the IETF at large.
3.2.2. Responding to Incoming Liaison Statements
Any incoming liaison statement that indicates that it is for
"Comment" or for "Action" requires a response by the deadline; other
liaison statements may also be replied to, although a reply is
generally optional. It is the responsibility of the (co)chair(s) of
the addressed organization to ensure that a response is generated by
22.214.171.124. Responding to Requests for Information
If another organization requests information that can be found in an
IETF document of the types indicated in Section 126.96.36.199, this can be
transmitted by the (co)chair(s) of the addressed group, indicating
the level of agreement for the relevant document.
188.8.131.52. Responding to Requests for Comments
If an incoming liaison statement requests comments on a document from
another organization, a discussion will occur on the mailing list
where participants can provide their comments.
If a clear consensus is evident from the pattern of comments made to
the mailing list, the (co)chair(s) can summarize the conclusions in a
reply liaison statement back to the originating organization.
If no clear consensus is evident from the pattern of comments on the
mailing list, or if there is no further discussion, a response is
still due to the originator. A summary of the email comments, or
lack of interest in the issue, should be created and sent to the
originator, and represented as "collected comments" rather than a
consensus of the IETF group to which the liaison statement was
addressed. It is possible to send this kind of a reply even if some
of the comments are contradictory.
184.108.40.206. Responding to Request for Action
A request for Action is a fairly serious thing. Examples of the
kinds of actions that may be expected are:
o In the case of overlapping or related work in another
organization, another organization may request that the IETF align
its work with that of the other organization.
o A request could be made for IETF to undertake a new work item.
o A request could be made for IETF to stop a work item (presumably
because it overlaps or conflicts with other work in the
Consensus of the receiving group within IETF is clearly necessary to
fulfill the request. Fulfilling the request may require a great deal
of time and multiple steps, for example, if initiating or stopping a
work item requires a charter change.
There is, of course, no requirement that IETF perform the action that
was requested. But the request should always be taken seriously, and
a response is required. The originating organization must always be
informed of what, if anything, the IETF has decided to do in response
to the request. If the IETF decides not to honor the request, or to
honor it with modifications, the response should include the reasons
and, if applicable, the alternate course of action.
For tasks that require a great deal of time, it may be necessary that
several liaison statements be sent back to the originating
organization to report the status of the work and the anticipated
completion time. The first of these liaison statements must be
generated by the deadline indicated in the incoming liaison
220.127.116.11. Generating Liaison Statements
IETF participants, usually WG chairs, ADs, or other officials, need
to be able to send liaison statements to other SDOs. The mechanism
described in Section 3.1.2, listing appropriate contacts in other
SDOs with which the IAB has established liaison relationships,
provides that capability.
As a convenience, the liaison statement page described in
Section 3.1.2 may be used to generate a reply. If a person (usually
a WG chair or an AD) selects "reply", a new liaison statement page is
generated from the existing one, reversing the addressing
information. IETF documents should be referenced by URL, such as
The process of generating and approving transmission of liaison
statements is a matter of IETF process and is specified in [RFC4052].
4. Security Considerations
One of the key considerations in developing this process has been the
possibility of a denial of service attack on the IETF and its
processes. Historically, the IETF has not always handled liaison
statements effectively, resulting in people working in other
organizations becoming frustrated with it. Various organizations
have also used the liaison statement process to impose deadlines on
IETF activities, which has been frustrating for all concerned - the
IETF because it does not accept such deadlines, and other
organizations because they feel ignored.
For this reason the submission process is automated. While the IETF
cannot rate-limit the submitters, it can manage its internal
This issue is exacerbated by the lack of any authentication on the
part of the submitter. However, the IAB considers it important to be
able to accept liaison statements whether or not a liaison
relationship exists, so authentication of submitters is not an
This text has been prompted by discussions with numerous individuals
within IETF and other SDOs and fora, including Gary Fishman and Bert
Wijnen. It has been developed in cooperation with [RFC4052], which
is to say with the express cooperation of the chair of the IAB,
Leslie Daigle. Personal experiences and some "miscues" in
coordinating work across ITU-T Study Group 15 and the IETF Sub-IP
Area have also motivated this work. Some drafts addressing
individual problems (for example, RFC 3427) make it clear that a more
general, consistent solution is needed for dealing with outside
organizations. Certain ideas have been borrowed from these texts.
Barbara Fuller, Sunny Lee, and Michael Lee developed a prototype and
commented in detail on the document. Their inputs directly resulted
in the appendices describing the implementation road map.
Appendix A. Implementation Road Map
This section documents the development program as of the time of the
writing of this document. It is not normative.
A.1. Phase I: Initial Implementation
The descriptions of the required displays in Section 3.1.1 and
Section 3.1.2 call for two sets of displays: one for the public (for
viewing liaison statements), and one for submitters (for managing
Displays for public view of liaison statements include:
o A Liaison Statements Web page that lists all incoming and outgoing
liaison statements (specific fields TBD). The title of each
liaison statement is a link to the details page for that liaison
o A detail page for each liaison statement that contains:
* All of the information specified in the subsections of
* Links to all attachments that accompanied the liaison statement
or to documents that are mentioned in the statement but were
not provided as part of the submission.
* Links to all related liaison statements (e.g., replies).
Displays for submitting and managing liaison statements include:
o A summary page that offers mechanisms for:
* Creating and submitting a new liaison statement.
* Editing a liaison statement that the user has previously
created and submitted.
* Acting on a liaison statement that has been assigned to the
o A template for creating and submitting a liaison statement. This
template allows the user to enter the information specified in
Section 2.2.1. The user is able to access the template at any
time (from a list of liaison statements that the user has
previously created and submitted), and update and resubmit the
o A detail page for managing a liaison statement assigned to the
user. This page is similar to the details page available to the
public. However, it also includes:
* A mechanism for replying to the liaison statement (initial
* A link to a liaison statement tracking mechanism (future
A.1.2. Actions on Submission
Submission of a liaison statement results in the following actions:
o The information is uploaded to the database.
o An e-mail message with the content specified in Section 3.1.1 is
sent to the addressee with copies to the addresses specified in
Section 4.1, and to the Secretariat (as specified in [RFC4052]).
o The liaison statement is added to the list on the Liaison
Statements Web page.
o Two detail pages are created for the liaison statement: one for
the public (to view the liaison statement), and one for the sender
and the assignee (to manage the liaison statement).
As specified in Section 18.104.22.168, when a user selects reply on the
details page of a liaison statement, a template for creating and
submitting a new liaison statement is generated from the existing one
that copies "From" to "To" and specifies the respondent as the
individual the response is coming "From". Submission of this reply
liaison statement results in the same set of actions as submission of
any new liaison statement. In addition, a link to the details page
of this liaison statement is added to the list of related liaison
statements on the details pages (both public and management) of the
original liaison statement (i.e., the one to which the user replied).
Appendix B. Phase II: Additional Instrumentation and Responses to Usage
This section is for information, and is not normative.
The intended features of the future liaison statement tracking system
are discussed in Section 3.1. They include mechanisms for:
o Designating an assignee; the assignee is initially a person
associated with the body (IAB, IESG, Area, WG, etc.) to which the
liaison statement is addressed, but may subsequently be changed by
an IETF participant.
o Indicating the status of the liaison statement (e.g., actions
required, actions taken, etc. Specific options TBD).
o Sending ticklers to the assignee when action is required (with
copies to whomever is appropriate).
o Changing the status of the liaison statement, the deadline, or
o Reassigning responsibility.
o Closing the liaison statement.
[RFC4052] Daigle, L., "IAB Processes for Management of Liaison
Relationships", RFC 4052, April 2005.
Stephen J. Trowbridge
1200 West 120th Avenue, Suite 232, Room 34Z07
Westminster, Colorado 80234-2795
Phone: +1 303 920 6545
Fax: +1 303 920 6553
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Cambridge, Massachusetts 02138
Phone: +1 617 495 3864
Fax: +1 617 492 8835
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Santa Barbara, California 93117
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