INTERNET-DRAFT                                             Thomas Narten
<draft-narten-iana-considerations-rfc2434bis>    Harald Tveit Alvestrand
                                                           March 6, 2005

       Guidelines for Writing an IANA Considerations Section in RFCs


Status of this Memo

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   Many protocols make use of identifiers consisting of constants and
   other well-known values. Even after a protocol has been defined and
   deployment has begun, new values may need to be assigned (e.g., for a
   new option type in DHCP, or a new encryption or authentication
   transform for IPsec).  To ensure that such quantities have consistent
   values and interpretations in different implementations, their
   assignment must be administered by a central authority. For IETF
   protocols, that role is provided by the Internet Assigned Numbers
   Authority (IANA).

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   In order for the IANA to manage a given name space prudently, it
   needs guidelines describing the conditions under which new values can
   be assigned. If the IANA is expected to play a role in the management
   of a name space, the IANA must be given clear and concise
   instructions describing that role.  This document discusses issues
   that should be considered in formulating a policy for assigning
   values to a name space and provides guidelines to document authors on
   the specific text that must be included in documents that place
   demands on the IANA.

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   Status of this Memo..........................................    1

   1.  Introduction.............................................    4

   2.  Why Management of a Name Space May be Necessary..........    4

   3.  Designated Experts.......................................    5
      3.1.  The Motivation For Designated Experts...............    6
      3.2.  The Role of the Designated Expert...................    7
      3.3.  Designated Expert Reviews...........................    7

   4.  Creating A Registry......................................    9
      4.1.  Well-Known IANA Policy Definitions..................    9
      4.2.  What To Put In Documents That Create A Registry.....   11
      4.3.  Updating Guidelines In Existing Registries..........   13

   5.  Registering Values In An Existing Registry...............   13
      5.1.  What to Put In Documents When Registering Values....   13
      5.2.  Maintaining Registrations...........................   14
      5.3.  Overriding Registration Procedures..................   15

   6.  Miscellaneous Issues.....................................   16
      6.1.  When There Are No IANA Actions......................   16
      6.2.  Appeals.............................................   16
      6.3.  Namespaces Lacking Documented Guidance..............   16

   7.  Security Considerations..................................   17

   8.  Open Issues..............................................   17

   9.  Changes Relative to RFC 2434.............................   18
      9.1.  Changes Relative to -00.............................   18
      9.2.  Changes Relative to -02.............................   18

   10.  IANA Considerations.....................................   19

   11.  Acknowledgments.........................................   19

   12.  Normative References....................................   19

   13.  Informative References..................................   19

   14.  Authors' Addresses....................................   21

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1.  Introduction

   Many protocols make use of fields that contain constants and other
   well-known values (e.g., the Protocol field in the IP header [IP] or
   MIME types in mail messages [MIME-REG]). Even after a protocol has
   been defined and deployment has begun, new values may need to be
   assigned (e.g., a new option type in DHCP [DHCP] or a new encryption
   or authentication algorithm for IPsec [IPSEC]).  To ensure that such
   fields have consistent values and interpretations in different
   implementations, their assignment must be administered by a central
   authority. For IETF protocols, that role is provided by the Internet
   Assigned Numbers Authority (IANA) [IANA-MOU].

   In this document, we call the set of possible values for such a field
   a "name space"; its actual value may be a text string, a number or
   another kind of value. The assignment of a specific value to a name
   space is called an assigned number (or assigned value). Each
   assignment of a number in a name space is called a registration.

   In order for the IANA to manage a given name space prudently, it
   needs guidelines describing the conditions under which new values
   should be assigned. This document provides guidelines to authors on
   what sort of text should be added to their documents, and reviews
   issues that should be considered in formulating an appropriate policy
   for assigning numbers to name spaces.

   Not all name spaces require centralized administration.  In some
   cases, it is possible to delegate a name space in such a way that
   further assignments can be made independently and with no further
   (central) coordination. In the Domain Name System, for example, the
   IANA only deals with assignments at the higher-levels, while
   subdomains are administered by the organization to which the space
   has been delegated. As another example, Object Identifiers (OIDs) as
   defined by the ITU are also delegated [ASSIGNED].  When a name space
   can be delegated, the scope of IANA is limited to the parts of the
   namespace where IANA has authority.

   This document uses the terms 'MUST', 'SHOULD' and 'MAY', and their
   negatives, in the way described in RFC 2119 [KEYWORDS]. In this case,
   "the specification" as used by RFC 2119 refers to the processing of
   protocols being submitted to the IETF standards process.

2.  Why Management of a Name Space May be Necessary

   One issue to consider in managing a name space is its size. If the
   space is small and limited in size, assignments must be made
   carefully to prevent exhaustion of the space. If the space is

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   essentially unlimited, on the other hand, potential exhaustion will
   probably not be a practical concern at all.  Even when the space is
   essentially unlimited, however, it is usually desirable to have at
   least a minimal review prior to assignment in order to:

    - prevent the hoarding of or unnecessary wasting of a space. For
      example, if the space consists of text strings, it may be
      desirable to prevent entities from obtaining large sets of strings
      that correspond to the "best" names (e.g., existing company

    - provide a sanity check that the request actually makes sense and
      is necessary. Experience has shown that some level of minimal
      review from a subject matter expert is useful to prevent
      assignments in cases where the request is malformed or not
      actually needed (i.e., an existing assignment for an essentially
      equivalent service already exists).

   A second consideration is whether it makes sense to delegate the name
   space in some manner. This route should be pursued when appropriate,
   as it lessens the burden on the IANA for dealing with assignments.

   A third, and perhaps most important consideration, concerns potential
   impact on interoperability of unreviewed extensions. Proposed
   protocol extensions generally benefit from community review; indeed,
   review is often essential to prevent future interoperability
   problems. [VENDOR-EXT] discusses this topic in considerable detail.

   In some cases, the name space is essentially unlimited and there are
   no potential interoperability issues; in such cases assigned numbers
   can safely be given out to anyone. When no subjective review is
   needed, the IANA can make assignments directly, provided that the
   IANA is given specific instructions on what types of requests it
   should grant, and what information must be provided as part of the
   request for an assigned number.

   It should be noted that the IANA does not create or define assignment
   policy itself; rather, it carries out policies that have been defined
   by others, i.e., in RFCs.  IANA must be given a set of guidelines
   that allow it to make allocation decisions with minimal subjectivity
   and without requiring any technical expertise with respect to the
   protocols that make use of a registry.

3.  Designated Experts

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3.1.  The Motivation For Designated Experts

   In most cases, some review of prospective allocations is appropriate,
   and the question becomes who should perform the review and what is
   the purpose of the review.  In many cases, one might think that an
   IETF Working Group (WG) familiar with the name space at hand should
   be consulted. In practice, however, WGs eventually disband, so they
   cannot be considered a permanent evaluator. It is also possible for
   name spaces to be created through individual submission documents,
   for which no WG is ever formed.

   One way to ensure community review of prospective assignments is to
   have the requester submit a document for publication as an RFC. Such
   an action helps ensure that the specification is publicly and
   permanently available, and allows some review of the specification
   prior to publication and assignment of the requested code points.
   This is the preferred way of ensuring review, and is particularly
   important if any potential interoperability issues can arise. For
   example, many assignments are not just assignments, but also involve
   an element of protocol specification. A new option may define fields
   that need to be parsed and acted on, which (if specified poorly) may
   not fit cleanly with the architecture of other options or the base
   protocols on which they are built.

   In some cases, however, the burden of publishing an RFC in order to
   get an assignment is excessive. However, it is generally still useful
   (and sometimes necessary) to discuss proposed additions on a mailing
   list dedicated to the purpose (e.g., the for
   media types) or on a more general mailing list (e.g., that of a
   current or former IETF WG).  Such a mailing list provides a way for
   new registrations to be publicly reviewed prior to getting assigned,
   or to give advice for persons who want help in understanding what a
   proper registration should contain.

   While discussion on a mailing list can provide valuable technical
   feedback, opinions may vary and discussions may continue for some
   time without clear resolution.  In addition, the IANA cannot
   participate in all of these mailing lists and cannot determine if or
   when such discussions reach consensus.  Therefore, the IANA relies on
   a "designated expert" to advise it in assignment matters. The
   designated expert is a single individual who is responsible for
   carrying out an appropriate evaluation and returning a recommendation
   to IANA.

   It should be noted that a key motivation for having designated
   experts is for the IETF to provide IANA with a single-person subject
   matter expert to which it can delegate the evaluation process to,
   with that person informing IANA whether the assignment is to be made.

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   IANA effectively delegates evaluating the request to the IETF's
   designated expert.

3.2.  The Role of the Designated Expert

   The designated expert is responsible for initiating and coordinating
   as wide a review of an assignment request as appropriate to evaluate
   it properly. This may involve consultation with a set of technology
   experts, discussion on a public mailing list, or consultation with a
   working group (or its mailing list if the working group has
   disbanded), etc. Ideally, the designated expert follows specific
   review criteria as documented in a related document that describes
   management of the namespace. (See the IANA Considerations sections of
   [RFC3748,RFC3575,XXX] for examples that have been done for specific
   name spaces).

   Designated experts are expected to be able to defend their decisions
   to the IETF community and the evaluation process is not intended to
   be secretive or bestow unquestioned power on the expert. Experts are
   expected to apply any documented review or vetting procedures that
   may apply, or in the absence of documented criteria, follow
   generally-accepted norms, e.g., those in section 3.3.

   Section 5.2 discusses disputes and appeals in more detail.

   Designated experts are appointed by the IESG (e.g., upon
   recommendation by the relevant Area Director). They are typically
   named at the time a document that creates a new numbering space is
   approved by the IESG, but as experts originally appointed may later
   become unavailable, the IESG will appoint replacements if necessary.

   Since the designated experts are appointed by the IESG, they may be
   removed by the IESG.

3.3.  Designated Expert Reviews

   In the seven years since RFC 2434 was published and has been put to
   use, experience has led to the following observations:

    - a designated expert must respond in a timely fashion, normally
      within a week for simple requests to a few weeks for more complex
      ones. Unreasonable delays can cause significant problems, such as
      when products need code points to ship. This is not to say that
      all reviews can be completed under a firm deadline, but they must
      be started, and the requester and IANA should have some
      transparency into the process if an answer cannot be given

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    - if a designated expert does not respond to IANA's requests within
      a reasonable period of time, either with a response, or to explain
      that the requests are particularly complex, and if this is a
      recurring event, the IANA must raise the issue with the IESG.
      Because of the problems caused by delayed evaluations and
      assignments, the IESG should take appropriate actions, such as
      ensuring that the expert understands their responsibilities, or
      appointing a new expert.

    - The designated expert is not required to personally bear the
      burden of evaluating and deciding all requests, but acts as a sort
      of shepherd for the request, enlisting the help of others as
      appropriate. In the case that a request is denied, and rejecting
      the request is likely to be controversial, the expert should have
      the support of other subject matter experts for a particular
      decision. That is, the expert must be able to defend a decision to
      the community as a whole.

   In the case where a designated expert is used, but there are no
   specific documented criteria for performing an evaluation, the
   presumption should be that a code point should be granted, unless
   there is a compelling reason not to. Possible reasons include:

    - scarcity of codepoints, where the finite remaining codepoints
      should be prudently managed, or when a request for a large number
      of codepoints is made, when a single codepoint is the norm.

    - documentation is not of sufficient clarity to evaluate or ensure

    - the code point is needed for a protocol extension, but the
      extension is not consistent with the documented (or generally
      understood) architecture of the base protocol being extended, and
      would be harmful to the protocol if widely deployed. It is not the
      intent that "inconsistencies" refer to minor differences "of a
      personal preference nature;" instead, they refer to significant
      differences such as inconsistencies with the underlying security
      model, implying a change to the semantics of an existing message
      type or operation, requiring unwarranted changes in deployed
      systems (compared with alternate ways of achieving a similar
      result), etc.

    - the extension would cause problems with existing deployed systems.

    - the extension would conflict with one under active development by
      the IETF, and having both would harm rather than foster

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4.  Creating A Registry

   Creating a registry involves describing the name spaces to be created
   together with an initial set of assignments (if appropriate) and
   guidelines on how future assignments are to be made.

4.1.  Well-Known IANA Policy Definitions

   The following are some defined policies, some of which are in use
   today. These cover a range of typical policies that have been used to
   date to describe the procedure for assigning new values in a name
   space. It is not required that documents use these terms; the actual
   requirement is that the instructions to IANA are clear and
   unambiguous. However, it is preferable to use these terms where
   possible, since their meaning is widely understood.

      Private Use - For private or local use only, with the type and
             purpose defined by the local site. No attempt is made to
             prevent multiple sites from using the same value in
             different (and incompatible) ways. There is no need for
             IANA to review such assignments (since IANA does not record
             them) and assignments are not generally useful for broad

             Examples: Site-specific options in DHCP [DHCP] have
             significance only within a single site.  "X-foo:" header
             lines in email messages.

      Experimental Use - Similar to private or local use only, with the
             purpose being to facilitate experimentation. See
             [EXPERIMENTATION] for details.

      Hierarchical allocation - Delegated managers can assign values
             provided they have been given control over that part of the
             name space.  IANA controls the higher levels of the
             namespace according to one of the other policies.

             Examples: DNS names, Object Identifiers, IP addresses

      First Come First Served - Anyone can obtain an assigned number, so
             long as they provide a point of contact and a brief
             description of what the value would be used for together
             with any other required information that is specifically
             required to be provided by the name space in question.  For

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             numbers, the exact value is generally assigned by the IANA;
             with names, specific text strings are usually requested.

             Examples: vnd. (vendor assigned) MIME types [MIME-REG], TCP
             and UDP port numbers.

      Expert Review (or Designated Expert) - approval by a Designated
             Expert is required. The required documentation and review
             criteria to be used by the Designated Expert should be
             provided when defining the registry.

      Specification required - Values and their meaning must be
             documented in an RFC or other permanent and readily
             available public specification, in sufficient detail so
             that interoperability between independent implementations
             is possible. When used, Specification Required also implies
             useage of a Designated Expert, who will review the public
             specification and evaluate whether it is sufficiently clear
             to allow interoperable implementations.

             Examples: SCSP [SCSP]

      RFC Required - RFC publication (either as IETF Submission or as an
             RFC Editor submission [RFC3932]) suffices.

      IETF Review - (Formerly called "IETF Consensus" in [IANA-
             CONSIDERATIONS]) New values are assigned only through RFCs
             that have been shepherded through the IESG as AD-Sponsored
             IETF Documents [RFC3932,RFC3978]. The intention is that the
             document and proposed assignment will be reviewed by the
             IESG and appropriate IETF WGs (or experts, if suitable
             working groups no longer exist) to ensure that the proposed
             assignment will not negatively impact interoperability or
             otherwise extend IETF protocols in an inappropriate or
             damaging manner.

             To ensure adequate community review, such documents are
             shepherded through the IESG as AD-sponsored documents with
             an IETF Last Call.

             Examples: SMTP extensions [SMTP-EXT], BGP Subsequent
             Address Family Identifiers [BGP4-EXT].

      Standards Action - Values are assigned only for Standards Track
             RFCs approved by the IESG.

             Examples: MIME top level types [MIME-REG]

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      IESG Approval - New assignments may be approved by the IESG.
             Although there is no requirement that the request be
             documented in an RFC, the IESG has discretion to request
             documents or other supporting materials on a case-by-case

             IESG Approval is not intended to be used often or as a
             "common case;" indeed, it has seldom been used in practice
             during the period RFC 2434 was in effect. Rather, it is
             intended to be available in conjunction with other policies
             as a fall-back mechanism in the case where one of the other
             allowable approval mechanisms cannot be employed in a
             timely fashion or for some other compelling reason. IESG
             Approval is not intended to circumvent the public review
             processes implied by other policies that could have been
             employed for a particular assignment.

             The following guidelines are suggested for any evaluation
             under IESG Approval:

              - The IESG can (and should) reject a request if another
                path is available that is more appropriate and allows
                broader community review

              - before approving a request, the community should be
                consulted, via a "call for comments" that provides as
                much information as is reasonably possible about the

   It should be noted that it often makes sense to partition a name
   space into several categories, with assignments out of each category
   handled differently. For example, the DHCP option space [DHCP] is
   split into two parts. Option numbers in the range of 1-127 are
   globally unique and assigned according to the Specification Required
   policy described above, while options number 128-254 are "site
   specific", i.e., Private Use. Dividing the name space up makes it
   possible to have different policies in place for different ranges.

4.2.  What To Put In Documents That Create A Registry

   The previous sections presented some issues that should be considered
   in formulating a policy for assigning well-known numbers and other
   protocol constants. It is the Working Group and/or document author's
   job to formulate an appropriate policy and specify it in the
   appropriate document. In almost all cases, having an explicit "IANA
   Considerations" section is appropriate. The following subsections
   define what is needed for the different types of IANA actions.

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   Documents that create a new name space (or modify the definition of
   an existing space) and that expect the IANA to play a role in
   maintaining that space (e.g., serving as a repository for registered
   values) MUST provide clear instructions on details of the name space.
   In particular, instructions MUST include:

     1) The name of the registry being created and/or maintained. The
        name will appear on the IANA web page and will be referred to in
        future documents that need to allocate a value from the new
        space. The full name (and abbreviation, if appropriate) should
        be provided. Ideally, the chosen name will not be easily
        confusable with the name of another registry.

     2) What information must be provided as part of a request in order
        to assign a new value.

     3) The review process that will apply to all future requests for a
        value from the namespace.

        Note: When a Designated Expert is used, documents MUST NOT name
        the Designated Expert in the document itself; instead, the name
        should be relayed to the appropriate IESG Area Director at the
        time the document is sent to the IESG for approval.

        If the request should also be reviewed on a specific public
        mailing list (such as the for media types),
        that mailing address should be specified. Note, however, that
        use of a Designated Expert MUST also be specified (see Section

        If the IANA is expected to make assignments without requiring an
        outside review, sufficient guidance MUST be provided so that the
        requests can be evaluated with minimal subjectivity.

   When specifying the process for making future assignments, it is
   quite acceptable to pick one of the example policies listed in
   Section 4.1 and refer to it by name.  Indeed, this is the preferred
   mechanism in those cases where the sample policies provide the
   desired level of review. It is also acceptable to cite one of the
   above policies and include additional guidelines for what kind of
   considerations should be taken into account by the review process.
   For example, RADIUS [RFC3575] specifies the use of a Designated
   Expert, but includes specific additional criteria the Designated
   Expert should follow.

   For example, a document could say something like:

        This document defines a new DHCP option, entitled "FooBar" (see

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        Section y), assigned a value of TBD1 from the DCHP Option space
        [RFCXXX]. The FooBar option also contains an 8-bit FooType
        field, for which IANA is to create and maintain a registry
        entitled "FooType values". Initial values for the FooType
        registry are given below; future assignments are to be made
        through Expert Review [IANA-CONSIDERATIONS]. Assignments consist
        of a name and the value.

            Name        Value        Definition
            ----        -----        ----------
            Frobnitz    1           See Section y.1
            NitzFrob    2           See Section y.2

   For examples of documents that provide good and detailed guidance to
   the IANA on the issue of assigning numbers, consult [MIME-REG, MIME-
   LANG, RFC3757, RFC3749, RFC3575].

4.3.  Updating Guidelines In Existing Registries

   Updating the registration process for an existing name space is
   similar to that used when creating a new namespace. That is, a
   document is produced that makes reference to the existing namespace
   and then provides detailed management guidelines for each individual
   name space. Such documents are normally processed as BCPs [IETF-

   Example documents that updated the guidelines for managing (then)
   pre-existing registries include: [RFC2929,RFC3228,RFC3575].

5.  Registering Values In An Existing Registry

5.1.  What to Put In Documents When Registering Values

   Often, a document requests the assignment of a code point from an
   already existing name space (i.e., one created by a previously-pub-
   lished RFC). In such cases documents should make clear:

    - From what name space is a value is being requested? List the exact
      name space listed on the IANA web page (and RFC), and cite the RFC
      where the name space is defined. (Note: There is no need to men-
      tion what the allocation policy for new assignments is, as that
      should be clear from the references.)

    - For each value being requested, give it a unique name. When the
      value is numeric, use the notation: TBD1, TBD2, etc. Throughout

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      the document where an actual IANA-assigned value should be filled
      in, use the "TBDx" notation. This helps ensure that the final RFC
      has the correct assigned value inserted in in all of the relevant
      places where the value is expected to be listed in the final docu-
      ment. For values that are text strings, a specific name can be
      suggested: IANA will assign the name, unless it conflicts with a
      name already in use.

    - Normally, the values to be used are chosen by IANA; documents
      shouldn't pick values themselves. However, in some cases a value
      may have been used for testing or in early implementations. In
      such cases, it is acceptable to include text suggesting what spe-
      cific value should be used (together with the reason for the
      choice). For example, one might include the text "the value XXX is
      suggested as it is used in implementations". However, it should be
      noted that suggested values are just that; IANA will attempt to
      assign them, but may find that impossible, if the proposed number
      has already been assigned for some other use.

      For many registries, IANA also has a long-standing policy pro-
      hibiting assignment of names or codes on a vanity or organization
      name basis, e.g., codes are always assigned sequentially unless
      there is a strong reason for making an exception.  Nothing in this
      document is intended to change those policies or prevent their
      future application.

    - The IANA Considerations section should summarize all of the IANA
      actions, with pointers to the relevant sections elsewhere in the
      document as appropriate. When multiple values are requested, it is
      generally helpful to include a summary table.  It is also often
      useful for this table to be in the format of the registry data in
      the IANA site

   As an example, the following text could be used to request assignment
   of a DHCPv6 option number:

      IANA has assigned an option code value of TBD1 to the DNS Recur-
      sive Name Server option and an option code value of TBD2 to the
      Domain Search List option from the DHCP option code space defined
      in section 24.3 of RFC 3315.

5.2.  Maintaining Registrations

   Registrations are a request for an assigned number, including the
   related information needed to evaluate and document the request. Even
   after a number has been assigned, some types of registrations contain

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   additional information that may need to be updated over time. For
   example, MIME types, character sets, language tags, etc. typically
   include more information than just the registered value itself.
   Example information can include point of contact information,
   security issues, pointers to updates, literature references, etc.  In
   such cases, the document defining the namespace must clearly state
   who is responsible for maintaining and updating a registration. In
   different cases, it may be appropriate to specify one or more of the

      - Let the author update the registration, subject to the same
        constraints and review as with new registrations.

      - Allow some mechanism to attach comments to the registration, for
        cases where others have significant objections to claims in a
        registration, but the author does not agree to change the

      - Designate the IESG or another entity as having the right to
        change the registrant associated with a registration and any
        requirements or conditions on doing so. This is mainly to get
        around the problem when a registrant cannot be reached in order
        to make necessary updates.

5.3.  Overriding Registration Procedures

   Since RFC 2434 was published, experience has shown that the
   documented IANA considerations for individual protocols do not always
   adequately cover the reality on the ground. For example, many older
   routing protocols do not have documented, detailed IANA
   considerations. In addition, documented IANA considerations are
   sometimes found to be too stringent to allow even working group
   documents (for which there is strong consensus) to obtain code points
   from IANA in advance of actual RFC publication.  In other cases, the
   documented procedures are unclear or neglected to cover all the
   cases. In order to allow assignments in individual cases where there
   is strong IETF consensus that an allocation should go forward, but
   the documented procedures do not support such an assignment, the IESG
   is granted authority to approve assignments in such cases. The
   intention is not to overrule properly documented procedures, or to
   obviate the need for protocols to properly document their IANA
   Considerations. Instead, the intention is to permit assignments in
   individual cases where it is obvious that the assignment should just
   be made, but updating the IANA process just to assign a particular
   code point is viewed as too heavy a burden. In general, the IETF
   would like to see deficient IANA registration procedures for a
   namespace revised through the IETF standards process, but not at the

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   cost of unreasonable delay for needed assignments.

6.  Miscellaneous Issues

6.1.  When There Are No IANA Actions

   Before an Internet-Draft can be published as an RFC, IANA needs to
   know what actions (if any) it needs to perform. Experience has shown
   that it is not always immediately obvious whether a document has no
   IANA actions, without reviewing a document in some detail. In order
   to make it clear to IANA that it has no actions to perform (and that
   the author has consciously made such a determination!), such
   documents should include an IANA Considerations section that states:

      This document has no IANA Actions.

   This statement, or an equivalent form of words, must only be inserted
   after the WG or individual submitter has carefully verified it to be

   In some cases, the absence of IANA-assigned values may be considered
   valuable information for future readers; in other cases it may be
   considered of no value once the document has been approved, and may
   be removed before archival publication. This choice should be made
   clear in the draft, for example by including a sentence such as

        [RFC Editor: please remove this section prior to publication.]


        [RFC Editor: please do not remove this section.]

6.2.  Appeals

   Appeals on registration decisions made by the IANA can be appealed
   using the normal IETF appeals process as described in  Section 6.5 of
   [IETF-PROCESS]. Specifically, appeals should be directed to the IESG,
   followed (if necessary) by an appeal to the IAB, etc.

6.3.  Namespaces Lacking Documented Guidance

   For all existing RFCs that either explicitly or implicitly rely on
   the IANA to evaluate assignments without specifying a precise

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   evaluation policy, the IANA (in consultation with the IESG) will
   continue to decide what policy is appropriate. Changes to existing
   policies can always be initiated through the normal IETF consensus

   All future RFCs that either explicitly or implicitly rely on the IANA
   to register or otherwise manage assignments MUST provide guidelines
   for managing the name space.

7.  Security Considerations

   Information that creates or updates a registration needs to be
   authenticated and authorized.

   Information concerning possible security vulnerabilities of a
   protocol may change over time. Likewise, security vulnerabilities
   related to how an assigned number is used (e.g., if it identifies a
   protocol) may change as well. As new vulnerabilities are discovered,
   information about such vulnerabilities may need to be attached to
   existing registrations, so that users are not mislead as to the true
   security issues surrounding the use of a registered number.

   An analysis of security issues is required for all parameters (data
   types, operation codes, keywords, etc.) used in IETF protocols or
   registered by the IANA. All descriptions of security issues must be
   as accurate as possible regardless of level of registration.  In
   particular, a statement that there are "no security issues associated
   with this type" must not given when it would be more accurate to
   state that "the security issues associated with this type have not
   been assessed".

8.  Open Issues

    - It has been suggested that mailing lists associated with public
      reviews (e.g., ietf-types) should be hosted by IETF servers and
      should have public archives available. To what degree should we
      have requirements? Should we have a policy, and should it be
      documented here?

    - Added text to "Specification Required" stating that an Expert will
      be used to evaluate a spec for adequate "implementability". Is
      this reasonable? [IANA can't do the evaluation, as they lack the
      necessary time/expertise. So someone has to do it...]

    - It would be good to get feedback on whether the examples of "good

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      IANA Considerations" that are cited are actually good, or whether
      better ones are available.

9.  Changes Relative to RFC 2434

   Changes include:

    - Major reordering of text to group the "creation of registries"
      text in same section, etc.

    - Numerous editorial changes to improve readability.

    - Change "IETF Consensus" term to "IETF Review" and added more

    - Added "RFC Required" to list of defined policies.

    - Much more explicit directions and examples of "what to put in

    - "Specification Required" now implies use of Designated Expert to
      evaluate specs for sufficient clarity.

    - no doubt other things...

9.1.  Changes Relative to -00

   - Revised Section 5.3 to try and make it even more clear.

9.2.  Changes Relative to -02

      - Significantly changed the wording in Section 3. Main purpose is
         to make clear the Expert Reviewers are accountable to the com-
         munity, and to provide some guidance for review criteria in the
         default case.

      - removed wording: "By virtue of the IAB's role as overseer of
         IANA administration [RFC 1602], the IAB's decision is final
         [IETF-PROCESS]." This document now makes no changes to existing
         appeal mechanisms relative to RFC 2026.

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10.  IANA Considerations

   This document is all about IANA Considerations.

11.  Acknowledgments

   This document has benefited from specific feedback from Marcelo
   Bagnulo Braun, Brian Carpenter, Spencer Dawkins, John Klensin,
   Allison Mankin, Mark Townsley and Bert Wijnen.

   The original acknowledgements section in RFC 2434 was:

   Jon Postel and Joyce Reynolds provided a detailed explanation on what
   the IANA needs in order to manage assignments efficiently, and
   patiently provided comments on multiple versions of this document.
   Brian Carpenter provided helpful comments on earlier versions of the
   document. One paragraph in the Security Considerations section was
   borrowed from [MIME-REG].

12.  Normative References

13.  Informative References

   [ASSIGNED] Reynolds, J., and J. Postel, "Assigned Numbers", STD 2,
                    RFC 1700, October 1994.  See also:

   [BGP4-EXT] Bates. T., Chandra, R., Katz, D. and Y.  Rekhter,
                    "Multiprotocol Extensions for BGP-4", RFC 2283,
                    February 1998.

   [DHCP-OPTIONS] Alexander, S. and R. Droms, "DHCP Options and BOOTP
                    Vendor Extensions", RFC 2132, March 1997.

   [EXPERIMENTATION] "Assigning Experimental and Testing Numbers
                    Considered Useful". T.  Narten, RFC 3692, January

   [IANA-CONSIDERATIONS] Alvestrand, H. and T. Narten, "Guidelines for
                    Writing an IANA Considerations Section in RFCs", BCP
                    26, RFC 2434, October 1998.

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   [IANA-MOU] Memorandum of Understanding Concerning the Technical Work
                    of the Internet Assigned Numbers Authority. B.
                    Carpenter, F. Baker, M.  Roberts, RFC 2860, June

   [IETF-PROCESS] Bradner, S., "The Internet Standards Process --
                    Revision 3", BCP 9, RFC 2026, October 1996.

   [IP] Postel, J., "Internet Protocol", STD 5, RFC 791, September 1981.

   [IPSEC] Atkinson, R., "Security Architecture for the Internet
                    Protocol", RFC 1825, August 1995.

   [KEYWORDS] Bradner, S., "Key words for use in RFCs to Indicate
                    Requirement Levels", BCP 14, RFC 2119, March 1997.

   [MIME-LANG] Freed, N. and K. Moore, "MIME Parameter Value and Encoded
                    Word Extensions: Character Sets, Languages, and
                    Continuations", RFC 2184, August 1997.

   [MIME-REG] Freed, N., Klensin, J. and J. Postel, "Multipurpose
                    Internet Mail Extension (MIME) Part Four:
                    Registration Procedures", RFC 2048, November 1996.

   [SCSP] Luciani, J., Armitage, G. and J. Halpern, "Server Cache
                    Synchronization Protocol (SCSP)", RFC 2334, April

   [SMTP-EXT] Klensin, J., Freed, N., Rose, M., Stefferud, E.  and D.
                    Crocker, "SMTP Service Extensions", RFC 1869,
                    November 1995.

   [VENDOR-EXT] "Considerations on the Extensibility of IETF protocols",

   [RFC2929] Domain Name System (DNS) IANA Considerations. D. Eastlake
                    3rd, E.  Brunner-Williams, B. Manning. September

   [RFC3228] IANA Considerations for IPv4 Internet Group Management
                    Protocol (IGMP). B. Fenner. February 2002.

   [RFC3575] IANA Considerations for RADIUS (Remote Authentication Dial
                    In User Service). B. Aboba. RFC 3575, July 2003.

   [RFC3978] IETF Rights in Contributions. S. Bradner, Ed.. March 2005.

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   [RFC3575] IANA Considerations for RADIUS (Remote Authentication Dial
                    In User Service). B. Aboba. July 2003.

   [RFC3748] Extensible Authentication Protocol (EAP). B. Aboba, L.
                    Blunk, J.  Vollbrecht, J. Carlson, H. Levkowetz,
                    Ed.. June 2004.

   [RFC3932] The IESG and RFC Editor Documents: Procedures. H.
                    Alvestrand.  October 2004.

14.  Authors' Addresses

   Thomas Narten
   IBM Corporation
   3039 Cornwallis Ave.
   PO Box 12195 - BRQA/502
   Research Triangle Park, NC 27709-2195

   Phone: 919-254-7798

   Harald Tveit Alvestrand
   Cisco Systems
   5245 Arboretum Dr
   Los Altos, CA


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