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9. Miscellaneous Issues

This section addresses various miscellaneous issues that arise in the management of IANA registries.

9.1. 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 the 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, after the authors confirm that this is the case, include an IANA Considerations section that states:

This document has no IANA actions.

IANA prefers that these "empty" IANA Considerations sections be left in the document for the record: it makes it clear later on that the document explicitly said that no IANA actions were needed (and that it wasn't just omitted). This is a change from the prior practice of requesting that such sections be removed by the RFC Editor, and authors are asked to accommodate this change.

9.2. Namespaces Lacking Documented Guidance​

For all existing RFCs that either explicitly or implicitly rely on IANA to make assignments without specifying a precise assignment policy, IANA will work with the IESG to decide what policy is appropriate. Changes to existing policies can always be initiated through the normal IETF consensus process, or through the IESG when appropriate.

All future RFCs that either explicitly or implicitly rely on IANA to register or otherwise administer namespace assignments must provide guidelines for administration of the namespace.

9.3. After-the-Fact Registrations​

Occasionally, the IETF becomes aware that an unassigned value from a namespace is in use on the Internet or that an assigned value is being used for a different purpose than it was registered for. The IETF does not condone such misuse; procedures of the type described in this document need to be applied to such cases, and it might not always be possible to formally assign the desired value. In the absence of specifications to the contrary, values may only be reassigned for a different purpose with the consent of the original assignee (when possible) and with due consideration of the impact of such a reassignment. In cases of likely controversy, consultation with the IESG is advised.

This is part of the reason for the advice in Section 3.1 about using placeholder values, such as "TBD1", during document development: problems are often caused by the open use of unregistered values after results from well-meant, early implementations, where the implementations retained the use of developmental code points that never proceeded to a final IANA assignment.

9.4. Reclaiming Assigned Values​

Reclaiming previously assigned values for reuse is tricky, because doing so can lead to interoperability problems with deployed systems still using the assigned values. Moreover, it can be extremely difficult to determine the extent of deployment of systems making use of a particular value. However, in cases where the namespace is running out of unassigned values and additional ones are needed, it may be desirable to attempt to reclaim unused values. When reclaiming unused values, the following (at a minimum) should be considered:

  • Attempts should be made to contact the original party to which a value is assigned, to determine if the value was ever used, and if so, the extent of deployment. (In some cases, products were never shipped or have long ceased being used. In other cases, it may be known that a value was never actually used at all.)

  • Reassignments should not normally be made without the concurrence of the original requester. Reclamation under such conditions should only take place where there is strong evidence that a value is not widely used, and the need to reclaim the value outweighs the cost of a hostile reclamation. IESG Approval is needed in this case.

  • It may be appropriate to write up the proposed action and solicit comments from relevant user communities. In some cases, it may be appropriate to write an RFC that goes through a formal IETF process (including IETF Last Call) as was done when DHCP reclaimed some of its "Private Use" options [RFC3942].

  • It may be useful to differentiate between revocation, release, and transfer. Revocation occurs when IANA removes an assignment, release occurs when the assignee initiates that removal, and transfer occurs when either revocation or release is coupled with immediate reassignment. It may be useful to specify procedures for each of these or to explicitly prohibit combinations that are not desired.

9.5. Contact Person vs Assignee or Owner​

Many registries include designation of a technical or administrative contact associated with each entry. Often, this is recorded as contact information for an individual. It is unclear, though, what role the individual has with respect to the registration: is this item registered on behalf of the individual, the company the individual worked for, or perhaps another organization the individual was acting for?

This matters because some time later, when the individual has changed jobs or roles, and perhaps can no longer be contacted, someone might want to update the registration. IANA has no way to know what company, organization, or individual should be allowed to take the registration over. For registrations rooted in RFCs, the stream owner (such as the IESG or the IAB) can make an overriding decision. But in other cases, there is no recourse.

Registries can include, in addition to a "Contact" field, an "Assignee" or "Owner" field (also referred to as "Change Controller") that can be used to address this situation, giving IANA clear guidance as to the actual owner of the registration. This is strongly advised, especially for registries that do not require RFCs to manage their information (e.g., registries with policies such as First Come First Served (Section 4.4), Expert Review (Section 4.5), and Specification Required (Section 4.6)). Alternatively, organizations can put an organizational role into the "Contact" field in order to make their ownership clear.

9.6. Closing or Obsoleting a Registry/Registrations​

Sometimes there is a request to "close" a registry to further registrations. When a registry is closed, no further registrations will be accepted. The information in the registry will still be valid and registrations already in the registry can still be updated.

A closed registry can also be marked as "obsolete", as an indication that the information in the registry is no longer in current use.

Specific entries in a registry can be marked as "obsolete" (no longer in use) or "deprecated" (use is not recommended).

Such changes to registries and registered values are subject to normal change controls (see Section 2.3). Any closure, obsolescence, or deprecation serves to annotate the registry involved; the information in the registry remains there for informational and historic purposes.