Network Working Group
Internet Engineering Task Force (IETF) D. Thaler
Internet-Draft
Request for Comments: 8892 Microsoft
Updates: 2863 (if approved) D. Romascanu
Intended status: Best Current Practice
Category: Standards Track Independent
Expires: July 19, 2020 January 16,
ISSN: 2070-1721 August 2020
Guidelines and Registration Procedures for Interface Types and Tunnel
Types
draft-thaler-iftype-reg-07
Abstract
This document provides guidelines and procedures for those who are
defining, registering, or evaluating definitions of new interface
types ("ifType" values) and tunnel types. The original definition of
the IANA interface type registry predated the use of IANA
Considerations sections and YANG modules, and so some confusion arose
over time. Tunnel types were added later, with the same requirements
and allocation policy as interface types. This document updates RFC
2863,
2863 and provides updated guidance for these registries.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents an Internet Standards Track document.
This document is a product of the Internet Engineering Task Force
(IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list It represents the consensus of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid the IETF community. It has
received public review and has been approved for a maximum publication by the
Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of six months RFC 7841.
Information about the current status of this document, any errata,
and how to provide feedback on it may be updated, replaced, or obsoleted by other documents obtained at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on July 19, 2020.
https://www.rfc-editor.org/info/rfc8892.
Copyright Notice
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document authors. All rights reserved.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Problems . . . . . . . . . . . . . . . . . . . . . . . . . . 3
4. Interface Sub-Layers Sub-layers and Sub-Types . . . . . . . . . . . . . 4 Sub-types
4.1. Alternate Values . . . . . . . . . . . . . . . . . . . . 5
5. Available Formats . . . . . . . . . . . . . . . . . . . . . . 6
6. Registration . . . . . . . . . . . . . . . . . . . . . . . . 6
6.1. Procedures . . . . . . . . . . . . . . . . . . . . . . . 7
6.2. Media-specific OID-subtree assignments . . . . . . . . . 8 Media-Specific OID-Subtree Assignments
6.3. Registration Template . . . . . . . . . . . . . . . . . . 8
6.3.1. ifType . . . . . . . . . . . . . . . . . . . . . . . 8
6.3.2. tunnelType . . . . . . . . . . . . . . . . . . . . . 9
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10
7.1. MIB and YANG Modules . . . . . . . . . . . . . . . . . . 11
7.2. Transmission Number Assignments . . . . . . . . . . . . . 12
8. Security Considerations . . . . . . . . . . . . . . . . . . . 12
9. References . . . . . . . . . . . . . . . . . . . . . . . . . 12
9.1. Normative References . . . . . . . . . . . . . . . . . . 12
9.2. Informative References . . . . . . . . . . . . . . . . . 13
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 15
1. Introduction
The IANA IfType-MIB, which contains the list of interface type
(ifType) values, was originally defined in [RFC1573] as a separate
MIB module together with the Interfaces Group MIB (IF-MIB) module.
The IF-MIB module was subsequently updated and is currently specified
in [RFC2863], but this the latest IF-MIB RFC no longer contains the IANA
IfType-MIB. Instead, the IANA IfType-MIB is maintained by IANA as a
separate module. Similarly, [RFC7224] created an initial IANA
Interface Type YANG Module, and the current version is maintained by
IANA.
The current IANA IfType registry is at [ifType-registry], with the
same values also appearing in both [yang-if-type] and the IANAifType
textual convention at [IANAifType-MIB].
Although the ifType registry was originally defined in a MIB module,
the assignment and use of interface type values are not tied to MIB
modules or any other management mechanism. An interface type value
can be used as the value of a data model object (MIB object, YANG
object, etc.), or as part of a unique identifier of a data model for a
given interface type (e.g., in an OID), or simply as a value exposed
by local APIs or UI UIs on a device.
The TUNNEL-MIB was defined in [RFC2667] (now obsoleted by [RFC4087]) [RFC4087]),
which created a tunnelType registry ([tunnelType-registry] and the
IANAtunnelType textual convention at [IANAifType-MIB]) [IANAifType-MIB]), and it
defined the assignment policy for tunnelType values to always be
identical to the policy for assigning ifType values.
2. Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
3. Problems
This document addresses the following issues:
1. As noted in Section 1, the original guidance was written with
wording specific to MIB modules, and accordingly modules; accordingly, some confusion has
resulted when using YANG modules. This document clarifies that
ifTypes and tunnelTypes are independent from the type of, or even
existence of, a data model.
2. The use of and requirements around sub-layers and sub-types were
not well understood, but good examples of both now exist. This
is discussed in Section 4.
3. Since the ifType "Interface Types (ifType)" and tunnelType "Tunnel Types
(tunnelType)" registries were originally defined, and are still
retrievable, in the format of MIB modules (in addition to other
formats), confusion arose when adding YANG modules as another format,
format as to whether each is a separate registry. This is
discussed in Section 5.
4. The registries are retrievable in the format of MIB and YANG
modules, but there was previously no process guidance written to
check that those formats were syntactically correct as updates
were made, which led to the registry having syntax errors that
broke tools. Section 6.1 adds a validation step to the
documented assignment procedure.
5. Various documents and registries previously said to submit
requests via email, but a web form exists for submitting
requests, which caused some confusion around which was to be
used. This is addressed in Section 6.1.
6. Transmission values [transmission-registry] have generally been
allocated as part of ifType allocation, but no guidance existed
as to whether a requester must ask for it or not, and the request
form had no such required field. As a result, IANA has asked the
Designated Expert
designated expert to decide for each allocation, but no relevant
guidance for the Designated Expert designated expert has been documented. This is
remedied in Section 6.2.
4. Interface Sub-Layers Sub-layers and Sub-Types Sub-types
When multiple sub-layers exist below the network layer, each sub-
layer can be represented by its own row in the ifTable with its own
ifType, with the ifStackTable being used to identify the upward and
downward multiplexing relationships between rows. Section 3.1.1 of
[RFC2863] provided provides more discussion, and Section 3.1.2 of that RFC
provided provides guidance for
defining interface sub-layers. More recent experience shows that
those guidelines were phrased in a way that is now too restrictive,
since at the time [RFC2863] was written, MIB modules were the
dominant data model.
This document clarifies that the same guidance also applies to YANG
modules.
Some ifTypes may define sub-types. For example, the tunnel(131)
ifType defines sub-types, sub-types known as "tunnelTypes", where each
tunnelType can have its own MIB and/or YANG module with protocol-specific protocol-
specific information, but there is enough in common that some
information is exposed in a generic IP Tunnel MIB corresponding to
the tunnel(131) ifType.
For requests that involve multiple sub-layers below the network
layer, requests MUST include (or reference) a discussion of the
multiplexing relationships between sub-layers, ideally with a
diagram. Various well-written examples exist of such definitions,
including [RFC3637] section 3.4.1, [RFC4087] section 3.1.1, Section 3.4.1 of [RFC3637], Section 3.1.1 of [RFC4087], and
[RFC5066] section 3.1.1.
Section 3.1.1 of [RFC5066].
Definers of sub-layers and sub-types should consider which model is
more appropriate for their needs. A sub-layer is generally used
whenever either a dynamic relationship exists (i.e., which instances
layer over which other when the set of
instances above or below a given instance can change over time) or a
multiplexing relationship exists with another sub-layer. A sub-type
can be used when neither of these are true, is true but where one interface
type is conceptually a subclass of another interface type, as far as
a management data model is concerned.
In general, the intent of an interface type or sub-type is that its
definition should be sufficient to identify an interoperable
protocol. In some cases, however, a protocol might be defined in a
way that is not sufficient to provide interoperability with other
compliant implementations of that protocol. In such a case, an
ifType definition should discuss whether specific instantiations (or
profiles) of behavior should use a sub-layer model (e.g., each vendor
might layer the protocol over its own sub-layer that provides the
missing details), details) or a sub-type model (i.e., each vendor might
subclass the protocol without any layering relationship). If a sub-
type model is more appropriate, then the data model for the protocol
might include a sub-type identifier so that management software can
discover objects specific to the subtype. sub-type. In either case, such
discussion is important to guide definers of a data model for the
more specific information (i.e., a lower sub-layer or a subtype), sub-type), as
well as the Designated Expert that designated expert, who must review requests for any such
ifTypes or sub-types.
4.1. Alternate Values
Another design decision is whether to reuse an existing ifType or
tunnelType value, possibly using a sub-type or sub-layer model for
refinements, or to use a different value for a new mechanism.
If there is already an entry that could easily satisfy the modeling
and functional requirements for the requested entry, it should be
reused so that applications and tools that use the existing value can
be used without changes. If If, however, the modeling and functional
requirements are significantly different enough such that having
existing applications and tools use the existing value would be seen
as a problem, a new value should be used.
For example, originally different ifType values were used for
different flavors of Ethernet (ethernetCsmacd(6), iso88023Csmacd(7),
fastEther(62), etc.), typically because they were registered by
different vendors. Using different values was, however, seen as
problematic because all were functionally similar, and so [RFC3635] then
deprecated all but ethernetCsmacd(6).
As another example, a udp(8) tunnelType value was defined in
[RFC2667] with the description "The value UDP indicates that the
payload packet is encapsulated within a normal UDP packet (e.g., RFC
1234)." The Teredo tunnel protocol [RFC4380] was later defined and
encapsulates packets over UDP, but the protocol model is quite
different between [RFC1234] and Teredo. For example, [RFC1234]
supports encapsulation of multicast/broadcast traffic traffic, whereas Teredo
does not. As such, it would be more confusing to applications and
tools to represent them using the same tunnel type, and so [RFC4087]
defined a new value for Teredo.
In summary, definers of new interface or tunnel mechanisms should use
a new ifType or tunnelType value rather than reusing reuse an existing value
when key aspects such as the header format or the link model
(point-to-point, (point-
to-point, non-broadcast multi-access, broadcast capable multi-
access, broadcast-capable multi-access,
unidirectional broadcast, etc.) are significantly different from
existing values, but they should reuse the same value when the
differences can be expressed in terms of differing values of existing
objects other than ifType/tunnelType, ifType/tunnelType in the standard YANG or MIB
module.
5. Available Formats
Many registries are available in multiple formats. For example, XML,
HTML, CSV, and plain text are common formats in which many registries
are available. This document clarifies that the [IANAifType-MIB],
[yang-if-type], and [yang-tunnel-type] MIB and YANG modules are
merely additional formats in which the ifType "Interface Types (ifType)" and tunnelType
"Tunnel Types (tunnelType)" registries are available. The MIB and
YANG modules are not separate registries, and the same values are
always present in all formats of the same registry.
The confusion stemmed in part from the fact that the IANA "Protocol
Registries" [protocol-registries] listed the YANG and MIB module
formats separately, as if they were separate registries. However,
the entries for the yang-if-type and iana-tunnel-type YANG modules
said "See ifType definitions registry." registry" and "See tunnelType registry
(mib-2.interface.ifTable.ifEntry.ifType.tunnelType)."
(mib-2.interface.ifTable.ifEntry.ifType.tunnelType)" respectively,
although the entry for the IANAifType-MIB had no such note.
Section 7.1 addresses this.
6. Registration
The IANA policy (using terms defined in [RFC8126]) for registration
is Expert Review, Review for both interface types and tunnel types. The role
of the Designated Expert designated expert in the procedure is to raise possible
concerns about wider implications of proposals for use and deployment
of interface types. While it is recommended that the responsible
Area Director and the IESG take into consideration the Designated
Expert designated
expert opinions, nothing in the procedure empowers the Designated
Expert designated
expert to override properly arrived-at IETF or working group
consensus.
6.1. Procedures
Someone wishing to register a new ifType or tunnelType value MUST:
1. Check the IANA registry to see whether there is already an entry
that could easily satisfy the modeling and functional
requirements for the requested entry. If there is already such
an entry, use it or update the existing specification. Text in
an Internet-Draft, Internet-Draft or part of some other permanently available, stable
specification may be written to clarify the usage of an existing
entry or entries for the desired purpose.
2. Check the IANA registry to see whether there is already some
other entry with the desired name. If there is already an
unrelated entry under the desired name, choose a different name.
3. Prepare a registration request using the template specified in
Section 6.3. The registration request can be contained in an
Internet-Draft, submitted alone, or submitted as part of some other
permanently available, stable specification. The registration
request can also be submitted in some other form (as part of
another document or as a stand-alone document), but the
registration request will be treated as an "IETF Contribution"
under the guidelines of [RFC5378].
4. Submit the registration request (or pointer to a document
containing it) to IANA at iana@iana.org or (if requesting an
ifType) via the web form at <https://www.iana.org/form/iftype>.
Upon receipt of a registration request, the following steps MUST be
followed:
1. IANA checks the submission for completeness; if required
information is missing or any citations are not correct, IANA
will reject the registration request. A registrant can resubmit
a corrected request if desired.
2. IANA requests Expert Review of the registration request against
the corresponding guidelines from this document.
3. The Designated Expert designated expert will evaluate the request against the
criteria.
4. Once the Designated Expert designated expert approves a registration, IANA updates
[ifType-registry], [IANAifType-MIB], and [yang-if-type] to show
the registration for an interface type, or [tunnelType-registry],
[IANAifType-MIB], and [yang-tunnel-type] to show the registration
for a tunnel type. When adding values, IANA should verify that
the updated MIB module and YANG module formats are syntactically
correct before publishing the update. There are various existing
tools or web sites websites that can be used to do this verification.
5. If instead the Designated Expert designated expert does not approve registration
(e.g., for any of the reasons in [RFC8126] section [RFC8126], Section 5), a
registrant can resubmit a corrected request if desired, or the
IESG can override the Designated Expert designated expert and approve it per the
process in Section 3.3 of [RFC8126].
6.2. Media-specific OID-subtree assignments Media-Specific OID-Subtree Assignments
[IANAifType-MIB] notes:
| The relationship between the assignment of ifType values and of
| OIDs to particular media-specific MIBs is solely the purview of
| IANA and is subject to change without notice. Quite often, a
| media-specific MIB's OID-subtree assignment within MIB-II's
| 'transmission' subtree will be the same as its ifType value.
| However, in some circumstances this will not be the case, and
| implementors must not pre-assume any specific relationship between
| ifType values and transmission subtree OIDs.
The advice above remains unchanged, but this document changes the
allocation procedure to streamline the process, so that an ifType
value and a transmission number value with the same value will be
assigned at the same time.
Rationale:
(1) This saves effort in the future since effort if a transmission number is later needed,
deemed necessary, since no IANA request is needed that would
then require another Expert Review.
(2) The transmission numbering space is not scarce, so there seems
to be little need to reserve the number for a different purpose
than what the ifType is for.
(3) The Designated Expert designated expert need not review whether a transmission
number value should be registered when processing each ifType
request, thus reducing the possibility of delaying assignment of
ifType values.
(4) There is no case on record where allocating the same value could
have caused any problem. problems.
6.3. Registration Template
6.3.1. ifType
The following template describes the fields that MUST be supplied in
a registration request suitable for adding to the ifType "Interface Types
(ifType)" registry:
Label for IANA ifType requested: As explained in Section 7.1.1 of
[RFC2578], a label for a named-number enumeration must consist of
one or more letters or digits, up to a maximum of 64 characters,
and the initial character must be a lower-case lowercase letter. (However,
labels longer than 32 characters are not recommended.) Note that
hyphens are not allowed.
Name of IANA ifType requested: A short description (e.g., a protocol
name),
name) suitable to appear in a comment in the registry.
Description of the proposed use of the IANA ifType: Requesters MUST
include answers, either directly or via a link to some a document with
the answers, to the following questions in the explanation of the
proposed use of the IANA IfType:
o
* How would IP run over your ifType?
o
* Would there be another interface sublayer sub-layer between your ifType
and IP?
o
* Would your ifType be vendor-specific or vendor specific / proprietary? (If so,
the label MUST start with a string that shows that. For
example, if your company's name or acronym is xxx, then the
ifType label would be something like xxxSomeIfTypeLabel.)
o
* Would your ifType require or allow vendor-specific extensions?
If so, would the vendor use their own ifType in a sub-layer
below the requested ifType, or a sub-type of the ifType, or some
other mechanism?
Reference, Internet-Draft, or Specification: A link to some a document is
required.
Additional information or comments: Optionally Optional; any additional
comments for IANA or the Designated Expert. designated expert.
6.3.2. tunnelType
Prior to this document, no form existed for tunnelType (and new
tunnelType requests did not need to use the ifType form that did
exist). This document therefore specifies a tunnelType form.
The following template describes the fields that MUST be supplied in
a registration request suitable for adding to the tunnelType "Tunnel Types
(tunnelType)" registry:
Label for IANA tunnelType requested: As explained in Section 7.1.1
of [RFC2578], a label for a named-number enumeration must consist
of one or more letters or digits, up to a maximum of 64
characters, and the initial character must be a lower-case lowercase letter.
(However, labels longer than 32 characters are not recommended.)
Note that hyphens are not allowed.
Name of IANA tunnelType requested: A short description (e.g., a
protocol name), name) suitable to appear in a comment in the registry.
Description of the proposed use of the IANA tunnelType: Requesters
MUST include answers, either directly or via a link to some a document
with the answers, to the following questions in the explanation of
the proposed use of the IANA tunnelType:
o
* How would IP run over your tunnelType?
o
* Would there be another interface sublayer sub-layer between your
tunnelType and IP?
o
* Would your tunnelType be vendor-specific or proprietary? (If
so, the label MUST start with a string that shows that. For
example, if your company's name or acronym is xxx, then the
tunnelType label would be something like
xxxSomeTunnelTypeLabel.)
o
* Would your tunnelType require or allow vendor-specific
extensions? If so, would the vendor use their own tunnelType
in a sub-layer below the requested tunnelType, or some sort of
sub-type of the tunnelType, or some other mechanism?
Reference, Internet-Draft, or Specification: A link to some a document is
required.
Additional information or comments: Optionally any additional
comments for IANA or the Designated Expert. designated expert.
7. IANA Considerations
This entire document is about IANA considerations, but this section
discusses actions taken by and to be taken by IANA. There are three
registries affected:
1. ifType definitions Interface Types (ifType) [ifType-registry]: The registration
process is updated in Section 6.1, and the template is updated in
Section 6.3.1.
2. tunnelType definitions Tunnel Types (tunnelType) [tunnelType-registry]: The registration
process is updated in Section 6.1, and the template is updated in
Section 6.3.2.
3. transmission numbers Transmission Number Values [transmission-registry]: The
assignment process is updated in Section 6.2.
At the time of publication of this document, IANA is unable to
perform some of the actions requested below due to limitations of
their current platform and toolset. In such cases, IANA is requested
to perform these actions as and when the migration to a new platform
that would enable these actions is complete.
7.1. MIB and YANG Modules
The following actions are
IANA is to be taken complete the following to clarify the relationship between
MIB modules, YANG modules, and the relevant registries: registries.
1. Add the The following note has been added to the entry for the IANAifType-MIB at
[protocol-registries]: "This is one of the available formats of
the ifType Interface Types (ifType) and tunnelType Tunnel Types (tunnelType)
registries."
2. Change the The note on the entry for the iana-if-type YANG module at
[protocol-registries] has been updated to read: "This is one of
the available formats of the ifType Interface Types (ifType) registry."
3. Change the The note on the entry for the the iana-tunnel-type YANG module at
[protocol-registries] has been updated to read: "This is one of
the available formats of the tunnelType Tunnel Types (tunnelType)
registry."
4. Create a section for The new "Interface Parameters" category at
[protocol-registries], with [protocol-registries]
includes entries for "Interface Types (ifType)"
[ifType-registry], "Tunnel Types (tunnelType)"
[tunnelType-registry], and "Transmission Number Values"
[transmission-registry].
5. Update the ifType definitions "Interface Types (ifType)" registry [ifType-registry]
to list MIB [IANAifType-MIB] and YANG [yang-if-type] as
Available Formats.
6. Update the tunnelType definitions "Tunnel Types (tunnelType)" registry
[tunnelType-registry] to list MIB [IANAifType-MIB] and YANG
[yang-tunnel-type] as Available Formats, and change the title to "tunnelType
Definitions" for consistency with the [ifType-registry] title. Formats.
7. Replace the [yang-if-type] page with the YANG module content, content
rather than having a page that itself claims to have multiple Available
Formats.
8. Replace the [yang-tunnel-type] page with the YANG module content, content
rather than having a page that itself claims to have multiple Available
Formats.
9. In addition addition, [IANAifType-MIB] is to be updated as follows:
OLD:
| Requests for new values should be made to IANA via email
| (iana@iana.org).
NEW:
| Interface types must not be directly added to the IANAifType-MIB IANAifType-
| MIB MIB module. They must instead be added to the "ifType definitions" "Interface
| Types (ifType)" registry at [ifType-registry].
(Note that [yang-if-type] was previously updated with this
language.)
10. IANA has added this document as a reference in the "Interface
Types (ifType)", "Tunnel Types (tunnelType)", and "Transmission
Number Values" registries, as well as the iana-if-type YANG
Module, iana-tunnel-type YANG Module, and IANAifType-MIB.
7.2. Transmission Number Assignments
Per the discussion in Section 6.2, [ifType-registry] is to be has been updated
as follows:
OLD:
| For every ifType registration, the corresponding transmission
| number value should be registered or marked "Reserved." "Reserved".
NEW:
| For future ifType assignments, an OID-subtree assignment MIB-
II's MIB-II's
| 'transmission' subtree will be made with the same value.
Similarly, the following change is to be has been made to
[transmission-registry]:
OLD:
| For every transmission number registration, the corresponding
| ifType value should be registered or marked "Reserved." "Reserved".
NEW:
| For future transmission number assignments, an 'ifType' will be
| made with the same value.
8. Security Considerations
Since this document does not introduce any technology or protocol,
there are no security issues to be considered for this document
itself.
For security considerations related to MIB and YANG modules that
expose these values, see Section 9 of [RFC2863], Section 6 of
[RFC4087], and Section 3 of [I-D.ietf-softwire-iftunnel]. [RFC8675].
9. References
9.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997, <https://www.rfc-
editor.org/info/rfc2119>.
<https://www.rfc-editor.org/info/rfc2119>.
[RFC2578] McCloghrie, K., Ed., Perkins, D., Ed., and J.
Schoenwaelder, Ed., "Structure of Management Information
Version 2 (SMIv2)", STD 58, RFC 2578,
DOI 10.17487/RFC2578, April 1999, <https://www.rfc-
editor.org/info/rfc2578>.
<https://www.rfc-editor.org/info/rfc2578>.
[RFC2863] McCloghrie, K. and F. Kastenholz, "The Interfaces Group
MIB", RFC 2863, DOI 10.17487/RFC2863, June 2000,
<https://www.rfc-editor.org/info/rfc2863>.
[RFC5378] Bradner, S., Ed. and J. Contreras, Ed., "Rights
Contributors Provide to the IETF Trust", BCP 78, RFC 5378,
DOI 10.17487/RFC5378, November 2008, <https://www.rfc-
editor.org/info/rfc5378>.
<https://www.rfc-editor.org/info/rfc5378>.
[RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for
Writing an IANA Considerations Section in RFCs", BCP 26,
RFC 8126, DOI 10.17487/RFC8126, June 2017,
<https://www.rfc-editor.org/info/rfc8126>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
9.2. Informative References
[I-D.ietf-softwire-iftunnel]
Boucadair, M., Farrer, I., and R. Asati, "Tunnel Interface
Types YANG Module", draft-ietf-softwire-iftunnel-07 (work
in progress), June 2019.
[IANAifType-MIB]
IANA, "IANAifType-MIB", February 2019, "IANAifType-MIB Definitions",
<http://www.iana.org/assignments/ianaiftype-mib>.
[ifType-registry]
IANA, "ifType definitions", June 2019,
<https://www.iana.org/assignments/smi-numbers/smi-
numbers.xhtml#smi-numbers-5>. "Interface Types (ifType)",
<https://www.iana.org/assignments/smi-numbers>.
[protocol-registries]
IANA, "Protocol Registries", June 2019,
<https://www.iana.org/protocols>.
[RFC1234] Provan, D., "Tunneling IPX traffic through IP networks",
RFC 1234, DOI 10.17487/RFC1234, June 1991,
<https://www.rfc-editor.org/info/rfc1234>.
[RFC1573] McCloghrie, K. and F. Kastenholz, "Evolution of the
Interfaces Group of MIB-II", RFC 1573,
DOI 10.17487/RFC1573, January 1994, <https://www.rfc-
editor.org/info/rfc1573>.
<https://www.rfc-editor.org/info/rfc1573>.
[RFC2667] Thaler, D., "IP Tunnel MIB", RFC 2667,
DOI 10.17487/RFC2667, August 1999, <https://www.rfc-
editor.org/info/rfc2667>.
<https://www.rfc-editor.org/info/rfc2667>.
[RFC3635] Flick, J., "Definitions of Managed Objects for the
Ethernet-like Interface Types", RFC 3635,
DOI 10.17487/RFC3635, September 2003, <https://www.rfc-
editor.org/info/rfc3635>.
<https://www.rfc-editor.org/info/rfc3635>.
[RFC3637] Heard, C., C.M., Ed., "Definitions of Managed Objects for the
Ethernet WAN Interface Sublayer", RFC 3637,
DOI 10.17487/RFC3637, September 2003, <https://www.rfc-
editor.org/info/rfc3637>.
<https://www.rfc-editor.org/info/rfc3637>.
[RFC4087] Thaler, D., "IP Tunnel MIB", RFC 4087,
DOI 10.17487/RFC4087, June 2005, <https://www.rfc-
editor.org/info/rfc4087>.
<https://www.rfc-editor.org/info/rfc4087>.
[RFC4380] Huitema, C., "Teredo: Tunneling IPv6 over UDP through
Network Address Translations (NATs)", RFC 4380,
DOI 10.17487/RFC4380, February 2006, <https://www.rfc-
editor.org/info/rfc4380>.
<https://www.rfc-editor.org/info/rfc4380>.
[RFC5066] Beili, E., "Ethernet in the First Mile Copper (EFMCu)
Interfaces MIB", RFC 5066, DOI 10.17487/RFC5066, November
2007, <https://www.rfc-editor.org/info/rfc5066>.
[RFC7224] Bjorklund, M., "IANA Interface Type YANG Module",
RFC 7224, DOI 10.17487/RFC7224, May 2014,
<https://www.rfc-editor.org/info/rfc7224>.
[RFC8675] Boucadair, M., Farrer, I., and R. Asati, "A YANG Data
Model for Tunnel Interface Types", RFC 8675,
DOI 10.17487/RFC8675, November 2019,
<https://www.rfc-editor.org/info/rfc8675>.
[transmission-registry]
IANA, "transmission definitions", June 2019,
<https://www.iana.org/assignments/smi-numbers/smi-
numbers.xhtml#smi-numbers-7>. "Transmission Number Values",
<https://www.iana.org/assignments/smi-numbers>.
[tunnelType-registry]
IANA, "Internet-standard MIB - mib-
2.interface.ifTable.ifEntry.ifType.tunnelType", June 2019,
<https://www.iana.org/assignments/smi-numbers/smi-
numbers.xhtml#smi-numbers-6>. "Tunnel Types (tunnelType)",
<https://www.iana.org/assignments/smi-numbers>.
[yang-if-type]
IANA, "iana-if-type YANG Module", February 2019,
<http://www.iana.org/assignments/iana-if-type>.
[yang-tunnel-type]
IANA, "iana-tunnel-type YANG Module", June 2019,
<https://www.iana.org/assignments/iana-tunnel-type>.
Authors' Addresses
Dave Thaler
Microsoft
EMail:
Email: dthaler@microsoft.com
Dan Romascanu
Independent
EMail:
Email: dromasca@gmail.com