MPLS Working Group                                          L. Andersson
Internet-Draft                                  Bronze Dragon Consulting
Updates: 8029, 8611 (if approved)                                M. Chen
Intended status: Standards Track                      Huawei Techologies
Expires: October February 18, 2020 2021                                  C. Pignataro
                                                           Cisco Systems
                                                                 T. Saad
                                                        Juniper Networks
                                                          April 16,
                                                         August 17, 2020

               Updating the IANA MPLS LSP Ping Parameters
             draft-ietf-mpls-lsp-ping-registries-update-02
             draft-ietf-mpls-lsp-ping-registries-update-03

Abstract

   This document updates RFC 8029 and RFC 8611 that both define IANA
   registries for MPLS LSP Ping.  It also updates the language that is
   used to define description of the
   procedures for the responses are sent when an unkwon unknown or errored erroneous code
   point is found.  The updates are for clarification
   and to clarify and align this name space
   with recent developments.

Status of This Memo

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   provisions of BCP 78 and BCP 79.

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   This Internet-Draft will expire on October February 18, 2020. 2021.

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Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
     1.1.  Requirement Language  . . . . . . . . . . . . . . . . . .   3
   2.  Updating the Message Types, Reply Mode and Return Codes
       Registries  . . . . . . . . . . . . . . . . . . . . . . . . .   3
   3.  Updating the TLV and sub-TLV registries . . . . . . . . . . .   4
     3.1.  General principles the LSP Ping TLV and sub-TLV
           registries  . . . . . . . . . . . . . . . . . . . . . . .   4
       3.1.1.  Unrecognized Experimental and Private Use TLVs and sub-
               TLVs  . . . . . . . . . . . . . . . . . . . . . sub-TLVs . . .   5
     3.2.  Changes to the LSP Ping Registries  . . . . . . . . . . .   5
       3.2.1.  Common Changes to the TLV and sub-TLV Registries  . .   5
   4.  Text Chages/Updates  Updates to Related RFCs . . . . . . . . . . . . . . . . . . .   6
     4.1.  Text Changes  Updates to RFC 8029 . . . . . . . . . . . . . . . . . . .   6
     4.2.  Text Changes  Updates to RFC 8611 . . . . . . . . . . . . . . . . . . .   7
   5.  Security Considerations . . . . . . . . . . . . . . . . . . .   8
   6.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   8
     6.1.  Updates of Message Type, Reply Mode and Return Codes
           Registries  . . . . . . . . . . . . . . . . . . . . . . .   8   9
     6.2.  Common Registration Procedures for TLVs and sub-TLVs  . .   9
     6.3.  IANA Assignments for TLVs and sub-TLVs  . . . . . . . . .   9  10
   7.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  10  11
   8.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  11  12
     8.1.  Normative References  . . . . . . . . . . . . . . . . . .  11  12
     8.2.  Informative References  . . . . . . . . . . . . . . . . .  12  13
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  13  14

1.  Introduction

   When RFC 8029 [RFC8029] was published it contained updates to the
   "Multiprotocol Label Switching (MPLS) Label Switched Paths (LSPs)
   Ping Parameters" IANA name space [IANA-LSP-PING].

   RFC 8611 [RFC8611] updated the LSP Ping IANA registries to match RFC
   8029.  This document further clarifies the entries in those
   registries and makes the definitions more precise.

   This document updates RFC 8029 [[RFC8029] and RFC 8611 [RFC8611] by
   updating two groups of registries as follows:

   First the registries for Message Types [IANA-MT], Reply Modes
   [IANA-RM] and Return Codes [IANA-RC] are updated.  The changes to
   these registries are minor.

   Second, this document updates the TLV and sub-TLV registries.

   o  TLVs [IANA-TLV-reg]

   o  Sub-TLVs for TLVs 1, 16 and 21 [IANA-Sub-1-16-21]

   o  Sub-TLVs for TLV 6 [IANA-Sub-6]

   o  Sub-TLVs for TLV 11 [IANA-Sub-11]

   o  Sub-TLVs for TLV 20 [IANA-Sub-20]

   o  Sub-TLVs for TLV 23 [IANA-Sub-23]

   o  Sub-TLVs for TLV 27 [IANA-Sub-27]

   The registry for sub-TLVs for TLV 9 [IANA-Sub-9] is not updated.

   Third, some code points (TLVs and sub-TLVs) are "mandatory" and or
   "optional".  Contrary to how other RFCs use these words, indicating
   that it is mandatory or optional to include the code points in a
   message, RFC 8029 use the words to indicate that an acction action might or
   might nt not be nesesary.  The necessary.  This document drops the words "mandatory and
   "optional" are
   dropped and the text is changed to focus on what should be doen. done.

1.1.  Requirement Language

   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.

2.  Updating the Message Types, Reply Mode and Return Codes Registries

   The following changes are made to the Message Types, Reply Modes and
   Return Codes [IANA-MT] registries.

   o  In  in the listing of assignments assiged code points the term "Vendor Private
      Use" is changed to "Private Use" Use".

   o  the registration procedure "Specification Required" is changed to
      "RFC Required" and the note "Experimental RFC needed" is removed

   o  a small set of code points (4 code points) for Experimental Use is
      added by reducing the range for "Private Use".

   o  the registration procedure "Specification Required" is changed to "RFC Required" and the note "Experimental RFC needed" is removed range.

   o  the registration procedures "Private Use" and "Experimental Use"
      are added to the table of registration procedures

   o  A note "Not to be assigned" is added for the registration
      procedures "Private Use" and "Experimental Use"

   o  In the list lists that capture the assignment status, the fields that
      are reserved, i.e.  0,  0 (zero), Private Use and Experimental Use are
      clearly marked. marked as such.

      *  In the Return Codes [IANA-RC] [IANA-RC] registry the code point
         "0" has already been assigned.  This assignment is not changed
         and in this registry will not have the code point "0" value "Reserved". continues to be
         assigned as "No Return Code".

   The new Registration Procedures layout Procedures, the registry layouts and the new
   assignments for these registries will be found in Section 6.1.

3.  Updating the TLV and sub-TLV registries

3.1.  General principles the LSP Ping TLV and sub-TLV registries

   The following principles are valid for all the LSP Ping TLV and sub-
   TLV IANA registries

   o  all TLVs and sub-TLVs with a typ type in the the range 0-32767 require a
      response if they are not recognized

   o  all TLVs and sub-TLVs in the range 32768-65535 may be silently
      dropped if the they are not recognized

   The range of each TLV and sub-TLV registry is divided into wto two
   blocks, one with a range from 0 to 32767 for TLVs and sub-TLVs that
   require a response if not recognized.  Another  The other block in the range
   from 32768 to 65535, this block is 65535 for TLVs and sub-TLVs that may be silently dropped
   dropped, possibly stepped over, if not recognized.

   Each of the blocks has code point spaces with the following
   registration procedures:

   o  Standards Action

   o  RFC Required

   o  Experimental Use
   o  Private Use  First come, first served (FCFS)

   The exact defintion defintions of registration these procedures for IANA registries are found in [RFC8126]

3.1.1.  Unrecognized Experimental and Private Use TLVs and sub-TLVs

   Unrecognized TLVs and sub-TLVs for Expereimetal USe in the Experimetal Use, and Privagte Use FCFS
   ranges are handled as any other unrecognised unrecognized TLV or sub-TLV.

   o  If the unrecognized TLV or sub-TLV is from the Experimental Use
      range (37144-37147) (37140-37143) or from the Private Use FCFS range (31748-32767) (31744-32767) a the
      Return Code of 2 ("One or more of the TLVs was not understood")
      will be sent in the echo response.

   o  If the unrecognized TLV or sub-TLV is from the Experimental Use
      range (64512-64515) (64508-64511) or from the Private Use range (64515-65535) (64512-65535)
      the TLVs SHOULD be silently ignored. ignored and possibly be stepped over.

   IETF does not prescribe how recognized or unrecognized Experimental
   Use and Private Use TLVs and sub-TLVs are handled in experimental or
   private networks, that is up to the agency running the experiment or
   the private network.  The statement above relates to describes how standard standards
   compliant implementations will treat the unrecognized TLVs and sub-
   TLVs from these ranges.

3.2.  Changes to the LSP Ping Registries

   This section lists the changes to each MPLS LSP Ping TLV and sub-TLV
   Registry.  Section 6.1, Section 6.2 and Section 6.3 set out outline how the
   new versions of the IANA registries should look, together with the
   registration
   procedures. procedures for each registry.

3.2.1.  Common Changes to the TLV and sub-TLV Registries

   The following changes are made to the TLV and sub-TLV registries.

   o  the registration procedures "Private Use" "First Come Frst Served (FCFS)" and
      "Experimental Use" are added to the table of registration
      procedures

   o  two small sets of code points (2 times 4 (4 code points) points each) for
      experimental use
      Experiemental Use are created.  The first set are for the range
      that requires a response if the TLV or sub-TLV is added, actually they not recognised;
      the sedond set are take from for the range there the TLV or sub-TLV that MAY
      be silently dropped if not recognized.  The code points for "Private Use".
      experimental use are actually taken from the two ranges now called
      "RFC Required".

   o  the registration procedure "Specification Required" is changed to
      "RFC Required" and the note "Experimental RFC needed" is removed

   o  In the listing of assignements assignments the term "Vendor Private Use" is
      changed to "Private Use" "First Come First Served (FCFS)"

   o  In the listing of assignments the range for "Experimental Use" is
      added

   o  A note saying "Not to be assigned" is added for the registration
      procedures "Experimental Use" and "Private Use"

   o  In the list that capture assignment status, the fields that are
      reserved, i.e.  0,  0 (zero) and Experimental Use and Private Use are clearly marked.

   The new Registration Procedures description and the new assignments
   for these registries will be found are shown in Section 6.2 and Section 6.3.

4.  Text Chages/Updates  Updates to Related RFCs

   Some referenced RFCs are using the concept "mandatory TLVs" and
   "mandatory sub-TLVs" to indicate that that, if a TLV or sub-TLV of the
   range 0-16383 or 16384-31743 is present in a message but is not understood, an error
   message need needs to be sent in response.

   The same RFCs use "optional TLVs" and "optional sub-TLVs" to mean
   TLVs or sub-TLVs that can be silently ignored if not recognized.

   Since other RFCs are using use "mandatory TLVs" and "mandatory sub-TLVs" to
   indicate TLVs and sub-TLVs that must be present in a message, we want
   to discontinue the use of "mandatory" to indicate TLVs and sub-
   TLVs sub-TLVs
   that requires an error message in response if not understood.  The
   changes to the RFCs below are intended to align with this practice.

4.1.  Text Changes  Updates to RFC 8029

   Mandatory and optional is used in this way on to indicate whether are response ir
   needed or if at TLV or sub-TLV is not understoond page 14 and 15 in
   Section 3 of RFC 8029.

   The text in those two paragraphs are now changed to: updated to the following:

      TLV and sub-TLV Types less than 32768 (i.e., with the high-order
      bit equal to 0) are TLVs and sub-TLVs that MUST either be
      supported by an implementation or result in the Return Code of 2
      ("One or more of the TLVs was not understood") being sent in the
      echo response.

      An implementation that does not understand or support a received
      TLV or sub-TLV with Type greater than or equal to 32768 (i.e.,
      with the high-order bit equal to 1) SHOULD ignore and step over
      the TLV or sub-TLV, however an implementation MAY send an echo
      response with Return Code 2 ("One or more of the TLVs was not
      understood") as it would have doen done if the high order bit had been
      clear.

   In Section 3.8 of RFC 8029 "mandatory" is used in the same way.  The
   first two paragaraphs paragraphs of this section ar are now changed updated to read: read as
   follows:

      The following TLV is a TLV that MAY be included in an echo reply
      to inform the sender of an echo request icluding that includes TLVs or sub-TLVs sub-
      TLVs Types greater than or equal to 32768 (i.e., with the high-order high-
      order bit equal to 1) are iether nor either not supported by the
      implementation or parsed and found to be in error.

      The Value field contains the TLVs, including sub-TLVs, that were
      not understood, encoded as sub-TLVs.

4.2.  Text Changes  Updates to RFC 8611

   The "Sub-TLVs for TLV Type 6" registry is now updated to align with
   changes defined in this document.

   The registration procedures for the "Sub-TLVs for TLV Type 6"
   registry will now be like this: as follows:

   +-------------+-------------------+---------------------------------+
   | Range       | Registration      | Note                            |
   |             | Procedures        |                                 |
   +-------------+-------------------+---------------------------------+
   | 0-16383     | Standards Action  | This range is for sub-TLVs that |
   |             |                   | require an error message if not |
   |             |                   | recognized.                     |
   | 16384-31743 16384-31739 | RFC Required      | This range is for sub-TLVs that |
   |             |                   | require an error message if not |
   |             |                   | recognized.                     |
   | 31744-32767 31740-31743 | Private Experimental Use  | Not Reserved not to be assigned     |
   | 31744-32767 | FCFS              | This range is for sub-TLVs that |
   |             |                   | require an error message if not |
   |             |                   | recognized.                     |
   | 32768-49161 | Standards Action  | This range is for sub-TLVs that |
   |             |                   | can be silently dropped if not  |
   |             |                   | recognized.                     |
   | 49162-64511 49162-64507 | RFC Required      | This range is for sub-TLVs that |
   |             |                   | can be silently dropped if not  |
   |             |                   | recognized.                     |
   | 64512-65535 64508-64511 | Private Experimental Use  | Not Reserved not to be assigned     |
   | 64512-65535 | FCFS              | This range is for sub-TLVs that |
   |             |                   | can be silently dropped if not  |
   |             |                   | recognized.                     |
   +-------------+-------------------+---------------------------------+

              Sub-TLVs for TLV Type 6 Registration Procedures

5.  Security Considerations

   This document updates IANA registries, some registries.  It also updates terminology
   used to define, and clarifies the terminology related to the code
   points in the registries.  The document does not change how the code-points code-
   points in the registries are used.  This should not create any new
   threats.

   However, the updated terminology and the clarifications improve
   security because it makes it more likely that implementations will be
   consistent and harder to attack.

6.  IANA Considerations

   IANA is requested to update the LSP Ping name space as described in
   this document.

6.1.  Updates of Message Type, Reply Mode and Return Codes Registries

   This section details the updated registration procedures and
   allocations for: for Message Type, Reply Mode and Return Codes registries.

   +---------+--------------------+------------------------------------+
   | Range   | Registration       | Note                               |
   |         | Procedures         |                                    |
   +---------+--------------------+------------------------------------+
   | 0-191   | Standards Action   |                                    |
   | 192-247 | RFC Required       |                                    |
   | 248-251 | Experimental Use   | Not to be assigned                 |
   | 252-255 | Private Use        | Not to be assigned                 |
   +---------+--------------------+------------------------------------+

                    New common registration procedures

   +---------+---------------------------------+-----------------------+
   | Value   | Meaning                         | Reference             |
   +---------+---------------------------------+-----------------------+
   | 0       | Reserved                        | This document         |
   | 1-247   | No changes to the existing      |                       |
   |         | assignments                     |                       |
   | 248-251 | Reserved for Experimental Use   | This document         |
   | 252-255 | Reserved for Private Use        | [RFC8029]             |
   +---------+---------------------------------+-----------------------+

   Common Assignments for the Message Types, Reply Mode and Return Code
                                registries

   Note that for the Return Code registry the an assignment for code point
   zero has been previously assigned, msde, it is not changed but will remain: remains:

   +-------+----------------------------------+------------------------+
   | Value | Meaning                          | Reference              |
   +-------+----------------------------------+------------------------+
   | 0     | No return code                   | [RFC8029]              |
   +-------+----------------------------------+------------------------+

          Assignment for code point 0 in the Return Code registry

6.2.  Common Registration Procedures for TLVs and sub-TLVs

   This section describes the new registration procedures for the TLV
   and sub-TLV registries.  The registry for sub-TLV 9 ([IANA-Sub-9] is
   not changed.

   +-------------+-------------------+---------------------------------+
   | Range       | Registration      | Note                            |
   |             | Procedures        |                                 |
   +-------------+-------------------+---------------------------------+
   | 0-16383     | Standards Action  | This range is for TLVs that anf sub- |
   |             |                   | TLVs that require an error message if not      |
   |             |                   | message if not recognized.      |
   | 16384-31743 16384-31739 | RFC Required      | This range is for TLVs that anf sub- |
   |             |                   | TLVs that require an error message if not      |
   |             |                   | message if not recognized.      |
   | 37144-37147 37140-37144 | Experimental Use  | Not Rserved, not to be assigned     |
   | 31748-32767 | Private Use FCFS              | This range is for TLVs anf sub- | Not to be assigned
   |             |                   | TLVs that require an error      |
   |             |                   | message if not recognized.      |
   | 32768-49161 | Standards Action  | This range is for TLVs that can and sub- |
   |             |                   | TLVs that can be silently dropped if not       |
   |             |                   | dropped if not recognized.      |
   | 49162-64511 49162-64507 | RFC Required      | This range is for TLVs that can and sub- |
   |             |                   | TLVs that can be silently dropped if not       |
   |             |                   | dropped if not recognized.      |
   | 64512-64515 64508-64511 | Experimental Use  | Not Rserved, not to be assigned     |
   | 64515-65535 64512-65535 | Private Use FCFS              | Not to This range is for TLVs and sub- |
   |             |                   | TLVs that can be assigned silently       |
   |             |                   | dropped if not recognized.      |
   +-------------+-------------------+---------------------------------+

                  TLV and sub-TLV Registration Procedures

6.3.  IANA Assignments for TLVs and sub-TLVs

   The two tables in this section describes the updated IANA assignments
   for the TLV and sub-TLV registries.  The registry for sub-TLV 9
   ([IANA-Sub-9] is not changed.

   +-------------+-------------------+------------------+--------------+

   Updated TLV assignments are as follows:

   +--------------+------------------+------------------+--------------+
   | Type         | TLV name         | Reference        | sub-TLV      |
   |              |                  |                  | registry     |
   +-------------+-------------------+------------------+--------------+
   +--------------+------------------+------------------+--------------+
   | 0            | Reserved         | This document    |              |
   | 1-31743 1-31739      | [any]            | No changes to    | [any]        |
   |              |                  | the current      |              |
   |              |                  | registry         |              |
   | 37144-37147 37140-37143  | Reserved for     | This document    | NA           |
   |              | Experimental Use |                  |              |
   | 31748-32767 31744-32767  | Reserved for FCFS             | This document    | NA           |
   |             | Private Use       |                  |              |
   | 32768-64511 32768-64507  | [any]            | No changes to    | [any]        |
   |              |                  | the current      |              |
   |              |                  | registry.        |              |
   | 64512-64515 64508-64511  | Reserved for     | This document    | NA           |
   |              | Experimental Use |                  |              |
   | 64515-65535 645152-65535 | Reserved for FCFS             | This document    | NA           |
   |             | Private Use       |                  |              |
   +-------------+-------------------+------------------+--------------+
   +--------------+------------------+------------------+--------------+

                              TLV Assignments

   Updated Sub-TLV assignments are as follows:

   +-------------+-------------------------------+---------------------+
   | Type        | TLV name                      | Reference           |
   +-------------+-------------------------------+---------------------+
   | 0           | Reserved                      | This document       |
   | 1-31743 1-31739     | [any]                         | No changes to the   |
   |             |                               | current registry    |
   | 37144-37147 37140-37143 | Reserved for Experimental Use | This document       |
   | 31748-32767 31744-32767 | Reserved for Private Use FCFS                          | This document       |
   | 32768-64511 32768-64507 | [any]                         | No changes to the   |
   |             |                               | current registry.   |
   | 64512-64515 64508-64511 | Reserved for Experimental Use | This document       |
   | 64515-65535 64512-65535 | Reserved for Private Use FSFC                          | This document       |
   +-------------+-------------------------------+---------------------+

                            Sub-TLV Assignments

7.  Acknowledgements

   The authors wish to thank Adrian Farrel, who both made very useful
   comments and agreed to serve as the document shepherd.

   The authors also wish to thank Micelle Cotton who very patiently
   worked with us to determine how our registries could and should be
   updated.

   The authors thanks Donald Eatlake for a careful and detailed review.

8.  References

8.1.  Normative References

   [IANA-LSP-PING]
              "Multiprotocol Label Switching (MPLS) Label Switched Paths
              (LSPs) Ping Parameters",
              <https://www.iana.org/assignments/mpls-lsp-ping-
              parameters/mpls-lsp-ping-parameters.xhtml/>.

   [IANA-MT]  "Message Types", <https://www.iana.org/assignments/mpls-
              lsp-ping-parameters/mpls-lsp-ping-
              parameters.xhtml#message-types>.

   [IANA-RC]  "Return Codes", <https://www.iana.org/assignments/mpls-
              lsp-ping-parameters/#return-codes>.

   [IANA-RM]  "Reply Modes", <https://www.iana.org/assignments/mpls-lsp-
              ping-parameters/#reply-modes>.

   [IANA-Sub-1-16-21]
              "Sub-TLVs for TLV Types 1, 16, and 21",
              <https://www.iana.org/assignments/https://www.iana.org/
              assignments/mpls-lsp-ping-parameters/mpls-lsp-ping-
              parameters.xhtml#sub-tlv-1-16-21>.

   [IANA-Sub-11]
              "Sub-TLVs for TLV Type 11",
              <https://www.iana.org/assignments/mpls-lsp-ping-
              parameters/mpls-lsp-ping-parameters/mpls-lsp-ping-
              parameters.xhtml#sub-tlv-11>.

   [IANA-Sub-20]
              "Sub-TLVs for TLV Type 20",
              <https://www.iana.org/assignments/mpls-lsp-ping-
              parameters/mpls-lsp-ping-parameters/mpls-lsp-ping-
              parameters.xhtml#sub-tlv-20>.

   [IANA-Sub-23]
              "Sub-TLVs for TLV Type 23",
              <https://www.iana.org/assignments/mpls-lsp-ping-
              parameters/mpls-lsp-ping-parameters/mpls-lsp-ping-
              parameters.xhtml#sub-tlv-23>.

   [IANA-Sub-27]
              "Sub-TLVs for TLV Type 27",
              <https://www.iana.org/assignments/mpls-lsp-ping-
              parameters/mpls-lsp-ping-parameters/mpls-lsp-ping-
              parameters.xhtml#sub-tlv-27>.

   [IANA-Sub-6]
              "Sub-TLVs for TLV Type 6",
              <https://www.iana.org/assignments/mpls-lsp-ping-
              parameters/mpls-lsp-ping-parameters/mpls-lsp-ping-
              parameters.xhtml#sub-tlv-6>.

   [IANA-TLV-reg]
              "TLVs", <https://www.iana.org/assignments/mpls-lsp-ping-
              parameters/mpls-lsp-ping-parameters.xhtml#tlvs>.

   [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>.

   [RFC8029]  Kompella, K., Swallow, G., Pignataro, C., Ed., Kumar, N.,
              Aldrin, S., and M. Chen, "Detecting Multiprotocol Label
              Switched (MPLS) Data-Plane Failures", RFC 8029,
              DOI 10.17487/RFC8029, March 2017,
              <https://www.rfc-editor.org/info/rfc8029>.

   [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>.

   [RFC8611]  Akiya, N., Swallow, G., Litkowski, S., Decraene, B.,
              Drake, J., and M. Chen, "Label Switched Path (LSP) Ping
              and Traceroute Multipath Support for Link Aggregation
              Group (LAG) Interfaces", RFC 8611, DOI 10.17487/RFC8611,
              June 2019, <https://www.rfc-editor.org/info/rfc8611>.

8.2.  Informative References

   [IANA-Sub-9]
              "Sub-TLVs for TLV Type 9",
              <https://www.iana.org/assignments/mpls-lsp-ping-
              parameters/mpls-lsp-ping-parameters/mpls-lsp-ping-
              parameters.xhtml#sub-tlv-9>.

   [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>.

Authors' Addresses

   Loa Andersson
   Bronze Dragon Consulting

   Email: loa@pi.nu

   Mach Chen
   Huawei Techologies

   Email: mach.chen@huawei.com

   Carlos Pignataro
   Cisco Systems

   Email: cpignata@cisco.com

   Tarek Saad
   Juniper Networks

   Email: tsaad@juniper.net