MPLS Working Group L. Andersson Internet-Draft Bronze Dragon Consulting Updates: 8029, 8611 (if approved) M. Chen Intended status: Standards Track Huawei Techologies Expires: February 18, 2021 C. Pignataro Cisco Systems T. Saad Juniper Networks August 17, 2020 Updating the IANA MPLS LSP Ping Parameters 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 description of the procedures for the responses sent when an unknown or erroneous code point is found. The updates are to clarify and align this name space with recent developments. 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 of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at https://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents 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 February 18, 2021. Copyright Notice Copyright (c) 2020 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents Andersson, et al. Expires February 18, 2021 [Page 1] Internet-Draft LSP Ping Registries August 2020 carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. 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 Use TLVs and 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. Updates to Related RFCs . . . . . . . . . . . . . . . . . . . 6 4.1. Updates to RFC 8029 . . . . . . . . . . . . . . . . . . . 6 4.2. 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 . . . . . . . . . . . . . . . . . . . . . . . 9 6.2. Common Registration Procedures for TLVs and sub-TLVs . . 9 6.3. IANA Assignments for TLVs and sub-TLVs . . . . . . . . . 10 7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 11 8. References . . . . . . . . . . . . . . . . . . . . . . . . . 12 8.1. Normative References . . . . . . . . . . . . . . . . . . 12 8.2. Informative References . . . . . . . . . . . . . . . . . 13 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 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: Andersson, et al. Expires February 18, 2021 [Page 2] Internet-Draft LSP Ping Registries August 2020 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" 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 action might or might not be necessary. This document drops the words "mandatory and "optional" and the text is changed to focus on what should be 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 the listing of assiged code points the term "Vendor Private Use" is changed to "Private Use". o the registration procedure "Specification Required" is changed to "RFC Required" and the note "Experimental RFC needed" is removed Andersson, et al. Expires February 18, 2021 [Page 3] Internet-Draft LSP Ping Registries August 2020 o a small set of code points (4 code points) for Experimental Use is added by reducing the range for "RFC Required" 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 lists that capture the assignment status, the fields that are reserved, i.e. 0 (zero), Private Use and Experimental Use are clearly 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 the code point "0" continues to be assigned as "No Return Code". The new Registration 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 type in 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 they are not recognized The range of each TLV and sub-TLV registry is divided into two blocks, one with a range from 0 to 32767 for TLVs and sub-TLVs that require a response if not recognized. The other block in the range from 32768 to 65535 for TLVs and sub-TLVs that may be silently 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 Andersson, et al. Expires February 18, 2021 [Page 4] Internet-Draft LSP Ping Registries August 2020 o First come, first served (FCFS) The exact defintions of these procedures are found in [RFC8126] 3.1.1. Unrecognized Experimental Use TLVs and sub-TLVs Unrecognized TLVs and sub-TLVs in the Experimetal Use, and FCFS ranges are handled as any other unrecognized TLV or sub-TLV. o If the unrecognized TLV or sub-TLV is from the Experimental Use range (37140-37143) or from the FCFS range (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 (64508-64511) or from the Private Use range (64512-65535) the TLVs SHOULD be silently 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 describes how 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 outline how the new versions of the IANA registries should look, together with the registration 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 "First Come Frst Served (FCFS)" and "Experimental Use" are added to the table of registration procedures o two small sets of code points (4 code points each) for Experiemental Use are created. The first set are for the range that requires a response if the TLV or sub-TLV is not recognised; the sedond set are for the range there the TLV or sub-TLV that MAY be silently dropped if not recognized. The code points for experimental use are actually taken from the two ranges now called "RFC Required". Andersson, et al. Expires February 18, 2021 [Page 5] Internet-Draft LSP Ping Registries August 2020 o the registration procedure "Specification Required" is changed to "RFC Required" and the note "Experimental RFC needed" is removed o In the listing of assignments the term "Vendor Private Use" is changed to "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" o In the list that capture assignment status, the fields that are reserved, i.e. 0 (zero) and Experimental Use are clearly marked. The new Registration Procedures description and the new assignments for these registries are shown in Section 6.2 and Section 6.3. 4. Updates to Related RFCs Some referenced RFCs are using the concept "mandatory TLVs" and "mandatory sub-TLVs" to indicate that, if a TLV or sub-TLV of the range 0-16383 or 16384-31743 in a message is not understood, an error message 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 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 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. Updates to RFC 8029 Mandatory and optional is used 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 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. Andersson, et al. Expires February 18, 2021 [Page 6] Internet-Draft LSP Ping Registries August 2020 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 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 paragraphs of this section are now updated to 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 that includes TLVs or sub- TLVs Types greater than or equal to 32768 (i.e., with the high- order bit equal to 1) are 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. 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 as follows: Andersson, et al. Expires February 18, 2021 [Page 7] Internet-Draft LSP Ping Registries August 2020 +-------------+-------------------+---------------------------------+ | Range | Registration | Note | | | Procedures | | +-------------+-------------------+---------------------------------+ | 0-16383 | Standards Action | This range is for sub-TLVs that | | | | require an error message if not | | | | recognized. | | 16384-31739 | RFC Required | This range is for sub-TLVs that | | | | require an error message if not | | | | recognized. | | 31740-31743 | Experimental Use | 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. | | 49162-64507 | RFC Required | This range is for sub-TLVs that | | | | can be silently dropped if not | | | | recognized. | | 64508-64511 | Experimental Use | 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. 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 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. Andersson, et al. Expires February 18, 2021 [Page 8] Internet-Draft LSP Ping Registries August 2020 6.1. Updates of Message Type, Reply Mode and Return Codes Registries This section details the updated registration procedures and allocations 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 an assignment for code point zero has been previously msde, it is not changed but 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. Andersson, et al. Expires February 18, 2021 [Page 9] Internet-Draft LSP Ping Registries August 2020 +-------------+-------------------+---------------------------------+ | Range | Registration | Note | | | Procedures | | +-------------+-------------------+---------------------------------+ | 0-16383 | Standards Action | This range is for TLVs anf sub- | | | | TLVs that require an error | | | | message if not recognized. | | 16384-31739 | RFC Required | This range is for TLVs anf sub- | | | | TLVs that require an error | | | | message if not recognized. | | 37140-37144 | Experimental Use | Rserved, not to be assigned | | 31748-32767 | FCFS | This range is for TLVs anf sub- | | | | TLVs that require an error | | | | message if not recognized. | | 32768-49161 | Standards Action | This range is for TLVs and sub- | | | | TLVs that can be silently | | | | dropped if not recognized. | | 49162-64507 | RFC Required | This range is for TLVs and sub- | | | | TLVs that can be silently | | | | dropped if not recognized. | | 64508-64511 | Experimental Use | Rserved, not to be assigned | | 64512-65535 | FCFS | This range is for TLVs and sub- | | | | TLVs that can be 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: Andersson, et al. Expires February 18, 2021 [Page 10] Internet-Draft LSP Ping Registries August 2020 +--------------+------------------+------------------+--------------+ | Type | TLV name | Reference | sub-TLV | | | | | registry | +--------------+------------------+------------------+--------------+ | 0 | Reserved | This document | | | 1-31739 | [any] | No changes to | [any] | | | | the current | | | | | registry | | | 37140-37143 | Reserved for | This document | NA | | | Experimental Use | | | | 31744-32767 | FCFS | This document | NA | | 32768-64507 | [any] | No changes to | [any] | | | | the current | | | | | registry. | | | 64508-64511 | Reserved for | This document | NA | | | Experimental Use | | | | 645152-65535 | FCFS | This document | NA | +--------------+------------------+------------------+--------------+ TLV Assignments Updated Sub-TLV assignments are as follows: +-------------+-------------------------------+---------------------+ | Type | TLV name | Reference | +-------------+-------------------------------+---------------------+ | 0 | Reserved | This document | | 1-31739 | [any] | No changes to the | | | | current registry | | 37140-37143 | Reserved for Experimental Use | This document | | 31744-32767 | FCFS | This document | | 32768-64507 | [any] | No changes to the | | | | current registry. | | 64508-64511 | Reserved for Experimental Use | This document | | 64512-65535 | 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. Andersson, et al. Expires February 18, 2021 [Page 11] Internet-Draft LSP Ping Registries August 2020 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", . [IANA-MT] "Message Types", . [IANA-RC] "Return Codes", . [IANA-RM] "Reply Modes", . [IANA-Sub-1-16-21] "Sub-TLVs for TLV Types 1, 16, and 21", . [IANA-Sub-11] "Sub-TLVs for TLV Type 11", . [IANA-Sub-20] "Sub-TLVs for TLV Type 20", . [IANA-Sub-23] "Sub-TLVs for TLV Type 23", . Andersson, et al. Expires February 18, 2021 [Page 12] Internet-Draft LSP Ping Registries August 2020 [IANA-Sub-27] "Sub-TLVs for TLV Type 27", . [IANA-Sub-6] "Sub-TLVs for TLV Type 6", . [IANA-TLV-reg] "TLVs", . [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . [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, . [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017, . [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, . 8.2. Informative References [IANA-Sub-9] "Sub-TLVs for TLV Type 9", . Andersson, et al. Expires February 18, 2021 [Page 13] Internet-Draft LSP Ping Registries August 2020 [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, . 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 Andersson, et al. Expires February 18, 2021 [Page 14]