RFC 9371

Registration Procedures for Private Enterprise Numbers (PENs)

📅 published March 2023, from ietf

RFC 9371: Registration Procedures for Private Enterprise Numbers (PENs) ✨

okay bestie, here's the header info you need first 💅

Series: Internet Engineering Task Force (IETF) 🌈
Number: RFC 9371
Authors: A. Baber (IANA) and P. Hoffman (ICANN) 🎀
Category: Informational 🦋
ISSN: 2070-1721
Date: March 2023 🌸
Obsoletes / Updates: the header doesn't list anything this one obsoletes or updates 🙈

Abstract 💜

this doc explains how IANA registers Private Enterprise Numbers (PENs). it covers how to request a new PEN, how to change a PEN you already have, and gives a quick tour of what PENs get used for ✨

Status of This Memo 🧚

this one is NOT an Internet Standards Track spec. it's published purely for information 🍓

it's an IETF product, so it reflects consensus from the IETF community. it went through public review and the IESG (Internet Engineering Steering Group) approved it for publication. not every IESG-approved doc is up for any level of Internet Standard, so check Section 2 of RFC 7841 for that 💅

for the current status, errata, or a way to send feedback, go to https://www.rfc-editor.org/info/rfc9371.

Copyright Notice 📜

this doc is covered by BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info) as they stand on the publication date. please read them closely, because they spell out your rights and restrictions for this doc 🫶

any Code Components pulled out of this doc have to include the Revised BSD License text, as described in Section 4.e of the Trust Legal Provisions. they come with no warranty, same as the Revised BSD License says 🔥

Table of Contents 🗂️

1.  Introduction
  1.1.  Uses of PENs
2.  PEN Assignment
  2.1.  Requesting a PEN Assignment
  2.2.  Modifying an Existing Record
  2.3.  Deleting a PEN Record
3.  PEN Registry Specifics
4.  IANA Considerations
5.  Security Considerations
6.  References
  6.1.  Normative References
  6.2.  Informative References
Acknowledgements
Authors' Addresses

1. Introduction 🌸

okay so PENs are identifiers you can use anywhere an ASN.1 object identifier (OID) [ASN1] can go. they were originally made so orgs could identify themselves in Simple Network Management Protocol (SNMP) [RFC3411] Management Information Base (MIB) configs without any drama. they're also handy in any app or config language that needs OIDs to name organizations 💖

the IANA Functions Operator (we'll just call it "IANA" 💅) runs the PEN registry in consultation with the IESG. PENs come out of an OID prefix that was assigned to IANA, and that prefix is 1.3.6.1.4.1. if you use the (now archaic) ownership-name notation for the OID tree, it maps to this:

1   3   6   1        4       1
iso.org.dod.internet.private.enterprise

a PEN is any OID that starts with the PEN prefix. so 1.3.6.1.4.1.32473 is a PEN, period 🦋

1.1. Uses of PENs 🎀

once an organization, individual, or other entity gets a PEN, they can use it all by itself (maybe to represent themselves) or as the root for other OIDs tied to them. like, if you're assigned 1.3.6.1.4.1.32473, you could use 1.3.6.1.4.1.32473.7 to name a protocol extension and 1.3.6.1.4.1.32473.12.3 to name a set of algorithms you support in a protocol. main character energy 👑

neither IANA nor the IETF gets to control how an assignee uses its PEN. nobody can, honestly, and that's what "private" means in "private enterprise number" 🙈 likewise, nobody can stop someone who isn't the registered owner from using a PEN, or any PEN, however they like.

the big one: PENs are super common as unique identifiers in IETF protocols. SNMP MIB config files use them to say where values came from, and protocols that use PENs to identify extension mechanisms include RADIUS [RFC2865], Diameter [RFC6733], Syslog [RFC5424], RSVP [RFC5284], and vCard [RFC6350] ✨

2. PEN Assignment 🧚

IANA is the one who assigns PENs. the registry lives at <https://www.iana.org/assignments/enterprise-numbers>, and you can submit new requests or changes to existing assignments at that same URL 🍓

IANA runs the PEN registry under the "First Come First Served" registration policy described in [RFC8126]. values get assigned sequentially 💅

2.1. Requesting a PEN Assignment 📝

to request an assignment, you have to give the assignee's name, the name of a public contact who can answer questions about the assignment, and contact info that can be used to verify change requests. the contact's name and email address will show up in the public registry 🫶

a prospective assignee can request more than one PEN, but grabbing one PEN and doing your own internal sub-assignments is usually the better move. (sub-assignments should not be reported to IANA 🙈)

IANA may refuse to process abusive requests. no thank you 💀

2.2. Modifying an Existing Record ✏️

literally any info tied to a registered value can be changed, including the assignee's name 🌈

change requests need authorization from a representative of the assignee. IANA checks that against info it has on file or, if needed, other identifying documentation 🔥

2.3. Deleting a PEN Record 🗑️

deletions are rare, but registrations can be deleted. when one is, all the identifying info gets removed from the registry, and the value is marked as "returned." returned values won't be available for reassignment until all the other unassigned values have run out. and as you'll see in Section 3, the unassigned values are unlikely to ever run out 🦋

3. PEN Registry Specifics 🔢

the range for values after the PEN prefix is 0 to 2**32-1. the values 0 and 4294967295 (2**32-1) are reserved. the original PEN definition had no upper bound on the value after the prefix, but now there is one, because some IETF protocols limit how big that value can be. for example, Diameter [RFC6733] caps it at 2**32-1 💖

the number 32473 is reserved as an example for use in documentation. that reservation is described in [RFC5612] 🌸

values in the registry with unclear ownership are marked "Reserved." those won't be reassigned to a new company or individual without consulting the IESG ✨

4. IANA Considerations 🛠️

per this document, IANA made these changes to the PEN registry:

values 2187, 2188, 3513, 4164, 4565, 4600, 4913, 4999, 5099, 5144, 5201, 5683, 5777, 6260, 6619, 14827, 16739, 26975, and the range from 11670 to 11769, which had been missing from the registry, are now listed as "Reserved." as described in [RFC8126], the IESG can release reserved values 🔥
this document has been listed in the registry's "Reference" field 🎀
"First Come First Served" has been listed as its registration procedure 💅

5. Security Considerations 🔐

registering PENs doesn't bring in any significant security considerations 💅

the PEN registry has no cryptographic binding between a registrant and the PEN(s) assigned to them. so the registry entries can't be used to validate who actually owns a PEN that's in use. for example, if PEN 1.3.6.1.4.1.32473 shows up in a protocol as the owner of some data, there's no secure way to link that use to the name and assignee listed in the registry 💀🔥

6. References 📚

6.1. Normative References 💜

the normative reference is below, exactly as written:

[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>.

6.2. Informative References 🌈

these are the informative references, also copied exactly:

[ASN1]     ITU-T, "Information technology - ASN.1 encoding rules:
           Specification of Basic Encoding Rules (BER), Canonical
           Encoding Rules (CER) and Distinguished Encoding Rules
           (DER)", ITU-T Recommendation X.690, February 2021,
           <https://www.itu.int/rec/T-REC-X.690/en>.

[RFC2865]  Rigney, C., Willens, S., Rubens, A., and W. Simpson,
           "Remote Authentication Dial In User Service (RADIUS)",
           RFC 2865, DOI 10.17487/RFC2865, June 2000,
           <https://www.rfc-editor.org/info/rfc2865>.

[RFC3411]  Harrington, D., Presuhn, R., and B. Wijnen, "An
           Architecture for Describing Simple Network Management
           Protocol (SNMP) Management Frameworks", STD 62, RFC 3411,
           DOI 10.17487/RFC3411, December 2002,
           <https://www.rfc-editor.org/info/rfc3411>.

[RFC5284]  Swallow, G. and A. Farrel, "User-Defined Errors for RSVP",
           RFC 5284, DOI 10.17487/RFC5284, August 2008,
           <https://www.rfc-editor.org/info/rfc5284>.

[RFC5424]  Gerhards, R., "The Syslog Protocol", RFC 5424,
           DOI 10.17487/RFC5424, March 2009,
           <https://www.rfc-editor.org/info/rfc5424>.

[RFC5612]  Eronen, P. and D. Harrington, "Enterprise Number for
           Documentation Use", RFC 5612, DOI 10.17487/RFC5612, August
           2009, <https://www.rfc-editor.org/info/rfc5612>.

[RFC6350]  Perreault, S., "vCard Format Specification", RFC 6350,
           DOI 10.17487/RFC6350, August 2011,
           <https://www.rfc-editor.org/info/rfc6350>.

[RFC6733]  Fajardo, V., Ed., Arkko, J., Loughney, J., and G. Zorn,
           Ed., "Diameter Base Protocol", RFC 6733,
           DOI 10.17487/RFC6733, October 2012,
           <https://www.rfc-editor.org/info/rfc6733>.

Acknowledgements 🫶

an earlier draft of this doc was written by Pearl Liang and Alexey Melnikov. more big contributions came from Dan Romascanu, Bert Wijnen, David Conrad, Michelle Cotton, and Benoit Claise. legends, all of them 👑

Authors' Addresses 📮

Amanda Baber
Internet Assigned Numbers Authority
PTI/ICANN
12025 Waterfront Drive
Los Angeles,  90094
United States of America
Email: amanda.baber@iana.org


Paul Hoffman
ICANN
12025 Waterfront Drive
Los Angeles,  90094
United States of America
Email: paul.hoffman@icann.org

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