YANG-CBOR: Allocating SID ranges for PEN holders

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 23 May 2022.¶

Copyright Notice

Copyright (c) 2021 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 carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Revised BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Revised BSD License.¶

Table of Contents

1. Introduction

YANG-CBOR, RFC XXXX (draft-ietf-core-yang-cbor) defines YANG Schema Item iDentifiers (YANG SID), globally unique 63-bit unsigned integers used to identify YANG items. RFC YYYY (draft-ietf-core-sid) defines ways to allocate these SIDs on the basis of IANA registries.¶

The present specification uses these SID allocation mechanisms to allocate 100 000 SIDs for each of the first 1 000 000 holders of IANA-registered Private Enterprise Numbers (PENs).¶

We allocate 100 000 mega-ranges, for the SID numbers 300 000 000 000 to 399 999 999 999.¶

The holder of a PEN ppp ppp then can use the SID numbers 3pp ppp p00 000 to 3pp ppp p99 999 for allocation in a scheme defined by the holder.¶

2. Example

The Department for Mathematics and Computer Science of Universität Bremen holds PEN 30810.¶

This confers control over the SID range 303 081 000 000 up to 303 081 099 999 to this PEN holder.¶

3. Discussion

This allocation provides an extremely-low-threshold way for PEN holders to get number space for the YANG SIDs used in their YANG modules. It is, however, not always the approach to recommend to a module author:¶

• The space uses 64-bit numbers. While this is of relatively little consequence due to the delta-encoding used for SIDs in YANG-CBOR, a few further bytes can be saved by allocating the SIDs in one of the mega-ranges that are specifically allocated by an organization (which, for the first 2000 or so, will lead to 32-bit outer deltas).¶
• This space has no infrastructure to discover the YANG module behind a SID. Of course, each PEN holder can provide such infrastructure, but even then the problem remains how to find that infrastructure for a SID. (Search engines may mitigate this somewhat.) On the other hand, relative obscurity may be exactly what a PEN holder wants to achieve by using this mechanism.¶

Relying on the PEN registry might theoretically trigger a land-grab by prospective writers of YANG modules. However, PENs have been around for decades [RFC1065] and such a land-grab hasn't occurred for the other allocations implicitly provided by obtaining a PEN.¶

4. IANA Considerations

This document allocates 100 000 SID mega-ranges as per Section 7.4 of [I-D.ietf-core-sid].¶

The contact for the allocation is: IETF CORE Working Group (core@ietf.org) or IETF Applications and Real-Time Area (art@ietf.org)¶

The allocation policy inside the mega-range is "private". The URL is that of the present specification.¶

The management of the SID blocks of 100 000 SIDs each, 10 such blocks for each mega-range 3nn nnn 000 000, is delegated to the PEN holder for nnn nnx, where x is the sequence number of the SID block in the mega-range (i.e., the PEN holder for nnn nnx controls SID 3nn nnn x00 000 to 3nn nnn x99 999).¶

The technical capacity to ensure the sustained operation of the registry for a period of at least 10 years (as required for registries of class "private") is derived from the capacity of IANA to maintain the PEN number registry.¶

Acknowledgments

This document was inspired by the discussion of the authors of [I-D.ietf-core-yang-cbor] and [I-D.ietf-core-sid] how to handle Rob Wilton's feedback.¶

Author's Address