| Internet Engineering Task Force | M. Veillette, Ed. |
| Internet-Draft | Trilliant Networks Inc. |
| Intended status: Standards Track | A. Pelov, Ed. |
| Expires: August 29, 2020 | I. Petrov, Ed. |
| Acklio | |
| February 26, 2020 |
YANG Schema Item iDentifier (SID)
draft-ietf-core-sid-10
YANG Schema Item iDentifiers (SID) are globally unique 63-bit unsigned integers used to identify YANG items. This document defines the semantics, the registration, and assignment processes of SIDs. To enable the implementation of these processes, this document also defines a file format used to persist and publish assigned SIDs.
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 August 29, 2020.
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 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.
Some of the items defined in YANG [RFC7950] require the use of a unique identifier. In both NETCONF [RFC6241] and RESTCONF [RFC8040], these identifiers are implemented using names. To allow the implementation of data models defined in YANG in constrained devices and constrained networks, a more compact method to identify YANG items is required. This compact identifier, called SID, is encoded using a 63-bit unsigned integer. The limitation to 63-bit unsigned integers allows SIDs to be manipulated more easily on platforms that might otherwise lack native 64-bit unsigned arithmetic. The loss of a single bit of range is not significant given the size of the remaining space.
The following items are identified using SIDs:
It is possible that some protocols use only a subset of the assigned SIDs, for example, for protocols equivalent to NETCONF [RFC6241] like [I-D.ietf-core-comi] the transportation of YANG modules SIDs might be unnecessary. Others protocols might need to be able to transport this information, for example protocols related to discovery such as Constrained YANG Module Library [I-D.ietf-core-yang-library].
SIDs are globally unique integers, a registration system is used in order to guarantee their uniqueness. SIDs are registered in blocks called “SID ranges”.
Assignment of SIDs to YANG items can be automated. For more details how this could be achieved, please consult Appendix B.
SIDs are assigned permanently, items introduced by a new revision of a YANG module are added to the list of SIDs already assigned.
Section 3 provides more details about the registration process of YANG modules and associated SIDs. To enable the implementation of this registry, Section 4 defines a standard file format used to store and publish SIDs.
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.
The following terms are defined in [RFC7950]:
The following term is defined in [RFC8040]:
This specification also makes use of the following terminology:
YANG is a language designed to model data accessed using one of the compatible protocols (e.g. NETCONF [RFC6241], RESCONF [RFC8040] and CoRECONF [I-D.ietf-core-comi]). A YANG module defines hierarchies of data, including configuration, state data, RPCs, actions and notifications.
Many YANG modules are not created in the context of constrained applications. YANG modules can be implemented using NETCONF [RFC6241] or RESTCONF [RFC8040] without the need to assign SIDs.
As needed, authors of YANG modules can assign SIDs to their YANG modules. In order to do that, they should first obtain a SID range from a registry and use that range to assign or generate SIDs to items of their YANG module. The assignments can then be stored in a “.sid” file. For example how this could be achieved, please refer to Appendix C.
Registration of the “.sid” file associated to a YANG module is optional but recommended to promote interoperability between devices and to avoid duplicate allocation of SIDs to a single YANG module. Different registries might have different requirements for the registration and publication of the “.sid” files. For diagram of one of the possibilities, please refer to the activity diagram on Figure 1 in Appendix C.
Each time a YANG module or one of its imported module(s) or included sub-module(s) is updated, a new “.sid” file MAY need to be created. All the SIDs present in the previous version of the “.sid” file MUST be present in the new version as well. The creation of this new version of the “.sid” file SHOULD be performed using an automated tool.
If a new revision requires more SIDs than initially allocated, a new SID range MUST be added to the ‘assignment-ranges’ as defined in Section 4. These extra SIDs are used for subsequent assignments.
For an example of this update process, see activity diagram Figure 2 in Appendix C.
“.sid” files are used to persist and publish SIDs assigned to the different YANG items of a specific YANG module. It has the following structure.
module: ietf-sid-file
+--rw module-name? yang:yang-identifier
+--rw module-revision? revision-identifier
+--rw sid-file-version? sid-file-version-identifier
+--rw dependency-revision* [module-name]
| +--rw module-name yang:yang-identifier
| +--rw module-revision revision-identifier
+--rw assigment-ranges* [entry-point]
| +--rw entry-point sid
| +--rw size uint64
+--rw items* [namespace identifier]
+--rw namespace enumeration
+--rw identifier union
+--rw sid sid
The following YANG module defined the structure of this file, encoding is performed using the rules defined in [RFC7951].
<CODE BEGINS> file "ietf-sid-file@2020-02-05.yang"
module ietf-sid-file {
namespace "urn:ietf:params:xml:ns:yang:ietf-sid-file";
prefix sid;
import ietf-yang-types {
prefix yang;
}
import ietf-restconf {
prefix rc;
}
organization
"IETF Core Working Group";
contact
"Michel Veillette
<mailto:michel.veillette@trilliant.com>
Andy Bierman
<mailto:andy@yumaworks.com>
Alexander Pelov
<mailto:a@ackl.io>";
description
"Copyright (c) 2020 IETF Trust and the persons identified as
authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject to
the license terms contained in, the Simplified BSD License set
forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(https://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX
(https://www.rfc-editor.org/info/rfcXXXX); see the RFC itself
for full legal notices.
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 (RFC 2119) (RFC 8174) when, and only when,
they appear in all capitals, as shown here.
This module defines the structure of the .sid files.
Each .sid file contains the mapping between the different
string identifiers defined by a YANG module and a
corresponding numeric value called SID.";
revision 2020-02-05 {
description
"Initial revision.";
reference
"[I-D.ietf-core-sid] YANG Schema Item iDentifier (SID)";
}
typedef revision-identifier {
type string {
pattern '\d{4}-\d{2}-\d{2}';
}
description
"Represents a date in YYYY-MM-DD format.";
}
typedef sid-file-version-identifier {
type uint64;
description
"Optional attribute that gives information about the .sid file
version.";
}
typedef sid {
type uint64;
description
"YANG Schema Item iDentifier";
reference
"[I-D.ietf-core-sid] YANG Schema Item iDentifier (SID)";
}
typedef schema-node-path {
type string {
pattern
'/[a-zA-Z_][a-zA-Z0-9\-_.]*:[a-zA-Z_][a-zA-Z0-9\-_.]*' +
'(/[a-zA-Z_][a-zA-Z0-9\-_.]*(:[a-zA-Z_][a-zA-Z0-9\-_.]*)?)*';
}
description
"Identifies a schema-node path string for use in the
SID registry. This string format follows the rules
for an instance-identifier, as defined in RFC 7959,
except that no predicates are allowed.
This format is intended to support the YANG 1.1 ABNF
for a schema node identifier, except module names
are used instead of prefixes, as specified in RFC 7951.";
reference
"RFC 7950, The YANG 1.1 Data Modeling Language;
Section 6.5: Schema Node Identifier;
RFC 7951, JSON Encoding of YANG Data;
Section 6.11: The instance-identifier type";
}
rc:yang-data sid-file {
leaf module-name {
type yang:yang-identifier;
description
"Name of the YANG module associated with this .sid file.";
}
leaf module-revision {
type revision-identifier;
description
"Revision of the YANG module associated with this .sid file.
This leaf is not present if no revision statement is
defined in the YANG module.";
}
leaf sid-file-version {
type sid-file-version-identifier;
description
"The version number of the .sid file. .sid files and the version
sequence are specific to a given YANG module revision.
This number starts at zero when there is a YANG module update.
This number can distinguish updates to the SID file which are the result of
new processing, or the result of reported errata.";
}
list dependency-revision {
key "module-name";
description
"Information about the revision of each YANG module that the module in
'module-name' includes used during the .sid file generation.";
leaf module-name {
type yang:yang-identifier;
mandatory true;
description
"Name of the YANG module, dependency of 'module-name', for which
revision information is provided.";
}
leaf module-revision {
type revision-identifier;
mandatory true;
description
"Revision of the YANG module, dependency of 'module-name', for which
revision information is provided.";
}
}
list assigment-ranges {
key "entry-point";
description
"SID range(s) allocated to the YANG module identified by
'module-name' and 'module-revision'.
- The SID range first available value is entry-point and the the last
available value in the range is (entry-point + size - 1).
- The SID ranges specified by all assignment-rages MUST NOT overlap.";
leaf entry-point {
type sid;
mandatory true;
description
"Lowest SID available for assignment.";
}
leaf size {
type uint64;
mandatory true;
description
"Number of SIDs available for assignment.";
}
}
list items {
key "namespace identifier";
description
"Each entry within this list defined the mapping between
a YANG item string identifier and a SID. This list MUST
include a mapping entry for each YANG item defined by
the YANG module identified by 'module-name' and
'module-revision'.";
leaf namespace {
type enumeration {
enum module {
value 0;
description
"All module and submodule names share the same
global module identifier namespace.";
}
enum identity {
value 1;
description
"All identity names defined in a module and its
submodules share the same identity identifier
namespace.";
}
enum feature {
value 2;
description
"All feature names defined in a module and its
submodules share the same feature identifier
namespace.";
}
enum data {
value 3;
description
"The namespace for all data nodes, as defined in YANG.";
}
}
description
"Namespace of the YANG item for this mapping entry.";
}
leaf identifier {
type union {
type yang:yang-identifier;
type schema-node-path;
}
description
"String identifier of the YANG item for this mapping entry.
If the corresponding 'namespace' field is 'module',
'feature', or 'identity', then this field MUST
contain a valid YANG identifier string.
If the corresponding 'namespace' field is 'data',
then this field MUST contain a valid schema node
path.";
}
leaf sid {
type sid;
mandatory true;
description
"SID assigned to the YANG item for this mapping entry.";
}
}
}
}
<CODE ENDS>
This document defines a new type of identifier used to encode data models defined in YANG [RFC7950]. As such, this identifier does not contribute to any new security issues in addition of those identified for the specific protocols or contexts for which it is used.
This document registers one YANG module in the “YANG Module Names” registry [RFC6020]:
The name of this registry is “SID Mega-Range”. This registry is used to record the delegation of the management of a block of SIDs to third parties (such as SDOs or registrars).
Each entry in this registry must include:
The information associated to the Organization name should not be publicly visible in the registry, but should be available. This information includes contact email and phone number and change controller email and phone number.
The IANA policy for future additions to this registry is “Expert Review” [RFC8126].
An organization requesting to manage a SID Range (and thus have an entry in the SID Mega-Range Registry), must ensure the following capacities:
For a first allocation to be provided, the requesting organization must demonstrate a functional registry infrastructure.
On subsequent allocation request(s), the organization must demonstrate the exhaustion of the prior range. These conditions need to be asserted by the assigned expert(s).
If that extra-allocation is done within 3 years from the last allocation, the experts need to discuss this request on the CORE working group mailing list and consensus needs to be obtained before allocating a new Mega-Range.
The initial entry in this registry is allocated to IANA:
| Entry Point | Size | Allocation | Organization name | URL |
|---|---|---|---|---|
| 0 | 1000000 | Public | IANA | iana.org |
Each entry in this registry must include:
The first million SIDs assigned to IANA is sub-divided as follows:
| Entry Point | Size | IANA policy |
|---|---|---|
| 0 | 1,000 | Reserved |
| 1,000 | 59,000 | Expert Review |
| 60,000 | 40,000 | Experimental use |
| 100,000 | 900,000 | Reserved |
Initial entries in this registry are as follows:
| Entry Point | Size | Module name | Document reference |
|---|---|---|---|
| 1000 | 100 | ietf-comi | [I-D.ietf-core-comi] |
| 1100 | 50 | ietf-yang-types | [RFC6991] |
| 1150 | 50 | ietf-inet-types | [RFC6991] |
| 1200 | 50 | iana-crypt-hash | [RFC7317] |
| 1250 | 50 | ietf-netconf-acm | [RFC8341] |
| 1300 | 50 | ietf-sid-file | RFCXXXX |
| 1500 | 100 | ietf-interfaces | [RFC8343] |
| 1600 | 100 | ietf-ip | [RFC8344] |
| 1700 | 100 | ietf-system | [RFC7317] |
| 1800 | 400 | iana-if-type | [RFC7224] |
| 2400 | 50 | ietf-voucher | [RFC8366] |
| 2450 | 50 | ietf-constrained-voucher | [I-D.ietf-anima-constrained-voucher] |
| 2500 | 50 | ietf-constrained-voucher-request | [I-D.ietf-anima-constrained-voucher] |
// RFC Ed.: replace XXXX with RFC number assigned to this draft.
For allocation, RFC publication of the YANG module is required as per [RFC8126]. The YANG module must be registered in the “YANG module Name” registry according to the rules specified in section 14 of [RFC6020].
The name of this registry is “IETF SID Registry”. This registry is used to record the allocation of SIDs for individual YANG module items.
Each entry in this registry must include:
The allocation policy is Expert review. The Expert MUST ensure that the following conditions are met:
Due to the difficulty in changing SID values during IETF document processing, it is expected that most documents will ask for SID allocations using Early Allocations [RFC7120]. The details of the Early Allocation should be included in any Working Group Adoption call. Prior to Working Group Adoption, an internet draft authors can use the experimental SID range (as per Section 6.3.2) for their SIDs allocations or other values that do not create ambiguity with other SID uses (for example they can use a range that comes from a non-IANA managed “SID Mega-Range” registry).
After Working Group Adoption, any modification of a “.sid” file is expected to be discussed on the mailing list of the appropriate Working Groups. Specific attention should be paid to implementers’ opinion after Working Group Last Call if a SID value is to change its meaning. In all cases, a “.sid” file and the SIDs associated with it are subject to change before the publication of an internet draft as an RFC.
During the early use of SIDs, many existing, previously published YANG modules will not have SID allocations. For an allocation to be useful the included YANG modules may also need to have SID allocations made.
The Expert Reviewer who performs the (Early) Allocation analysis will need to go through the list of included YANG modules and perform SID allocations for those modules as well.
At the end of the IETF process all the dependencies of a given module for which SIDs are assigned, should also have SIDs assigned. Those dependencies’ assignments should be permanent (not Early Allocation).
A previously SID-allocated YANG module which changes its references to include a YANG module for which there is no SID allocation needs to repeat the Early Allocation process.
Early Allocations are made with a one-year period, after which they are expired. [RFC7120] indicates that at most one renewal may be made. For the SID allocation a far more lenient stance is desired.
This is driven by the very generous size of the SID space and the often complex and deep dependencies of YANG modules. Often a core module with many dependencies will undergo extensive review, delaying the publication of other documents.
[RFC7120] also says
Note that if a document is submitted for review to the IESG and at the time of submission some early allocations are valid (not expired), these allocations should not be expired while the document is under IESG consideration or waiting in the RFC Editor's queue after approval by the IESG.
None.
The authors would like to thank Andy Bierman, Carsten Bormann, Michael Richardson, Abhinav Somaraju, Peter van der Stok, Laurent Toutain and Randy Turner for their help during the development of this document and their useful comments during the review process.
| [RFC2119] | Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997. |
| [RFC7120] | Cotton, M., "Early IANA Allocation of Standards Track Code Points", BCP 100, RFC 7120, DOI 10.17487/RFC7120, January 2014. |
| [RFC7950] | Bjorklund, M., "The YANG 1.1 Data Modeling Language", RFC 7950, DOI 10.17487/RFC7950, August 2016. |
| [RFC7951] | Lhotka, L., "JSON Encoding of Data Modeled with YANG", RFC 7951, DOI 10.17487/RFC7951, August 2016. |
| [RFC8174] | Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017. |
| [I-D.ietf-anima-constrained-voucher] | Richardson, M., Stok, P. and P. Kampanakis, "Constrained Voucher Artifacts for Bootstrapping Protocols", Internet-Draft draft-ietf-anima-constrained-voucher-07, January 2020. |
| [I-D.ietf-core-comi] | Veillette, M., Stok, P., Pelov, A., Bierman, A. and I. Petrov, "CoAP Management Interface", Internet-Draft draft-ietf-core-comi-08, September 2019. |
| [I-D.ietf-core-yang-library] | Veillette, M. and I. Petrov, "Constrained YANG Module Library", Internet-Draft draft-ietf-core-yang-library-01, January 2020. |
| [RFC6020] | Bjorklund, M., "YANG - A Data Modeling Language for the Network Configuration Protocol (NETCONF)", RFC 6020, DOI 10.17487/RFC6020, October 2010. |
| [RFC6241] | Enns, R., Bjorklund, M., Schoenwaelder, J. and A. Bierman, "Network Configuration Protocol (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011. |
| [RFC6991] | Schoenwaelder, J., "Common YANG Data Types", RFC 6991, DOI 10.17487/RFC6991, July 2013. |
| [RFC7224] | Bjorklund, M., "IANA Interface Type YANG Module", RFC 7224, DOI 10.17487/RFC7224, May 2014. |
| [RFC7317] | Bierman, A. and M. Bjorklund, "A YANG Data Model for System Management", RFC 7317, DOI 10.17487/RFC7317, August 2014. |
| [RFC8040] | Bierman, A., Bjorklund, M. and K. Watsen, "RESTCONF Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017. |
| [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. |
| [RFC8341] | Bierman, A. and M. Bjorklund, "Network Configuration Access Control Model", STD 91, RFC 8341, DOI 10.17487/RFC8341, March 2018. |
| [RFC8343] | Bjorklund, M., "A YANG Data Model for Interface Management", RFC 8343, DOI 10.17487/RFC8343, March 2018. |
| [RFC8344] | Bjorklund, M., "A YANG Data Model for IP Management", RFC 8344, DOI 10.17487/RFC8344, March 2018. |
| [RFC8366] | Watsen, K., Richardson, M., Pritikin, M. and T. Eckert, "A Voucher Artifact for Bootstrapping Protocols", RFC 8366, DOI 10.17487/RFC8366, May 2018. |
The following “.sid” file (ietf-system@2014-08-06.sid) have been generated using the following yang modules:
{
"assignment-ranges": [
{
"entry-point": 1700,
"size": 100
}
],
"module-name": "ietf-system",
"module-revision": "2014-08-06",
"items": [
{
"namespace": "module",
"identifier": "ietf-system",
"sid": 1700
},
{
"namespace": "identity",
"identifier": "authentication-method",
"sid": 1701
},
{
"namespace": "identity",
"identifier": "local-users",
"sid": 1702
},
{
"namespace": "identity",
"identifier": "radius",
"sid": 1703
},
{
"namespace": "identity",
"identifier": "radius-authentication-type",
"sid": 1704
},
{
"namespace": "identity",
"identifier": "radius-chap",
"sid": 1705
},
{
"namespace": "identity",
"identifier": "radius-pap",
"sid": 1706
},
{
"namespace": "feature",
"identifier": "authentication",
"sid": 1707
},
{
"namespace": "feature",
"identifier": "dns-udp-tcp-port",
"sid": 1708
},
{
"namespace": "feature",
"identifier": "local-users",
"sid": 1709
},
{
"namespace": "feature",
"identifier": "ntp",
"sid": 1710
},
{
"namespace": "feature",
"identifier": "ntp-udp-port",
"sid": 1711
},
{
"namespace": "feature",
"identifier": "radius",
"sid": 1712
},
{
"namespace": "feature",
"identifier": "radius-authentication",
"sid": 1713
},
{
"namespace": "feature",
"identifier": "timezone-name",
"sid": 1714
},
{
"namespace": "data",
"identifier": "/ietf-system:set-current-datetime",
"sid": 1715
},
{
"namespace": "data",
"identifier": "/ietf-system:set-current-datetime/
current-datetime",
"sid": 1716
},
{
"namespace": "data",
"identifier": "/ietf-system:system",
"sid": 1717
},
{
"namespace": "data",
"identifier": "/ietf-system:system-restart",
"sid": 1718
},
{
"namespace": "data",
"identifier": "/ietf-system:system-shutdown",
"sid": 1719
},
{
"namespace": "data",
"identifier": "/ietf-system:system-state",
"sid": 1720
},
{
"namespace": "data",
"identifier": "/ietf-system:system-state/clock",
"sid": 1721
},
{
"namespace": "data",
"identifier": "/ietf-system:system-state/clock/boot-datetime",
"sid": 1722
},
{
"namespace": "data",
"identifier": "/ietf-system:system-state/clock/
current-datetime",
"sid": 1723
},
{
"namespace": "data",
"identifier": "/ietf-system:system-state/platform",
"sid": 1724
},
{
"namespace": "data",
"identifier": "/ietf-system:system-state/platform/machine",
"sid": 1725
},
{
"namespace": "data",
"identifier": "/ietf-system:system-state/platform/os-name",
"sid": 1726
},
{
"namespace": "data",
"identifier": "/ietf-system:system-state/platform/os-release",
"sid": 1727
},
{
"namespace": "data",
"identifier": "/ietf-system:system-state/platform/os-version",
"sid": 1728
},
{
"namespace": "data",
"identifier": "/ietf-system:system/authentication",
"sid": 1729
},
{
"namespace": "data",
"identifier": "/ietf-system:system/authentication/user",
"sid": 1730
},
{
"namespace": "data",
"identifier": "/ietf-system:system/authentication/
user-authentication-order",
"sid": 1731
},
{
"namespace": "data",
"identifier": "/ietf-system:system/authentication/user/
authorized-key",
"sid": 1732
},
{
"namespace": "data",
"identifier": "/ietf-system:system/authentication/user/
authorized-key/algorithm",
"sid": 1733
},
{
"namespace": "data",
"identifier": "/ietf-system:system/authentication/user/
authorized-key/key-data",
"sid": 1734
},
{
"namespace": "data",
"identifier": "/ietf-system:system/authentication/user/
authorized-key/name",
"sid": 1735
},
{
"namespace": "data",
"identifier": "/ietf-system:system/authentication/user/
name",
"sid": 1736
},
{
"namespace": "data",
"identifier": "/ietf-system:system/authentication/user/
password",
"sid": 1737
},
{
"namespace": "data",
"identifier": "/ietf-system:system/clock",
"sid": 1738
},
{
"namespace": "data",
"identifier": "/ietf-system:system/clock/timezone-name",
"sid": 1739
},
{
"namespace": "data",
"identifier": "/ietf-system:system/clock/timezone-utc-offset",
"sid": 1740
},
{
"namespace": "data",
"identifier": "/ietf-system:system/contact",
"sid": 1741
},
{
"namespace": "data",
"identifier": "/ietf-system:system/dns-resolver",
"sid": 1742
},
{
"namespace": "data",
"identifier": "/ietf-system:system/dns-resolver/options",
"sid": 1743
},
{
"namespace": "data",
"identifier": "/ietf-system:system/dns-resolver/options/
attempts",
"sid": 1744
},
{
"namespace": "data",
"identifier": "/ietf-system:system/dns-resolver/options/
timeout",
"sid": 1745
},
{
"namespace": "data",
"identifier": "/ietf-system:system/dns-resolver/search",
"sid": 1746
},
{
"namespace": "data",
"identifier": "/ietf-system:system/dns-resolver/server",
"sid": 1747
},
{
"namespace": "data",
"identifier": "/ietf-system:system/dns-resolver/server/name",
"sid": 1748
},
{
"namespace": "data",
"identifier": "/ietf-system:system/dns-resolver/server/
udp-and-tcp",
"sid": 1749
},
{
"namespace": "data",
"identifier": "/ietf-system:system/dns-resolver/server/
udp-and-tcp/address",
"sid": 1750
},
{
"namespace": "data",
"identifier": "/ietf-system:system/dns-resolver/server/
udp-and-tcp/port",
"sid": 1751
},
{
"namespace": "data",
"identifier": "/ietf-system:system/hostname",
"sid": 1752
},
{
"namespace": "data",
"identifier": "/ietf-system:system/location",
"sid": 1753
},
{
"namespace": "data",
"identifier": "/ietf-system:system/ntp",
"sid": 1754
},
{
"namespace": "data",
"identifier": "/ietf-system:system/ntp/enabled",
"sid": 1755
},
{
"namespace": "data",
"identifier": "/ietf-system:system/ntp/server",
"sid": 1756
},
{
"namespace": "data",
"identifier": "/ietf-system:system/ntp/server/
association-type",
"sid": 1757
},
{
"namespace": "data",
"identifier": "/ietf-system:system/ntp/server/iburst",
"sid": 1758
},
{
"namespace": "data",
"identifier": "/ietf-system:system/ntp/server/name",
"sid": 1759
},
{
"namespace": "data",
"identifier": "/ietf-system:system/ntp/server/prefer",
"sid": 1760
},
{
"namespace": "data",
"identifier": "/ietf-system:system/ntp/server/udp",
"sid": 1761
},
{
"namespace": "data",
"identifier": "/ietf-system:system/ntp/server/udp/address",
"sid": 1762
},
{
"namespace": "data",
"identifier": "/ietf-system:system/ntp/server/udp/port",
"sid": 1763
},
{
"namespace": "data",
"identifier": "/ietf-system:system/radius",
"sid": 1764
},
{
"namespace": "data",
"identifier": "/ietf-system:system/radius/options",
"sid": 1765
},
{
"namespace": "data",
"identifier": "/ietf-system:system/radius/options/attempts",
"sid": 1766
},
{
"namespace": "data",
"identifier": "/ietf-system:system/radius/options/timeout",
"sid": 1767
},
{
"namespace": "data",
"identifier": "/ietf-system:system/radius/server",
"sid": 1768
},
{
"namespace": "data",
"identifier": "/ietf-system:system/radius/server/
authentication-type",
"sid": 1769
},
{
"namespace": "data",
"identifier": "/ietf-system:system/radius/server/name",
"sid": 1770
},
{
"namespace": "data",
"identifier": "/ietf-system:system/radius/server/udp",
"sid": 1771
},
{
"namespace": "data",
"identifier": "/ietf-system:system/radius/server/udp/
address",
"sid": 1772
},
{
"namespace": "data",
"identifier": "/ietf-system:system/radius/server/udp/
authentication-port",
"sid": 1773
},
{
"namespace": "data",
"identifier": "/ietf-system:system/radius/server/udp/
shared-secret",
"sid": 1774
}
]
}
Assignment of SIDs to YANG items can be automated, the recommended process to assign SIDs is as follows:
In case of an update to an existing “.sid” file, an additional step is needed that increments the “.sid” file version number. If there was no version number in the previous version of the “.sid” file, 0 is assumed as the version number of the old version of the “.sid” file and the version number is 1 for the new “.sid” file. Apart from that, changes of SID files can also be automated using the same method described above, only unassigned YÀNG items are processed at step #3. Already existing items in the SID file should not be given new SIDs.
Note that “.sid” file versions are specific to a YANG module revision. For each new YANG module or each new revision of an existing YANG module, the version number of the initial “.sid” file should either be 0 or should not be present.
Note also that RPC or action “input” and “output” data nodes MUST always be assigned SID even if they don’t contain data nodes. The reason for this requirement is that other modules can augment the given module and those SIDs might be necessary.
Before assigning SIDs to their YANG modules, YANG module authors must acquire a SID range from a “SID Range Registry”. If the YANG module is part of an IETF draft or RFC, the SID range need to be acquired from the “IETF SID Range Registry” as defined in Section 6.3. For the other YANG modules, the authors can acquire a SID range from any “SID Range Registry” of their choice.
Once the SID range is acquired, the owner can use it to generate “.sid” file/s for his YANG module/s. It is recommended to leave some unallocated SIDs following the allocated range in each “.sid” file in order to allow better evolution of the YANG module in the future. Generation of “.sid” files should be performed using an automated tool. Note that “.sid” files can only be generated for YANG modules and not for submodules.
The following activity diagram summarizes the creation of a YANG module and its associated “.sid” file.
+---------------+
O | Creation of a |
-|- ->| YANG module |
/ \ +---------------+
|
V
/-------------\
/ Standardized \ yes
\ YANG module ? /-------------+
\-------------/ |
| no |
V V
/-------------\ +---------------+
/ Constrained \ yes | SID range |
+-->\ application ? /---->| registration |<----------+
| \-------------/ +---------------+ |
| | no | |
| V V |
| +---------------+ +---------------+ |
+---| YANG module | | SID sub-range | |
| update | | assignment |<----------+
+---------------+ +---------------+ |
| |
V |
+---------------+ +-------------+
| ".sid" file | | Rework YANG |
| generation | | model |
+---------------+ +-------------+
| ^
V |
/----------\ yes |
/ Work in \ -----------+
\ progress /
\----------/
| no
V
/-------------\ /-------------\
/ RFC \ no / Open \ no
\ publication? /---->\ specification?/---+
\-------------/ \-------------/ |
| yes | yes |
| +---------------+ |
V V V
+---------------+ +---------------+
| IANA | | Third party |
| registration | | registration |
+-------+-------+ +-------+-------+
| |
+---------------------------------+
V
[DONE]
Figure 1: SID Lifecycle
The following Activity diagram summarizes the update of a YANG module and its associated “.sid” file.
+---------------+
O | Update of the |
-|- ->| YANG module |
/ \ | or include(s) |
| or import(s) |
+---------------+
|
V
/-------------\
/ New items \ yes
\ created ? /------+
\-------------/ |
| no V
| /-------------\ +----------------+
| / SID range \ yes | Extra sub-range|
| \ exhausted ? /---->| assignment |
| \-------------/ +----------------+
| | no |
| +---------------------+
| |
| V
| +---------------+
| | ".sid" file |
| | update based |
| | on previous |
| | ".sid" file |
| +---------------+
| |
| V
| /-------------\ +---------------+
| / Publicly \ yes | YANG module |
| \ available ? /---->| registration |
| \-------------/ +---------------+
| | no |
+--------------+---------------------+
|
[DONE]
Figure 2: YANG and SID file update