rfc9254.original   rfc9254.txt 
Internet Engineering Task Force M. Veillette, Ed. Internet Engineering Task Force (IETF) M. Veillette, Ed.
Internet-Draft Trilliant Networks Inc. Request for Comments: 9254 Trilliant Networks Inc.
Intended status: Standards Track I. Petrov, Ed. Category: Standards Track I. Petrov, Ed.
Expires: 13 October 2022 Google Switzerland GmbH ISSN: 2070-1721 Google Switzerland GmbH
A. Pelov A. Pelov
Acklio Acklio
C. Bormann C. Bormann
Universität Bremen TZI Universität Bremen TZI
M. Richardson M. Richardson
Sandelman Software Works Sandelman Software Works
11 April 2022 July 2022
CBOR Encoding of Data Modeled with YANG Encoding of Data Modeled with YANG in the Concise Binary Object
draft-ietf-core-yang-cbor-20 Representation (CBOR)
Abstract Abstract
Based on the Concise Binary Object Representation (CBOR, RFC 8949), YANG (RFC 7950) is a data modeling language used to model
this document defines encoding rules for representing configuration configuration data, state data, parameters and results of Remote
data, state data, parameters and results of Remote Procedure Call Procedure Call (RPC) operations or actions, and notifications.
(RPC) operations or actions, and notifications, defined using YANG
(RFC 7950).
Status of This Memo This document defines encoding rules for YANG in the Concise Binary
Object Representation (CBOR) (RFC 8949).
This Internet-Draft is submitted in full conformance with the Status of This Memo
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering This is an Internet Standards Track document.
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 This document is a product of the Internet Engineering Task Force
and may be updated, replaced, or obsoleted by other documents at any (IETF). It represents the consensus of the IETF community. It has
time. It is inappropriate to use Internet-Drafts as reference received public review and has been approved for publication by the
material or to cite them other than as "work in progress." Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of RFC 7841.
This Internet-Draft will expire on 13 October 2022. Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
https://www.rfc-editor.org/info/rfc9254.
Copyright Notice Copyright Notice
Copyright (c) 2022 IETF Trust and the persons identified as the Copyright (c) 2022 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction
2. Terminology and Notation . . . . . . . . . . . . . . . . . . 3 2. Terminology and Notation
3. Properties of the CBOR Encoding . . . . . . . . . . . . . . . 5 3. Properties of the CBOR Encoding
3.1. CBOR diagnostic notation . . . . . . . . . . . . . . . . 6 3.1. CBOR Diagnostic Notation
3.2. YANG Schema Item iDentifier . . . . . . . . . . . . . . . 8 3.2. YANG Schema Item iDentifier
3.3. Name . . . . . . . . . . . . . . . . . . . . . . . . . . 9 3.3. Name
4. Encoding of Representation Nodes . . . . . . . . . . . . . . 11 4. Encoding of Representation Nodes
4.1. The 'leaf' . . . . . . . . . . . . . . . . . . . . . . . 11 4.1. The 'leaf'
4.1.1. Using SIDs in keys . . . . . . . . . . . . . . . . . 11 4.1.1. Using SIDs in Keys
4.1.2. Using names in keys . . . . . . . . . . . . . . . . . 12 4.1.2. Using Names in Keys
4.2. The 'container' and other nodes from the data tree . . . 12 4.2. The 'container' and Other Nodes from the Data Tree
4.2.1. Using SIDs in keys . . . . . . . . . . . . . . . . . 13 4.2.1. Using SIDs in Keys
4.2.2. Using names in keys . . . . . . . . . . . . . . . . . 14 4.2.2. Using Names in Keys
4.3. The 'leaf-list' . . . . . . . . . . . . . . . . . . . . . 15 4.3. The 'leaf-list'
4.3.1. Using SIDs in keys . . . . . . . . . . . . . . . . . 15 4.3.1. Using SIDs in Keys
4.3.2. Using names in keys . . . . . . . . . . . . . . . . . 16 4.3.2. Using Names in Keys
4.4. The 'list' and 'list' entries . . . . . . . . . . . . . . 16 4.4. The 'list' and the 'list' Entries
4.4.1. Using SIDs in keys . . . . . . . . . . . . . . . . . 17 4.4.1. Using SIDs in Keys
4.4.2. Using names in keys . . . . . . . . . . . . . . . . . 19 4.4.2. Using Names in Keys
4.5. The 'anydata' . . . . . . . . . . . . . . . . . . . . . . 21 4.5. The 'anydata'
4.5.1. Using SIDs in keys . . . . . . . . . . . . . . . . . 22 4.5.1. Using SIDs in Keys
4.5.2. Using names in keys . . . . . . . . . . . . . . . . . 23 4.5.2. Using Names in Keys
4.6. The 'anyxml' . . . . . . . . . . . . . . . . . . . . . . 24 4.6. The 'anyxml'
4.6.1. Using SIDs in keys . . . . . . . . . . . . . . . . . 24 4.6.1. Using SIDs in Keys
4.6.2. Using names in keys . . . . . . . . . . . . . . . . . 25 4.6.2. Using Names in Keys
5. Encoding of 'yang-data' extension . . . . . . . . . . . . . . 25 5. Encoding of the 'yang-data' Extension
5.1. Using SIDs in keys . . . . . . . . . . . . . . . . . . . 26 5.1. Using SIDs in Keys
5.2. Using names in keys . . . . . . . . . . . . . . . . . . . 27 5.2. Using Names in Keys
6. Representing YANG Data Types in CBOR . . . . . . . . . . . . 28 6. Representing YANG Data Types in CBOR
6.1. The unsigned integer Types . . . . . . . . . . . . . . . 28 6.1. The Unsigned Integer Types
6.2. The integer Types . . . . . . . . . . . . . . . . . . . . 29 6.2. The Integer Types
6.3. The 'decimal64' Type . . . . . . . . . . . . . . . . . . 29 6.3. The 'decimal64' Type
6.4. The 'string' Type . . . . . . . . . . . . . . . . . . . . 30 6.4. The 'string' Type
6.5. The 'boolean' Type . . . . . . . . . . . . . . . . . . . 30 6.5. The 'boolean' Type
6.6. The 'enumeration' Type . . . . . . . . . . . . . . . . . 31 6.6. The 'enumeration' Type
6.7. The 'bits' Type . . . . . . . . . . . . . . . . . . . . . 32 6.7. The 'bits' Type
6.8. The 'binary' Type . . . . . . . . . . . . . . . . . . . . 34 6.8. The 'binary' Type
6.9. The 'leafref' Type . . . . . . . . . . . . . . . . . . . 35 6.9. The 'leafref' Type
6.10. The 'identityref' Type . . . . . . . . . . . . . . . . . 35 6.10. The 'identityref' Type
6.10.1. SIDs as identityref . . . . . . . . . . . . . . . . 35 6.10.1. SIDs as 'identityref'
6.10.2. Name as identityref . . . . . . . . . . . . . . . . 36 6.10.2. Name as 'identityref'
6.11. The 'empty' Type . . . . . . . . . . . . . . . . . . . . 37 6.11. The 'empty' Type
6.12. The 'union' Type . . . . . . . . . . . . . . . . . . . . 37 6.12. The 'union' Type
6.13. The 'instance-identifier' Type . . . . . . . . . . . . . 38 6.13. The 'instance-identifier' Type
6.13.1. SIDs as instance-identifier . . . . . . . . . . . . 39 6.13.1. SIDs as 'instance-identifier'
6.13.2. Names as instance-identifier . . . . . . . . . . . . 42 6.13.2. Names as 'instance-identifier'
7. Content-Types . . . . . . . . . . . . . . . . . . . . . . . . 43 7. Content-Types
8. Security Considerations . . . . . . . . . . . . . . . . . . . 44 8. Security Considerations
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 45 9. IANA Considerations
9.1. Media-Types Registry . . . . . . . . . . . . . . . . . . 45 9.1. Media Types Registry
9.2. CoAP Content-Formats Registry . . . . . . . . . . . . . . 46 9.2. CoAP Content-Formats Registry
9.3. CBOR Tags Registry . . . . . . . . . . . . . . . . . . . 46 9.3. CBOR Tags Registry
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 47 10. References
10.1. Normative References . . . . . . . . . . . . . . . . . . 47 10.1. Normative References
10.2. Informative References . . . . . . . . . . . . . . . . . 48 10.2. Informative References
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 49 Acknowledgments
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 49 Authors' Addresses
1. Introduction 1. Introduction
The specification of the YANG 1.1 data modeling language [RFC7950] The specification of the YANG 1.1 data modeling language [RFC7950]
defines an XML encoding for data instances, i.e., contents of defines an XML encoding for data instances, i.e., contents of
configuration datastores, state data, RPC inputs and outputs, action configuration datastores, state data, RPC inputs and outputs, action
inputs and outputs, and event notifications. inputs and outputs, and event notifications.
An additional set of encoding rules has been defined in [RFC7951] An additional set of encoding rules has been defined in [RFC7951]
based on the JavaScript Object Notation (JSON) Data Interchange based on "The JavaScript Object Notation (JSON) Data Interchange
Format [RFC8259]. Format" [RFC8259].
The aim of this document is to define a set of encoding rules for the The aim of this document is to define a set of encoding rules for the
Concise Binary Object Representation (CBOR) [RFC8949], collectively Concise Binary Object Representation (CBOR) [RFC8949], collectively
called _YANG-CBOR_. The resulting encoding is more compact compared called "YANG-CBOR". The resulting encoding is more compact compared
to XML and JSON and more suitable for Constrained Nodes and/or to XML and JSON and more suitable for constrained nodes and/or
Constrained Networks as defined by [RFC7228]. constrained networks, as defined by [RFC7228].
2. Terminology and Notation 2. Terminology and Notation
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in "OPTIONAL" in this document are to be interpreted as described in
BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here. capitals, as shown here.
SID values (and the SID deltas computed from them) shown in the
examples are example values; these examples do not allocate the SIDs
shown for specific items in the modules.
The following terms are defined in [RFC7950]: The following terms are defined in [RFC7950]:
* action * action
* anydata * anydata
* anyxml * anyxml
* data node * data node
skipping to change at page 4, line 41 skipping to change at line 182
The following term is defined in [RFC8040]: The following term is defined in [RFC8040]:
* yang-data extension * yang-data extension
The following term is defined in [RFC8791]: The following term is defined in [RFC8791]:
* YANG data structure * YANG data structure
This specification also makes use of the following terminology: This specification also makes use of the following terminology:
* YANG Schema Item iDentifier (YANG SID or simply SID): 63-bit YANG Schema Item iDentifier (or "YANG SID" or simply "SID"):
unsigned integer used to identify different YANG items. 63-bit unsigned integer used to identify different YANG items.
* delta: Difference between the current YANG SID and a reference delta:
YANG SID. A reference YANG SID is defined for each context for Difference between the current YANG SID and a reference YANG SID.
which deltas are used. A reference YANG SID is defined for each context for which deltas
are used.
* absolute SID: YANG SID not encoded as a delta. This is usually absolute SID:
called out explicitly only in positions where normally a delta A YANG SID that is not encoded as a delta. This is usually called
would be found. out explicitly only in positions where normally a delta would be
found.
* representation tree: a YANG data tree, possibly enclosed by a representation tree:
representation of a schema node such as a YANG data structure, a A YANG data tree, possibly enclosed by a representation of a
schema node, such as a YANG data structure, a notification, an
RPC, or an action.
representation node:
A node in a representation tree, i.e., a data tree node, or a
representation of a schema node, such as a YANG data structure, a
notification, an RPC, or an action. notification, an RPC, or an action.
* representation node: a node in a representation tree, i.e., a data item:
tree node, or a representation of a schema node such as a YANG A schema node, an identity, a module, or a feature defined using
data structure, a notification, an RPC, or an action. the YANG modeling language.
* item: A schema node, an identity, a module, or a feature defined list entry:
using the YANG modeling language. The data associated with a single entry of a list (see Section 7.8
of [RFC7950]).
* list entry: the data associated with a single entry of a list (see container-like instance:
Section 7.8 of [RFC7950]). An instance of a container, a YANG data structure, notification
contents, RPC input, RPC output, action input, or action output
(Section 4.2); a list entry in a list (Section 4.4); or an anydata
node (Section 4.5).
* parent (of a representation node): the schema node of the closest parent (of a representation node):
enclosing representation node in which a given representation node The schema node of the closest enclosing representation node in
is defined. which a given representation node is defined.
3. Properties of the CBOR Encoding 3. Properties of the CBOR Encoding
This document defines CBOR encoding rules for YANG data trees and This document defines CBOR encoding rules for YANG data trees and
their subtrees. their subtrees.
A YANG data tree can be enclosed by a representation of a schema node A YANG data tree can be enclosed by a representation of a schema
such as a YANG data structure, a notification, an RPC, or an action; node, such as a YANG data structure, a notification, an RPC, or an
this is called a representation tree. The data tree nodes and the action; this is called a representation tree. The data tree nodes
enclosing schema node representation, if any, are collectively called and the enclosing schema node representation, if any, are
the representation nodes. collectively called the representation nodes.
A representation node such as container, list entry, YANG data A representation node, such as a container, list entry, YANG data
structure, notification, RPC input, RPC output, action input, or structure, notification, RPC input, RPC output, action input, action
action output is serialized using a CBOR map in which each schema output, or anydata node, is serialized using a CBOR map in which each
node defined within is encoded using a key and a value. This schema node defined within is encoded using a key and a value. This
specification supports two types of CBOR keys; YANG Schema Item specification supports two types of CBOR keys: YANG Schema Item
iDentifier (YANG SID) as defined in Section 3.2 and names as defined iDentifier (YANG SID), as defined in Section 3.2, and names, as
in Section 3.3. Each of these key types is encoded using a specific defined in Section 3.3. Each of these key types is encoded using a
CBOR type which allows their interpretation during the specific CBOR type that allows their interpretation during the
deserialization process. Protocols or mechanisms implementing this deserialization process. Protocols or mechanisms implementing this
specification can mandate the use of a specific key type or allow the specification can mandate the use of a specific key type or allow the
generator to choose freely per key. generator to choose freely per key.
In order to minimize the size of the encoded data, the mapping avoids In order to minimize the size of the encoded data, the mapping avoids
any unnecessary meta-information beyond that directly provided by the any unnecessary meta-information beyond that directly provided by the
CBOR basic generic data model (Section 2 of [RFC8949]). For CBOR basic generic data model (Section 2 of [RFC8949]). For
instance, CBOR tags are used solely in the case of an absolute SID, instance, CBOR tags are used solely in the case of an absolute SID,
anyxml data nodes, or the union datatype, to distinguish explicitly anyxml data nodes, or the union datatype to explicitly distinguish
the use of different YANG datatypes encoded using the same CBOR major the use of different YANG datatypes encoded using the same CBOR major
type. type.
Unless specified otherwise by the protocol or mechanism implementing Unless specified otherwise by the protocol or mechanism implementing
this specification, the indefinite length encoding as defined in this specification, the indefinite length encoding, as defined in
Section 3.2 of [RFC8949] SHALL be supported by the CBOR decoders Section 3.2 of [RFC8949], SHALL be supported by the CBOR decoders
employed with YANG-CBOR. (This enables an implementation to begin employed with YANG-CBOR. (This enables an implementation to begin
emitting an array or map before the number of entries in that emitting an array or map before the number of entries in that
structure is known, possibly also avoiding excessive locking or race structure is known, possibly also avoiding excessive locking or race
conditions. On the other hand, it deprives the receiver of the conditions. On the other hand, it deprives the receiver of the
encoded data from advance announcement about some size information, encoded data from advance announcement about some size information,
so a generator should choose indefinite length encoding only when so a generator should choose indefinite length encoding only when
these benefits do accrue.) these benefits do accrue.)
Data nodes implemented using a CBOR array, map, byte string, or text Data nodes implemented using a CBOR array, map, byte string, or text
string can be instantiated but empty. In this case, they are encoded string can be instantiated but empty. In this case, they are encoded
with a length of zero. with a length of zero.
When representation nodes are serialized using the rules defined by When representation nodes are serialized using the rules defined by
this specification as part of an application payload, the payload this specification as part of an application payload, the payload
SHOULD include information that would allow a stateless way to SHOULD include information that would allow each node to be
identify each node, such as the SID number associated with the node, identified in a stateless way, for instance, the SID number
SID delta from another SID in the application payload, the namespace associated with the node, the SID delta from another SID in the
qualified name, or the instance-identifier. application payload, the namespace-qualified name, or the instance-
identifier.
Examples in Section 4 include a root CBOR map with a single entry Examples in Section 4 include a root CBOR map with a single entry
having a key set to either a namespace qualified name or a SID. This having a key set to either a namespace-qualified name or a SID. This
root CBOR map is provided only as a typical usage example and is not root CBOR map is provided only as a typical usage example and is not
part of the present encoding rules. Only the value within this CBOR part of the present encoding rules. Only the value within this CBOR
map is compulsory. map is compulsory.
3.1. CBOR diagnostic notation 3.1. CBOR Diagnostic Notation
Within this document, CBOR binary contents are represented using an Within this document, CBOR binary contents are represented using an
equivalent textual form called CBOR diagnostic notation as defined in equivalent textual form called CBOR diagnostic notation, as defined
Section 8 of [RFC8949]. This notation is used strictly for in Section 8 of [RFC8949]. This notation is used strictly for
documentation purposes and is never used in the data serialization. documentation purposes and is never used in the data serialization.
Table 1 below provides a summary of this notation. Table 1 below provides a summary of this notation.
+==========+======+====================+===========+==========+ +==========+======+====================+===========+==========+
| CBOR | CBOR | Diagnostic | Example | CBOR | | CBOR | CBOR | Diagnostic | Example | CBOR |
| content | type | notation | | encoding | | Content | Type | Notation | | Encoding |
+==========+======+====================+===========+==========+ +==========+======+====================+===========+==========+
| Unsigned | 0 | Decimal digits | 123 | 18 7B | | Unsigned | 0 | Decimal digits | 123 | 18 7B |
| integer | | | | | | integer | | | | |
+----------+------+--------------------+-----------+----------+ +----------+------+--------------------+-----------+----------+
| Negative | 1 | Decimal digits | -123 | 38 7A | | Negative | 1 | Decimal digits | -123 | 38 7A |
| integer | | prefixed by a | | | | integer | | prefixed by a | | |
| | | minus sign | | | | | | minus sign | | |
+----------+------+--------------------+-----------+----------+ +----------+------+--------------------+-----------+----------+
| Byte | 2 | Hexadecimal value | h'F15C' | 42 F15C | | Byte | 2 | Hexadecimal value | h'F15C' | 42 F15C |
| string | | enclosed between | | | | string | | enclosed between | | |
skipping to change at page 7, line 46 skipping to change at line 332
| Boolean | 7/20 | false | false | F4 | | Boolean | 7/20 | false | false | F4 |
+----------+------+--------------------+-----------+----------+ +----------+------+--------------------+-----------+----------+
| | 7/21 | true | true | F5 | | | 7/21 | true | true | F5 |
+----------+------+--------------------+-----------+----------+ +----------+------+--------------------+-----------+----------+
| Null | 7/22 | null | null | F6 | | Null | 7/22 | null | null | F6 |
+----------+------+--------------------+-----------+----------+ +----------+------+--------------------+-----------+----------+
| Not | 7/23 | undefined | undefined | F7 | | Not | 7/23 | undefined | undefined | F7 |
| assigned | | | | | | assigned | | | | |
+----------+------+--------------------+-----------+----------+ +----------+------+--------------------+-----------+----------+
Table 1: CBOR diagnostic notation summary Table 1: CBOR Diagnostic Notation Summary
Note: CBOR binary contents shown in this specification are annotated Note: CBOR binary contents shown in this specification are annotated
with comments. These comments are delimited by slashes ("/") as with comments. These comments are delimited by slashes ("/"), as
defined in [RFC8610] Appendix G.6. defined in Appendix G.6 of [RFC8610].
3.2. YANG Schema Item iDentifier 3.2. YANG Schema Item iDentifier
Some of the items defined in YANG [RFC7950] require the use of a Some of the items defined in YANG [RFC7950] require the use of a
unique identifier. In both Network Configuration Protocol (NETCONF) unique identifier. In both the Network Configuration Protocol
[RFC6241] and RESTCONF [RFC8040], these identifiers are implemented (NETCONF) [RFC6241] and RESTCONF [RFC8040], these identifiers are
using text strings. To allow the implementation of data models implemented using text strings. To allow the implementation of data
defined in YANG in constrained devices and constrained networks, a models defined in YANG in constrained devices and constrained
more compact method to identify YANG items is required. This compact networks, a more compact method to identify YANG items is required.
identifier, called YANG Schema Item iDentifier, is an unsigned This compact identifier, called "YANG Schema Item iDentifier", is an
integer limited to 63 bits of range (i.e., 0..9223372036854775807 or unsigned integer limited to 63 bits of range (i.e.,
0..0x7fffffffffffffff). The following items are identified using 0..9223372036854775807 or 0..0x7fffffffffffffff). The following
YANG SIDs (often shortened to SIDs): items are identified using YANG SIDs (often shortened to SIDs):
* identities * identities
* data nodes * data nodes
* RPCs and associated input(s) and output(s) * RPCs and associated input(s) and output(s)
* actions and associated input(s) and output(s) * actions and associated input(s) and output(s)
* YANG data structures * YANG data structures
* notifications and associated information * notifications and associated information
* YANG modules and features * YANG modules and features
Note that any structuring of modules into submodules is transparent | Note that any structuring of modules into submodules is
to YANG-CBOR: SIDs are not allocated for the names of submodules, and | transparent to YANG-CBOR: SIDs are not allocated for the names
any items within a submodule are effectively allocated SIDs as part | of submodules, and any items within a submodule are effectively
of processing the module that includes them. | allocated SIDs as part of processing the module that includes
| them.
To minimize their size, SIDs used as keys in CBOR maps are encoded To minimize their size, SIDs used as keys in CBOR maps are encoded
using deltas, i.e., signed (negative or unsigned) integers that are using deltas, i.e., signed (negative or unsigned) integers that are
added to the reference SID applying to the map. The reference SID of added to the reference SID applying to the map. The reference SID of
an outermost map is zero, unless a different reference SID is an outermost map is zero, unless a different reference SID is
unambiguously conferred from the environment in which the outermost unambiguously conferred from the environment in which the outermost
map is used. The reference SID of a map that is most directly map is used. The reference SID of a map that is most directly
embedded in a map entry with a name-based key is zero. For all other embedded in a map entry with a name-based key is zero. For all other
maps, the reference SID is the SID computed for the map entry it is maps, the reference SID is the SID computed for the map entry it is
most directly embedded in. (The embedding may be indirect if an most directly embedded in. (The embedding may be indirect if an
skipping to change at page 9, line 14 skipping to change at line 394
Thus, conversion from SIDs to deltas and back to SIDs is a stateless Thus, conversion from SIDs to deltas and back to SIDs is a stateless
process solely based on the data serialized or deserialized combined process solely based on the data serialized or deserialized combined
with, potentially, an outermost reference SID unambiguously conferred with, potentially, an outermost reference SID unambiguously conferred
by the environment. by the environment.
Mechanisms and processes used to assign SIDs to YANG items and to Mechanisms and processes used to assign SIDs to YANG items and to
guarantee their uniqueness are outside the scope of the present guarantee their uniqueness are outside the scope of the present
specification. If SIDs are to be used, the present specification is specification. If SIDs are to be used, the present specification is
used in conjunction with a specification defining this management. A used in conjunction with a specification defining this management. A
related document, [I-D.ietf-core-sid], is intended to serve as the related document, i.e., [CORE-SID], is intended to serve as the
definitive way to assign SID values for YANG modules managed by the definitive way to assign SID values for YANG modules managed by the
IETF, and recommends itself for YANG modules managed by non-IETF IETF and recommends itself for YANG modules managed by non-IETF
entities, as well. The present specification has been designed to entities, as well. The present specification has been designed to
allow different methods of assignment to be used within separate allow different methods of assignment to be used within separate
domains. domains.
To provide implementations with a way to internally indicate the To provide implementations with a way to internally indicate the
absence of a SID, the SID value 0 is reserved and will not be absence of a SID, the SID value 0 is reserved and will not be
allocated; it is not used in interchange. allocated; it is not used in interchange.
3.3. Name 3.3. Name
This specification also supports the encoding of YANG item This specification also supports the encoding of YANG item
identifiers as text strings, similar to those used by the JSON identifiers as text strings, similar to those used by the JSON
Encoding of Data Modeled with YANG [RFC7951]. This approach can be encoding of data modeled with YANG [RFC7951]. This approach can be
used to avoid the management overhead associated with SID allocation. used to avoid the management overhead associated with SID allocation.
The main drawback is the significant increase in size of the encoded The main drawback is the significant increase in size of the encoded
data. data.
YANG item identifiers implemented using names MUST be in one of the YANG item identifiers implemented using names MUST be in one of the
following forms: following forms:
* simple -- the identifier of the YANG item (i.e., schema node or * simple -- the identifier of the YANG item (i.e., schema node or
identity). identity).
* namespace qualified -- the identifier of the YANG item is prefixed * namespace-qualified -- the identifier of the YANG item is prefixed
with the name of the module in which this item is defined, with the name of the module in which this item is defined,
separated by the colon character (":"). separated by the colon character (":").
The name of a module determines the namespace of all YANG items The name of a module determines the namespace of all YANG items
defined in that module. If an item is defined in a submodule, then defined in that module. If an item is defined in a submodule, then
the namespace qualified name uses the name of the main module to the namespace-qualified name uses the name of the main module to
which the submodule belongs. which the submodule belongs.
ABNF syntax [RFC5234] of a name is shown in Figure 1, where the ABNF syntax [RFC5234] of a name is shown in Figure 1, where the
production for "identifier" is defined in Section 14 of [RFC7950]. production for "identifier" is defined in Section 14 of [RFC7950].
name = [identifier ":"] identifier name = [identifier ":"] identifier
Figure 1: ABNF Production for a simple or namespace qualified name Figure 1: ABNF Production for a Simple or Namespace-Qualified Name
A namespace qualified name MUST be used for all members of a top- A namespace-qualified name MUST be used for all members of a top-
level CBOR map and then also whenever the namespaces of the level CBOR map and then also whenever the namespaces of the
representation node and its parent node are different. In all other representation node and its parent node are different. In all other
cases, the simple form of the name MUST be used. cases, the simple form of the name MUST be used.
Definition example: Definition example:
module example-foomod { module example-foomod {
container top { container top {
leaf foo { leaf foo {
type uint8; type uint8;
skipping to change at page 10, line 45 skipping to change at line 474
CBOR diagnostic notation: CBOR diagnostic notation:
{ {
"example-foomod:top": { "example-foomod:top": {
"foo": 54, "foo": 54,
"example-barmod:bar": true "example-barmod:bar": true
} }
} }
Both the 'top' container and the 'bar' leaf defined in a different Both the 'top' container and the 'bar' leaf defined in a different
YANG module as its parent container are encoded as namespace YANG module as its parent container are encoded as namespace-
qualified names. The 'foo' leaf defined in the same YANG module as qualified names. The 'foo' leaf defined in the same YANG module as
its parent container is encoded as simple name. its parent container is encoded as a simple name.
4. Encoding of Representation Nodes 4. Encoding of Representation Nodes
Representation nodes defined using the YANG modeling language are Representation nodes defined using the YANG modeling language are
encoded using CBOR [RFC8949] based on the rules defined in this encoded using CBOR [RFC8949], based on the rules defined in this
section. We assume that the reader is already familiar with both section. We assume that the reader is already familiar with both
YANG [RFC7950] and CBOR [RFC8949]. YANG [RFC7950] and CBOR [RFC8949].
4.1. The 'leaf' 4.1. The 'leaf'
A 'leaf' MUST be encoded accordingly to its datatype using one of the A 'leaf' MUST be encoded accordingly to its datatype using one of the
encoding rules specified in Section 6. encoding rules specified in Section 6.
The following examples show the encoding of a 'hostname' leaf using a The following examples show the encoding of a 'hostname' leaf using a
SID or a name. SID or a name.
skipping to change at page 11, line 36 skipping to change at line 509
+ '([a-zA-Z0-9_]([a-zA-Z0-9\-_]){0,61})?[a-zA-Z0-9]\.?)' + '([a-zA-Z0-9_]([a-zA-Z0-9\-_]){0,61})?[a-zA-Z0-9]\.?)'
+ '|\.'; + '|\.';
length "1..253"; length "1..253";
} }
} }
leaf hostname { leaf hostname {
type inet:domain-name; type inet:domain-name;
} }
4.1.1. Using SIDs in keys 4.1.1. Using SIDs in Keys
As with all examples below, the delta in the outermost map assumes a As with all examples below, the delta in the outermost map assumes a
reference YANG SID (current schema node) of 0. reference YANG SID (current schema node) of 0.
CBOR diagnostic notation: CBOR diagnostic notation:
{ {
1752 : "myhost.example.com" / hostname (SID 1752) / 1752 : "myhost.example.com" / hostname (SID 1752) /
} }
CBOR encoding: CBOR encoding:
A1 # map(1) A1 # map(1)
19 06D8 # unsigned(1752) 19 06D8 # unsigned(1752)
72 # text(18) 72 # text(18)
6D79686F73742E6578616D706C652E636F6D # "myhost.example.com" 6D79686F73742E6578616D706C652E636F6D # "myhost.example.com"
4.1.2. Using names in keys 4.1.2. Using Names in Keys
CBOR diagnostic notation: CBOR diagnostic notation:
{ {
"ietf-system:hostname" : "myhost.example.com" "ietf-system:hostname" : "myhost.example.com"
} }
CBOR encoding: CBOR encoding:
A1 # map(1) A1 # map(1)
74 # text(20) 74 # text(20)
696574662D73797374656D3A686F73746E616D65 696574662D73797374656D3A686F73746E616D65
72 # text(18) 72 # text(18)
6D79686F73742E6578616D706C652E636F6D 6D79686F73742E6578616D706C652E636F6D
4.2. The 'container' and other nodes from the data tree 4.2. The 'container' and Other Nodes from the Data Tree
Instances of containers, YANG data structures, notification contents, Instances of containers, YANG data structures, notification contents,
RPC inputs, RPC outputs, action inputs, and action outputs MUST be RPC inputs, RPC outputs, action inputs, and action outputs MUST be
encoded using a CBOR map data item (major type 5). The same encoding encoded using a CBOR map data item (major type 5). The same encoding
is also used for the list entries in a list (Section 4.4). A map is also used for the list entries in a list (Section 4.4) and for
consists of pairs of data items, with each pair consisting of a key anydata nodes (Section 4.5). Collectively, we speak of these
and a value. Each key within the CBOR map is set to a schema node instances as "container-like instances".
identifier, each value is set to the value of this representation
node according to the instance datatype.
This specification supports two types of CBOR map keys; SID as A map consists of pairs of data items, with each pair consisting of a
defined in Section 3.2 and names as defined in Section 3.3. key and a value. Each key within the CBOR map is set to a schema
node identifier, and each value is set to the value of this
representation node according to the instance datatype.
This specification supports two types of CBOR map keys: SID, as
defined in Section 3.2, and names, as defined in Section 3.3.
The following examples show the encoding of a 'system-state' The following examples show the encoding of a 'system-state'
container representation instance using SIDs or names. container representation instance using SIDs or names.
Definition example adapted from [RFC6991] and [RFC7317]: Definition example adapted from [RFC6991] and [RFC7317]:
typedef date-and-time { typedef date-and-time {
type string { type string {
pattern '\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}(\.\d+)?' pattern '\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}(\.\d+)?'
+ '(Z|[\+\-]\d{2}:\d{2})'; + '(Z|[\+\-]\d{2}:\d{2})';
skipping to change at page 13, line 25 skipping to change at line 585
leaf current-datetime { leaf current-datetime {
type date-and-time; type date-and-time;
} }
leaf boot-datetime { leaf boot-datetime {
type date-and-time; type date-and-time;
} }
} }
} }
4.2.1. Using SIDs in keys 4.2.1. Using SIDs in Keys
In the context of containers and other nodes from the data tree, CBOR In the context of containers and other nodes from the data tree, CBOR
map keys within inner CBOR maps can be encoded using deltas (bare map keys within inner CBOR maps can be encoded using deltas (bare
integers) or absolute SIDs (tagged with tag number 47). integers) or absolute SIDs (tagged with tag number 47).
Delta values are computed as follows: Delta values are computed as follows:
* In the case of a 'container', deltas are equal to the SID of the * In the case of a 'container', deltas are equal to the SID of the
current representation node minus the SID of the parent current representation node minus the SID of the parent
'container'. 'container'.
skipping to change at page 14, line 28 skipping to change at line 637
A1 # map(1) A1 # map(1)
01 # unsigned(1) 01 # unsigned(1)
A2 # map(2) A2 # map(2)
02 # unsigned(2) 02 # unsigned(2)
78 1A # text(26) 78 1A # text(26)
323031352D31302D30325431343A34373A32345A2D30353A3030 323031352D31302D30325431343A34373A32345A2D30353A3030
01 # unsigned(1) 01 # unsigned(1)
78 1A # text(26) 78 1A # text(26)
323031352D30392D31355430393A31323A35385A2D30353A3030 323031352D30392D31355430393A31323A35385A2D30353A3030
Figure 2: System state clock encoding Figure 2: System State Clock Encoding
4.2.2. Using names in keys 4.2.2. Using Names in Keys
CBOR map keys implemented using names MUST be encoded using a CBOR CBOR map keys implemented using names MUST be encoded using a CBOR
text string data item (major type 3). A namespace-qualified name text string data item (major type 3). A namespace-qualified name
MUST be used each time the namespace of a representation node and its MUST be used each time the namespace of a representation node and its
parent differ. In all other cases, the simple form of the name MUST parent differ. In all other cases, the simple form of the name MUST
be used. Names and namespaces are defined in Section 4 of [RFC7951]. be used. Names and namespaces are defined in Section 4 of [RFC7951].
The following example shows the encoding of a 'system' container The following example shows the encoding of a 'system' container
representation node instance using names. representation node instance using names.
skipping to change at page 15, line 28 skipping to change at line 686
78 1A # text(26) 78 1A # text(26)
323031352D30392D31355430393A31323A35385A2D30353A3030 323031352D30392D31355430393A31323A35385A2D30353A3030
4.3. The 'leaf-list' 4.3. The 'leaf-list'
A leaf-list MUST be encoded using a CBOR array data item (major type A leaf-list MUST be encoded using a CBOR array data item (major type
4). Each entry of this array MUST be encoded accordingly to its 4). Each entry of this array MUST be encoded accordingly to its
datatype using one of the encoding rules specified in Section 6. datatype using one of the encoding rules specified in Section 6.
The following example shows the encoding of the 'search' leaf-list The following example shows the encoding of the 'search' leaf-list
representation node instance containing two entries, "ietf.org" and representation node instance containing two entries: "ietf.org" and
"ieee.org". "ieee.org".
Definition example adapted from [RFC6991] and [RFC7317]: Definition example adapted from [RFC6991] and [RFC7317]:
typedef domain-name { typedef domain-name {
type string { type string {
pattern pattern
'((([a-zA-Z0-9_]([a-zA-Z0-9\-_]){0,61})?[a-zA-Z0-9]\.)*' '((([a-zA-Z0-9_]([a-zA-Z0-9\-_]){0,61})?[a-zA-Z0-9]\.)*'
+ '([a-zA-Z0-9_]([a-zA-Z0-9\-_]){0,61})?[a-zA-Z0-9]\.?)' + '([a-zA-Z0-9_]([a-zA-Z0-9\-_]){0,61})?[a-zA-Z0-9]\.?)'
+ '|\.'; + '|\.';
length "1..253"; length "1..253";
} }
} }
leaf-list search { leaf-list search {
type domain-name; type domain-name;
ordered-by user; ordered-by user;
} }
4.3.1. Using SIDs in keys 4.3.1. Using SIDs in Keys
CBOR diagnostic notation: CBOR diagnostic notation:
{ {
1746 : [ "ietf.org", "ieee.org" ] / search (SID 1746) / 1746 : [ "ietf.org", "ieee.org" ] / search (SID 1746) /
} }
CBOR encoding: CBOR encoding:
A1 # map(1) A1 # map(1)
19 06D2 # unsigned(1746) 19 06D2 # unsigned(1746)
82 # array(2) 82 # array(2)
68 # text(8) 68 # text(8)
696574662E6F7267 # "ietf.org" 696574662E6F7267 # "ietf.org"
68 # text(8) 68 # text(8)
696565652E6F7267 # "ieee.org" 696565652E6F7267 # "ieee.org"
4.3.2. Using names in keys 4.3.2. Using Names in Keys
CBOR diagnostic notation: CBOR diagnostic notation:
{ {
"ietf-system:search" : [ "ietf.org", "ieee.org" ] "ietf-system:search" : [ "ietf.org", "ieee.org" ]
} }
CBOR encoding: CBOR encoding:
A1 # map(1) A1 # map(1)
72 # text(18) 72 # text(18)
696574662D73797374656D3A736561726368 # "ietf-system:search" 696574662D73797374656D3A736561726368 # "ietf-system:search"
82 # array(2) 82 # array(2)
68 # text(8) 68 # text(8)
696574662E6F7267 # "ietf.org" 696574662E6F7267 # "ietf.org"
68 # text(8) 68 # text(8)
696565652E6F7267 # "ieee.org" 696565652E6F7267 # "ieee.org"
4.4. The 'list' and 'list' entries 4.4. The 'list' and the 'list' Entries
A list or a subset of a list MUST be encoded using a CBOR array data A list or a subset of a list MUST be encoded using a CBOR array data
item (major type 4). Each list entry within this CBOR array is item (major type 4). Each list entry within this CBOR array is
encoded using a CBOR map data item (major type 5) based on the encoded using a CBOR map data item (major type 5) based on the
encoding rules of a collection as defined in Section 4.2. encoding rules of a container-like instance, as defined in
Section 4.2.
It is important to note that this encoding rule also applies to a It is important to note that this encoding rule also applies to a
'list' representation node instance that has a single entry. 'list' representation node instance that has a single entry.
The following examples show the encoding of a 'server' list using The following examples show the encoding of a 'server' list using
SIDs or names. SIDs or names.
Definition example simplified from [RFC7317]: Definition example adapted from [RFC7317]:
list server { list server {
key name; key name;
leaf name { leaf name {
type string; type string;
} }
choice transport { choice transport {
case udp { case udp {
container udp { container udp {
skipping to change at page 17, line 42 skipping to change at line 796
leaf iburst { leaf iburst {
type boolean; type boolean;
default false; default false;
} }
leaf prefer { leaf prefer {
type boolean; type boolean;
default false; default false;
} }
} }
4.4.1. Using SIDs in keys 4.4.1. Using SIDs in Keys
The encoding rules of each 'list' entry are defined in Section 4.2.1. The encoding rules of each 'list' entry are defined in Section 4.2.1.
CBOR diagnostic notation: CBOR diagnostic notation:
{ {
1756 : [ / server (SID 1756) / 1756 : [ / server (SID 1756) /
{ {
3 : "NRC TIC server", / name (SID 1759) / 3 : "NRC TIC server", / name (SID 1759) /
5 : { / udp (SID 1761) / 5 : { / udp (SID 1761) /
skipping to change at page 19, line 35 skipping to change at line 855
A2 # map(2) A2 # map(2)
03 # unsigned(3) 03 # unsigned(3)
6E # text(14) 6E # text(14)
4E52432054414320736572766572 # "NRC TAC server" 4E52432054414320736572766572 # "NRC TAC server"
05 # unsigned(5) 05 # unsigned(5)
A1 # map(1) A1 # map(1)
01 # unsigned(1) 01 # unsigned(1)
6A # text(10) 6A # text(10)
7461632E6E72632E6361 # "tac.nrc.ca" 7461632E6E72632E6361 # "tac.nrc.ca"
4.4.2. Using names in keys 4.4.2. Using Names in Keys
The encoding rules of each 'list' entry are defined in Section 4.2.2. The encoding rules of each 'list' entry are defined in Section 4.2.2.
CBOR diagnostic notation: CBOR diagnostic notation:
{ {
"ietf-system:server" : [ "ietf-system:server" : [
{ {
"name" : "NRC TIC server", "name" : "NRC TIC server",
"udp" : { "udp" : {
skipping to change at page 21, line 48 skipping to change at line 927
63 # text(3) 63 # text(3)
756470 # "udp" 756470 # "udp"
A1 # map(1) A1 # map(1)
67 # text(7) 67 # text(7)
61646472657373 # "address" 61646472657373 # "address"
6A # text(10) 6A # text(10)
7461632E6E72632E6361 # "tac.nrc.ca" 7461632E6E72632E6361 # "tac.nrc.ca"
4.5. The 'anydata' 4.5. The 'anydata'
An anydata serves as a container for an arbitrary set of An anydata node serves as a container for an arbitrary set of
representation nodes that otherwise appear as normal YANG-modeled representation nodes that otherwise appear as normal YANG-modeled
data. An anydata representation node instance is encoded using the data. An anydata representation node instance is encoded using the
same rules as a container, i.e., CBOR map. The requirement that same rules as a container, i.e., using a CBOR map data item (major
anydata content can be modeled by YANG implies the following: type 5) based on the encoding rules of a container-like instance, as
defined in Section 4.2.
* CBOR map keys of any inner representation nodes MUST be set to
valid deltas or names.
* CBOR arrays MUST contain either unique scalar values (as a leaf-
list, see Section 4.3), or maps (as a list, see Section 4.4).
* CBOR map values MUST follow the encoding rules of one of the
datatypes listed in Section 4.
The following example shows a possible use of an anydata. In this The following example shows a possible use of an anydata node. In
example, an anydata is used to define a representation node this example, an anydata node is used to define a representation node
containing a notification event; this representation node can be part containing a notification event; this representation node can be part
of a YANG list to create an event logger. of a YANG list to create an event logger.
Definition example: Definition example:
module event-log { module event-log {
... ...
anydata last-event; # SID 60123 anydata last-event; // SID 60123
} }
This example also assumes the assistance of the following This example also assumes the assistance of the following
notification. notification.
module example-port { module example-port {
... ...
notification example-port-fault { # SID 60200 notification example-port-fault { // SID 60200
leaf port-name { # SID 60201 leaf port-name { // SID 60201
type string; type string;
} }
leaf port-fault { # SID 60202 leaf port-fault { // SID 60202
type string; type string;
} }
} }
} }
4.5.1. Using SIDs in keys 4.5.1. Using SIDs in Keys
CBOR diagnostic notation: CBOR diagnostic notation:
{ {
60123 : { / last-event (SID 60123) / 60123 : { / last-event (SID 60123) /
77 : { / example-port-fault (SID 60200) / 77 : { / example-port-fault (SID 60200) /
1 : "0/4/21", / port-name (SID 60201) / 1 : "0/4/21", / port-name (SID 60201) /
2 : "Open pin 2" / port-fault (SID 60202) / 2 : "Open pin 2" / port-fault (SID 60202) /
} }
} }
skipping to change at page 23, line 41 skipping to change at line 1002
{ {
60123 : { / last-event (SID 60123) / 60123 : { / last-event (SID 60123) /
47(60200) : { / event-port-fault (SID 60200) / 47(60200) : { / event-port-fault (SID 60200) /
1 : "0/4/21", / port-name (SID 60201) / 1 : "0/4/21", / port-name (SID 60201) /
2 : "Open pin 2" / port-fault (SID 60202) / 2 : "Open pin 2" / port-fault (SID 60202) /
} }
} }
} }
4.5.2. Using names in keys 4.5.2. Using Names in Keys
CBOR diagnostic notation: CBOR diagnostic notation:
{ {
"event-log:last-event" : { "event-log:last-event" : {
"example-port:example-port-fault" : { "example-port:example-port-fault" : {
"port-name" : "0/4/21", "port-name" : "0/4/21",
"port-fault" : "Open pin 2" "port-fault" : "Open pin 2"
} }
} }
skipping to change at page 24, line 32 skipping to change at line 1043
4.6. The 'anyxml' 4.6. The 'anyxml'
An anyxml representation node is used to serialize an arbitrary CBOR An anyxml representation node is used to serialize an arbitrary CBOR
content, i.e., its value can be any CBOR binary object. (The "xml" content, i.e., its value can be any CBOR binary object. (The "xml"
in the name is a misnomer that only applied to YANG-XML [RFC7950].) in the name is a misnomer that only applied to YANG-XML [RFC7950].)
An anyxml value MAY contain CBOR data items tagged with one of the An anyxml value MAY contain CBOR data items tagged with one of the
tags listed in Section 9.3. The tags listed in Section 9.3 SHALL be tags listed in Section 9.3. The tags listed in Section 9.3 SHALL be
supported. supported.
The following example shows a valid CBOR encoded anyxml The following example shows a valid CBOR-encoded anyxml
representation node instance consisting of a CBOR array containing representation node instance consisting of a CBOR array containing
the CBOR simple values 'true', 'null' and 'true'. the CBOR simple values 'true', 'null', and 'true'.
Definition example from [RFC7951]: Definition example adapted from [RFC7951]:
module bar-module { module bar-module {
... ...
anyxml bar; # SID 60000 anyxml bar; // SID 60000
} }
4.6.1. Using SIDs in keys 4.6.1. Using SIDs in Keys
CBOR diagnostic notation: CBOR diagnostic notation:
{ {
60000 : [true, null, true] / bar (SID 60000) / 60000 : [true, null, true] / bar (SID 60000) /
} }
CBOR encoding: CBOR encoding:
A1 # map(1) A1 # map(1)
19 EA60 # unsigned(60000) 19 EA60 # unsigned(60000)
83 # array(3) 83 # array(3)
F5 # primitive(21) F5 # primitive(21)
F6 # primitive(22) F6 # primitive(22)
F5 # primitive(21) F5 # primitive(21)
4.6.2. Using names in keys 4.6.2. Using Names in Keys
CBOR diagnostic notation: CBOR diagnostic notation:
{ {
"bar-module:bar" : [true, null, true] / bar (SID 60000) / "bar-module:bar" : [true, null, true] / bar (SID 60000) /
} }
CBOR encoding: CBOR encoding:
A1 # map(1) A1 # map(1)
6E # text(14) 6E # text(14)
6261722D6D6F64756C653A626172 # "bar-module:bar" 6261722D6D6F64756C653A626172 # "bar-module:bar"
83 # array(3) 83 # array(3)
F5 # primitive(21) F5 # primitive(21)
F6 # primitive(22) F6 # primitive(22)
F5 # primitive(21) F5 # primitive(21)
5. Encoding of 'yang-data' extension 5. Encoding of the 'yang-data' Extension
The yang-data extension [RFC8040] is used to define data structures The yang-data extension [RFC8040] is used to define data structures
in YANG that are not intended to be implemented as part of a in YANG that are not intended to be implemented as part of a
datastore. datastore.
The yang-data extension will specify a container that MUST be encoded The yang-data extension will specify a container that MUST be encoded
using the encoding rules of nodes of data trees as defined in using the encoding rules of nodes of data trees, as defined in
Section 4.2. Section 4.2.
Just like YANG containers, the yang-data extension can be encoded Just like YANG containers, the yang-data extension can be encoded
using either SIDs or names. using either SIDs or names.
Definition example from [I-D.ietf-core-comi] Appendix A: Definition example adapted from Appendix A of [CORE-COMI]:
module ietf-coreconf { module ietf-coreconf {
... ...
import ietf-restconf { import ietf-restconf {
prefix rc; prefix rc;
} }
rc:yang-data yang-errors { rc:yang-data yang-errors {
container error { container error {
skipping to change at page 26, line 34 skipping to change at line 1133
leaf error-data-node { leaf error-data-node {
type instance-identifier; type instance-identifier;
} }
leaf error-message { leaf error-message {
type string; type string;
} }
} }
} }
} }
5.1. Using SIDs in keys 5.1. Using SIDs in Keys
The yang-data extensions encoded using SIDs are carried in a CBOR map The yang-data extensions encoded using SIDs are carried in a CBOR map
containing a single item pair. The key of this item is set to the containing a single item pair. The key of this item is set to the
SID assigned to the yang-data extension container; the value is set SID assigned to the yang-data extension container; the value is set
to the CBOR encoding of this container as defined in Section 4.2. to the CBOR encoding of this container, as defined in Section 4.2.
This example shows a serialization example of the yang-errors yang- This example shows a serialization example of the yang-errors yang-
data extension as defined in [I-D.ietf-core-comi] using SIDs as data extension, as defined in [CORE-COMI], using SIDs, as defined in
defined in Section 3.2. Section 3.2.
CBOR diagnostic notation: CBOR diagnostic notation:
{ {
1024 : { / error (SID 1024) / 1024 : { / error (SID 1024) /
4 : 1011, / error-tag (SID 1028) / 4 : 1011, / error-tag (SID 1028) /
/ = invalid-value (SID 1011) / / = invalid-value (SID 1011) /
1 : 1018, / error-app-tag (SID 1025) / 1 : 1018, / error-app-tag (SID 1025) /
/ = not-in-range (SID 1018) / / = not-in-range (SID 1018) /
2 : 1740, / error-data-node (SID 1026) / 2 : 1740, / error-data-node (SID 1026) /
/ = timezone-utc-offset (SID 1740) / / = timezone-utc-offset (SID 1740) /
3 : "Maximum exceeded" / error-message (SID 1027) / 3 : "Maximum exceeded" / error-message (SID 1027) /
} }
} }
CBOR encoding: CBOR encoding:
A1 # map(1) A1 # map(1)
19 0400 # unsigned(1024) 19 0400 # unsigned(1024)
A4 # map(4) A4 # map(4)
04 # unsigned(4) 04 # unsigned(4)
19 03F3 # unsigned(1011) 19 03F3 # unsigned(1011)
01 # unsigned(1) 01 # unsigned(1)
19 03FA # unsigned(1018) 19 03FA # unsigned(1018)
02 # unsigned(2) 02 # unsigned(2)
19 06CC # unsigned(1740) 19 06CC # unsigned(1740)
03 # unsigned(3) 03 # unsigned(3)
70 # text(16) 70 # text(16)
4D6178696D756D206578636565646564 # "Maximum exceeded" 4D6178696D756D206578636565646564 # "Maximum exceeded"
5.2. Using names in keys 5.2. Using Names in Keys
The yang-data extensions encoded using names are carried in a CBOR The yang-data extensions encoded using names are carried in a CBOR
map containing a single item pair. The key of this item is set to map containing a single item pair. The key of this item is set to
the namespace qualified name of the yang-data extension container; the namespace-qualified name of the yang-data extension container;
the value is set to the CBOR encoding of this container as defined in the value is set to the CBOR encoding of this container, as defined
Section 4.2. in Section 4.2.
This example shows a serialization example of the yang-errors yang- This example shows a serialization example of the yang-errors yang-
data extension as defined in [I-D.ietf-core-comi] using names as data extension, as defined in [CORE-COMI], using names, as defined
defined Section 3.3. Section 3.3.
CBOR diagnostic notation: CBOR diagnostic notation:
{ {
"ietf-coreconf:error" : { "ietf-coreconf:error" : {
"error-tag" : "invalid-value", "error-tag" : "invalid-value",
"error-app-tag" : "not-in-range", "error-app-tag" : "not-in-range",
"error-data-node" : "timezone-utc-offset", "error-data-node" : "timezone-utc-offset",
"error-message" : "Maximum exceeded" "error-message" : "Maximum exceeded"
} }
skipping to change at page 28, line 42 skipping to change at line 1224
# "timezone-utc-offset" # "timezone-utc-offset"
6D # text(13) 6D # text(13)
6572726F722D6D657373616765 # "error-message" 6572726F722D6D657373616765 # "error-message"
70 # text(16) 70 # text(16)
4D6178696D756D206578636565646564 # "Maximum exceeded" 4D6178696D756D206578636565646564 # "Maximum exceeded"
6. Representing YANG Data Types in CBOR 6. Representing YANG Data Types in CBOR
The CBOR encoding of an instance of a leaf or leaf-list The CBOR encoding of an instance of a leaf or leaf-list
representation node depends on the built-in type of that representation node depends on the built-in type of that
representation node. The following sub-section defines the CBOR representation node. The following subsection defines the CBOR
encoding of each built-in type supported by YANG as listed in encoding of each built-in type supported by YANG, as listed in
Section 4.2.4 of [RFC7950]. Each subsection shows an example value Section 4.2.4 of [RFC7950]. Each subsection shows an example value
assigned to a representation node instance of the discussed built-in assigned to a representation node instance of the discussed built-in
type. type.
6.1. The unsigned integer Types 6.1. The Unsigned Integer Types
Leafs of type uint8, uint16, uint32 and uint64 MUST be encoded using Leafs of type uint8, uint16, uint32, and uint64 MUST be encoded using
a CBOR unsigned integer data item (major type 0). a CBOR unsigned integer data item (major type 0).
The following example shows the encoding of an 'mtu' leaf The following example shows the encoding of an 'mtu' leaf
representation node instance set to 1280 bytes. representation node instance set to 1280 bytes.
Definition example from [RFC8344]: Definition example adapted from [RFC8344]:
leaf mtu { leaf mtu {
type uint16 { type uint16 {
range "68..max"; range "68..max";
} }
} }
CBOR diagnostic notation: 1280 CBOR diagnostic notation: 1280
CBOR encoding: 19 0500 CBOR encoding: 19 0500
6.2. The integer Types 6.2. The Integer Types
Leafs of type int8, int16, int32 and int64 MUST be encoded using Leafs of type int8, int16, int32, and int64 MUST be encoded using
either CBOR unsigned integer (major type 0) or CBOR negative integer either a CBOR unsigned integer (major type 0) or a CBOR negative
(major type 1), depending on the actual value. integer (major type 1), depending on the actual value.
The following example shows the encoding of a 'timezone-utc-offset' The following example shows the encoding of a 'timezone-utc-offset'
leaf representation node instance set to -300 minutes. leaf representation node instance set to -300 minutes.
Definition example from [RFC7317]: Definition example adapted from [RFC7317]:
leaf timezone-utc-offset { leaf timezone-utc-offset {
type int16 { type int16 {
range "-1500 .. 1500"; range "-1500 .. 1500";
} }
} }
CBOR diagnostic notation: -300 CBOR diagnostic notation: -300
CBOR encoding: 39 012B CBOR encoding: 39 012B
6.3. The 'decimal64' Type 6.3. The 'decimal64' Type
Leafs of type decimal64 MUST be encoded using a decimal fraction as Leafs of type decimal64 MUST be encoded using a decimal fraction, as
defined in Section 3.4.4 of [RFC8949]. defined in Section 3.4.4 of [RFC8949].
The following example shows the encoding of a 'my-decimal' leaf The following example shows the encoding of a 'my-decimal' leaf
representation node instance set to 2.57. representation node instance set to 2.57.
Definition example from [RFC7317]: Definition example adapted from [RFC7317]:
leaf my-decimal { leaf my-decimal {
type decimal64 { type decimal64 {
fraction-digits 2; fraction-digits 2;
range "1 .. 3.14 | 10 | 20..max"; range "1 .. 3.14 | 10 | 20..max";
} }
} }
CBOR diagnostic notation: 4([-2, 257]) CBOR diagnostic notation: 4([-2, 257])
CBOR encoding: C4 82 21 19 0101 CBOR encoding: C4 82 21 19 0101
6.4. The 'string' Type 6.4. The 'string' Type
Leafs of type string MUST be encoded using a CBOR text string data Leafs of type string MUST be encoded using a CBOR text string data
item (major type 3). item (major type 3).
The following example shows the encoding of a 'name' leaf The following example shows the encoding of a 'name' leaf
representation node instance set to "eth0". representation node instance set to "eth0".
Definition example from [RFC8343]: Definition example adapted from [RFC8343]:
leaf name { leaf name {
type string; type string;
} }
CBOR diagnostic notation: "eth0" CBOR diagnostic notation: "eth0"
CBOR encoding: 64 65746830 CBOR encoding: 64 65746830
6.5. The 'boolean' Type 6.5. The 'boolean' Type
Leafs of type boolean MUST be encoded using a CBOR simple value Leafs of type boolean MUST be encoded using a CBOR simple value
'true' (major type 7, additional information 21) or 'false' (major 'true' (major type 7, additional information 21) or 'false' (major
type 7, additional information 20). type 7, additional information 20).
The following example shows the encoding of an 'enabled' leaf The following example shows the encoding of an 'enabled' leaf
representation node instance set to 'true'. representation node instance set to 'true'.
Definition example from [RFC7317]: Definition example adapted from [RFC7317]:
leaf enabled { leaf enabled {
type boolean; type boolean;
} }
CBOR diagnostic notation: true CBOR diagnostic notation: true
CBOR encoding: F5 CBOR encoding: F5
6.6. The 'enumeration' Type 6.6. The 'enumeration' Type
skipping to change at page 31, line 17 skipping to change at line 1341
Leafs of type enumeration MUST be encoded using a CBOR unsigned Leafs of type enumeration MUST be encoded using a CBOR unsigned
integer (major type 0) or CBOR negative integer (major type 1), integer (major type 0) or CBOR negative integer (major type 1),
depending on the actual value, or exceptionally as a tagged text depending on the actual value, or exceptionally as a tagged text
string (see below). Enumeration values are either explicitly string (see below). Enumeration values are either explicitly
assigned using the YANG statement 'value' or automatically assigned assigned using the YANG statement 'value' or automatically assigned
based on the algorithm defined in Section 9.6.4.2 of [RFC7950]. based on the algorithm defined in Section 9.6.4.2 of [RFC7950].
The following example shows the encoding of an 'oper-status' leaf The following example shows the encoding of an 'oper-status' leaf
representation node instance set to 'testing'. representation node instance set to 'testing'.
Definition example from [RFC7317]: Definition example adapted from [RFC7317]:
leaf oper-status { leaf oper-status {
type enumeration { type enumeration {
enum up { value 1; } enum up { value 1; }
enum down { value 2; } enum down { value 2; }
enum testing { value 3; } enum testing { value 3; }
enum unknown { value 4; } enum unknown { value 4; }
enum dormant { value 5; } enum dormant { value 5; }
enum not-present { value 6; } enum not-present { value 6; }
enum lower-layer-down { value 7; } enum lower-layer-down { value 7; }
skipping to change at page 31, line 39 skipping to change at line 1363
} }
CBOR diagnostic notation: 3 CBOR diagnostic notation: 3
CBOR encoding: 03 CBOR encoding: 03
Values of 'enumeration' types defined in a 'union' type MUST be Values of 'enumeration' types defined in a 'union' type MUST be
encoded using a CBOR text string data item (major type 3) and MUST encoded using a CBOR text string data item (major type 3) and MUST
contain one of the names assigned by 'enum' statements in YANG (see contain one of the names assigned by 'enum' statements in YANG (see
also Section 6.12). The encoding MUST be enclosed by the enumeration also Section 6.12). The encoding MUST be enclosed by the enumeration
CBOR tag as specified in Section 9.3. CBOR tag, as specified in Section 9.3.
Definition example from [RFC7950]: Definition example adapted from [RFC7950]:
type union { type union {
type int32; type int32;
type enumeration { type enumeration {
enum unbounded; enum unbounded;
} }
} }
CBOR diagnostic notation: 44("unbounded") CBOR diagnostic notation: 44("unbounded")
CBOR encoding: D8 2C 69 756E626F756E646564 CBOR encoding: D8 2C 69 756E626F756E646564
6.7. The 'bits' Type 6.7. The 'bits' Type
Keeping in mind that bit positions are either explicitly assigned Keeping in mind that bit positions are either explicitly assigned
using the YANG statement 'position' or automatically assigned based using the YANG statement 'position' or automatically assigned based
on the algorithm defined in Section 9.7.4.2 of [RFC7950], each on the algorithm defined in Section 9.7.4.2 of [RFC7950], each
element of type bits could be seen as a set of bit positions (or element of type bits could be seen as a set of bit positions (or
offsets from position 0), that have a value of either 1, which offsets from position 0) that have a value of either 1, which
represents the bit being set or 0, which represents that the bit is represents the bit being set, or 0, which represents that the bit is
not set. not set.
Leafs of type bits MUST be encoded either using a CBOR array or byte Leafs of type bits MUST be encoded either using a CBOR array (major
string (major type 2), or exceptionally as a tagged text string (see type 4) or byte string (major type 2) or exceptionally as a tagged
below). In case CBOR array representation is used, each element is text string (see below). In case CBOR array representation is used,
either a positive integer (major type 0 with value 0 being each element is either (1) a positive integer (major type 0 with
disallowed) that can be used to calculate the offset of the next byte value 0 being disallowed) that can be used to calculate the offset of
string, or a byte string (major type 2) that carries the information the next byte string or (2) a byte string (major type 2) that carries
whether certain bits are set or not. The initial offset value is 0 the information regarding whether certain bits are set or not. The
and each unsigned integer modifies the offset value of the next byte initial offset value is 0, and each unsigned integer modifies the
string by the integer value multiplied by 8. For example, if the bit offset value of the next byte string by the integer value multiplied
offset is 0 and there is an integer with value 5, the first byte of by 8. For example, if the bit offset is 0 and there is an integer
the byte string that follows will represent bit positions 40 to 47 with value 5, the first byte of the byte string that follows will
both ends included. If the byte string has a second byte, it will represent bit positions 40 to 47, with both ends included. If the
carry information about bits 48 to 55 and so on. Within each byte, byte string has a second byte, it will carry information about bits
bits are assigned from least to most significant. After the byte 48 to 55, and so on. Within each byte, bits are assigned from least
string, the offset is modified by the number of bytes in the byte to most significant. After the byte string, the offset is modified
string multiplied by 8. Bytes with no bits set (zero bytes) at the by the number of bytes in the byte string multiplied by 8. Bytes
end of the byte string are never generated: If they would occur at with no bits set (zero bytes) at the end of the byte string are never
the end of the array, the zero bytes are simply omitted; if they generated. If they occur at the end of the array, the zero bytes are
occur at the end of a byte string preceding an integer, the zero simply omitted; if they occur at the end of a byte string preceding
bytes are removed and the integer adjusted upwards by the number of an integer, the zero bytes are removed and the integer is adjusted
zero bytes removed. An example follows. upwards by the number of zero bytes that were removed. An example
follows.
The following example shows the encoding of an 'alarm-state' leaf The following example shows the encoding of an 'alarm-state' leaf
representation node instance with the 'critical' (position 2), representation node instance with the 'critical' (position 2),
'warning' (position 8) and 'indeterminate' (position 128) flags set. 'warning' (position 8), and 'indeterminate' (position 128) flags set.
typedef alarm-state { typedef alarm-state {
type bits { type bits {
bit unknown; bit unknown;
bit under-repair; bit under-repair;
bit critical; bit critical;
bit major; bit major;
bit minor; bit minor;
bit warning { bit warning {
position 8; position 8;
skipping to change at page 33, line 29 skipping to change at line 1439
} }
leaf alarm-state { leaf alarm-state {
type alarm-state; type alarm-state;
} }
CBOR diagnostic notation: [h'0401', 14, h'01'] CBOR diagnostic notation: [h'0401', 14, h'01']
CBOR encoding: 83 42 0401 0E 41 01 CBOR encoding: 83 42 0401 0E 41 01
In a number of cases the array would only need to have one element -- In a number of cases, the array would only need to have one element
a byte string with a few bytes inside. For this case, it is REQUIRED -- a byte string with a few bytes inside. For this case, it is
to omit the array element and have only the byte array that would REQUIRED to omit the array element and have only the byte array that
have been inside. To illustrate this, let us consider the same would have been inside. To illustrate this, let us consider the same
example YANG definition, but this time encoding only 'under-repair' example YANG definition but this time encoding only 'under-repair'
and 'critical' flags. The result would be and 'critical' flags. The result would be
CBOR diagnostic notation: h'06' CBOR diagnostic notation: h'06'
CBOR encoding: 41 06 CBOR encoding: 41 06
Elements in the array MUST be either byte strings that do not end in Elements in the array MUST be either byte strings that do not end in
a zero byte, or positive unsigned integers, where byte strings and a zero byte or positive unsigned integers, where byte strings and
integers MUST alternate, i.e., adjacent byte strings or adjacent integers MUST alternate, i.e., adjacent byte strings or adjacent
integers are an error. An array with a single byte string MUST integers are an error. An array with a single byte string MUST
instead be encoded as just that byte string. An array with a single instead be encoded as just that byte string. An array with a single
positive integer is an error. Note that a recipient can handle positive integer is an error. Note that a recipient can handle
trailing zero bytes in the byte strings using the normal rules trailing zero bytes in the byte strings using the normal rules
without any issue, so an implementation MAY silently accept them. without any issue, so an implementation MAY silently accept them.
Values of 'bits' types defined in a 'union' type MUST be encoded Values of 'bits' types defined in a 'union' type MUST be encoded
using a CBOR text string data item (major type 3) and MUST contain a using a CBOR text string data item (major type 3) and MUST contain a
space-separated sequence of names of 'bits' that are set (see also space-separated sequence of names of 'bits' that are set (see also
Section 6.12). The encoding MUST be enclosed by the bits CBOR tag as Section 6.12). The encoding MUST be enclosed by the bits CBOR tag,
specified in Section 9.3. as specified in Section 9.3.
The following example shows the encoding of an 'alarm-state' leaf The following example shows the encoding of an 'alarm-state' leaf
representation node instance defined using a union type with the representation node instance defined using a union type with the
'under-repair' and 'critical' flags set. 'under-repair' and 'critical' flags set.
Definition example: Definition example:
leaf alarm-state-2 { leaf alarm-state-2 {
type union { type union {
type alarm-state; type alarm-state;
skipping to change at page 35, line 13 skipping to change at line 1513
CBOR encoding: 50 1F1CE6A3F42660D888D92A4D8030476E CBOR encoding: 50 1F1CE6A3F42660D888D92A4D8030476E
6.9. The 'leafref' Type 6.9. The 'leafref' Type
Leafs of type leafref MUST be encoded using the rules of the Leafs of type leafref MUST be encoded using the rules of the
representation node referenced by the 'path' YANG statement. representation node referenced by the 'path' YANG statement.
The following example shows the encoding of an 'interface-state-ref' The following example shows the encoding of an 'interface-state-ref'
leaf representation node instance set to "eth1". leaf representation node instance set to "eth1".
Definition example from [RFC8343]: Definition example adapted from [RFC8343]:
typedef interface-state-ref { typedef interface-state-ref {
type leafref { type leafref {
path "/interfaces-state/interface/name"; path "/interfaces-state/interface/name";
} }
} }
container interfaces-state { container interfaces-state {
list interface { list interface {
key "name"; key "name";
skipping to change at page 35, line 40 skipping to change at line 1540
} }
} }
CBOR diagnostic notation: "eth1" CBOR diagnostic notation: "eth1"
CBOR encoding: 64 65746831 CBOR encoding: 64 65746831
6.10. The 'identityref' Type 6.10. The 'identityref' Type
This specification supports two approaches for encoding identityref: This specification supports two approaches for encoding identityref:
as a YANG Schema Item iDentifier as defined in Section 3.2, or as a as a YANG Schema Item iDentifier, as defined in Section 3.2, or as a
name as defined in Section 6.8 of [RFC7951]. See Section 6.12 for an name, as defined in Section 6.8 of [RFC7951]. See Section 6.12 for
exceptional case when this representation needs to be tagged. an exceptional case when this representation needs to be tagged.
6.10.1. SIDs as identityref 6.10.1. SIDs as 'identityref'
When representation nodes of type identityref are implemented using When representation nodes of type identityref are implemented using
SIDs, they MUST be encoded using a CBOR unsigned integer data item SIDs, they MUST be encoded using a CBOR unsigned integer data item
(major type 0). (Note that, as they are not used in the position of (major type 0). (Note that, as they are not used in the position of
CBOR map keys, no delta mechanism is employed for SIDs used for CBOR map keys, no delta mechanism is employed for SIDs used for
identityref.) identityref.)
The following example shows the encoding of a 'type' leaf The following example shows the encoding of a 'type' leaf
representation node instance set to the value 'iana-if- representation node instance set to the value 'iana-if-
type:ethernetCsmacd' (SID 1880). type:ethernetCsmacd' (SID 1880).
Definition example from [RFC7317]: Definition example adapted from [RFC7317]:
identity interface-type { identity interface-type {
} }
identity iana-interface-type { identity iana-interface-type {
base interface-type; base interface-type;
} }
identity ethernetCsmacd { identity ethernetCsmacd {
base iana-interface-type; base iana-interface-type;
skipping to change at page 36, line 31 skipping to change at line 1579
leaf type { leaf type {
type identityref { type identityref {
base interface-type; base interface-type;
} }
} }
CBOR diagnostic notation: 1880 CBOR diagnostic notation: 1880
CBOR encoding: 19 0758 CBOR encoding: 19 0758
6.10.2. Name as identityref 6.10.2. Name as 'identityref'
Alternatively, an identityref MAY be encoded using a name as defined Alternatively, an identityref MAY be encoded using a name, as defined
in Section 3.3. When names are used, identityref MUST be encoded in Section 3.3. When names are used, identityref MUST be encoded
using a CBOR text string data item (major type 3). If the identity using a CBOR text string data item (major type 3). If the identity
is defined in different module than the leaf node containing the is defined in a different module than the leaf node containing the
identityref data node, the namespace qualified form MUST be used. identityref data node, the namespace-qualified form MUST be used.
Otherwise, both the simple and namespace qualified forms are Otherwise, both the simple and namespace-qualified forms are
permitted. Names and namespaces are defined in Section 3.3. permitted. Names and namespaces are defined in Section 3.3.
The following example shows the encoding of the identity 'iana-if- The following example shows the encoding of the identity 'iana-if-
type:ethernetCsmacd' using its namespace qualified name. This type:ethernetCsmacd' using its namespace-qualified name. This
example is described in Section 6.10.1. example is described in Section 6.10.1.
CBOR diagnostic notation: "iana-if-type:ethernetCsmacd" CBOR diagnostic notation: "iana-if-type:ethernetCsmacd"
CBOR encoding: 78 1b CBOR encoding: 78 1B
69616E612D69662D747970653A65746865726E657443736D616364 69616E612D69662D747970653A65746865726E657443736D616364
6.11. The 'empty' Type 6.11. The 'empty' Type
Leafs of type empty MUST be encoded using the CBOR null value (major Leafs of type empty MUST be encoded using the CBOR null value (major
type 7, additional information 22). type 7, additional information 22).
The following example shows the encoding of an 'is-router' leaf The following example shows the encoding of an 'is-router' leaf
representation node instance when present. representation node instance when present.
Definition example from [RFC8344]: Definition example adapted from [RFC8344]:
leaf is-router { leaf is-router {
type empty; type empty;
} }
CBOR diagnostic notation: null CBOR diagnostic notation: null
CBOR encoding: F6 CBOR encoding: F6
6.12. The 'union' Type 6.12. The 'union' Type
skipping to change at page 37, line 40 skipping to change at line 1633
* bits * bits
* enumeration * enumeration
* identityref * identityref
* instance-identifier * instance-identifier
See Section 9.3 for the assigned value of these CBOR tags. See Section 9.3 for the assigned value of these CBOR tags.
As mentioned in Section 6.6 and in Section 6.7, 'enumeration' and As mentioned in Sections 6.6 and in 6.7, 'enumeration' and 'bits' are
'bits' are encoded as a CBOR text string data item (major type 3) encoded as a CBOR text string data item (major type 3) when defined
when defined within a 'union' type. (This adds considerable within a 'union' type. (This adds considerable complexity but is
complexity, but is necessary because of an idiosyncrasy of the YANG necessary because of an idiosyncrasy of the YANG data model for
data model for unions; the workaround allows compatibility to be unions; the work-around allows compatibility to be maintained with
maintained with the encoding of overlapping unions in XML and JSON. the encoding of overlapping unions in XML and JSON. See also
See also Section 9.12 of [RFC7950].) Section 9.12 of [RFC7950].)
The following example shows the encoding of an 'ip-address' leaf The following example shows the encoding of an 'ip-address' leaf
representation node instance when set to "2001:db8:a0b:12f0::1". representation node instance when set to "2001:db8:a0b:12f0::1".
Definition example (adapted from [RFC6991]): Definition example adapted from [RFC6991]:
typedef ipv4-address { typedef ipv4-address {
type string { type string {
pattern pattern
'(([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])\.){3}' '(([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])\.){3}'
+ '([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])' + '([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])'
+ '(%[\p{N}\p{L}]+)?'; + '(%[\p{N}\p{L}]+)?';
} }
} }
skipping to change at page 38, line 45 skipping to change at line 1686
type ip-address; type ip-address;
} }
CBOR diagnostic notation: "2001:db8:a0b:12f0::1" CBOR diagnostic notation: "2001:db8:a0b:12f0::1"
CBOR encoding: 74 323030313A6462383A6130623A313266303A3A31 CBOR encoding: 74 323030313A6462383A6130623A313266303A3A31
6.13. The 'instance-identifier' Type 6.13. The 'instance-identifier' Type
This specification supports two approaches for encoding an instance- This specification supports two approaches for encoding an instance-
identifier, one based on YANG Schema Item iDentifier as defined in identifier: one based on YANG Schema Item iDentifier, as defined in
Section 3.2 and one based on names as defined in Section 3.3. See Section 3.2, and one based on names, as defined in Section 3.3. See
Section 6.12 for an exceptional case when this representation needs Section 6.12 for an exceptional case when this representation needs
to be tagged. to be tagged.
6.13.1. SIDs as instance-identifier 6.13.1. SIDs as 'instance-identifier'
SIDs uniquely identify a schema node. In the case of a single SIDs uniquely identify a schema node. In the case of a single
instance schema node, i.e., a schema node defined at the root of a instance schema node, i.e., a schema node defined at the root of a
YANG module or submodule or schema nodes defined within a container, YANG module or submodule or schema nodes defined within a container,
the SID is sufficient to identify this instance (representation the SID is sufficient to identify this instance (representation
node). (Note that no delta mechanism is employed for SIDs used for node). (Note that no delta mechanism is employed for SIDs used for
identityref, see Section 6.10.1.) identityref, see Section 6.10.1.)
In the case of a representation node that is an entry of a YANG list, In the case of a representation node that is an entry of a YANG list,
a SID is combined with the list key(s) to identify each instance a SID is combined with the list key(s) to identify each instance
within the YANG list(s). within the YANG list(s).
Instance identifiers of single instance schema nodes MUST be encoded Instance-identifiers of single instance schema nodes MUST be encoded
using a CBOR unsigned integer data item (major type 0) and set to the using a CBOR unsigned integer data item (major type 0) and set to the
targeted schema node SID. targeted schema node SID.
Instance identifiers of representation node entries of a YANG list Instance-identifiers of representation node entries of a YANG list
MUST be encoded using a CBOR array data item (major type 4) MUST be encoded using a CBOR array data item (major type 4)
containing the following entries: containing the following entries:
* The first entry MUST be encoded as a CBOR unsigned integer data * The first entry MUST be encoded as a CBOR unsigned integer data
item (major type 0) and set to the targeted schema node SID. item (major type 0) and set to the targeted schema node SID.
* The following entries MUST contain the value of each key required * The following entries MUST contain the value of each key required
to identify the instance of the targeted schema node. These keys to identify the instance of the targeted schema node. These keys
MUST be ordered as defined in the 'key' YANG statement, starting MUST be ordered as defined in the 'key' YANG statement, starting
from the top level list, and followed by each of the subordinate from the top-level list, and followed by each subordinate list(s).
list(s).
Examples within this section assume the definition of a schema node Examples within this section assume the definition of a schema node
of type 'instance-identifier': of type 'instance-identifier':
Definition example from [RFC7950]: Definition example adapted from [RFC7950]:
container system { container system {
... ...
leaf reporting-entity { leaf reporting-entity {
type instance-identifier; type instance-identifier;
} }
*First example:* *First example:*
The following example shows the encoding of the 'reporting-entity' The following example shows the encoding of the 'reporting-entity'
value referencing data node instance "/system/contact" (SID 1741). value referencing data node instance "/system/contact" (SID 1741).
Definition example from [RFC7317]: Definition example adapted from [RFC7317]:
container system { container system {
leaf contact { leaf contact {
type string; type string;
} }
leaf hostname { leaf hostname {
type inet:domain-name; type inet:domain-name;
} }
skipping to change at page 42, line 4 skipping to change at line 1812
84 # array(4) 84 # array(4)
19 06C6 # unsigned(1734) 19 06C6 # unsigned(1734)
63 # text(3) 63 # text(3)
626F62 # "bob" 626F62 # "bob"
65 # text(5) 65 # text(5)
61646D696E # "admin" 61646D696E # "admin"
66 # text(6) 66 # text(6)
6672616E6365 # "france" 6672616E6365 # "france"
*Third example:* *Third example:*
The following example shows the encoding of the 'reporting-entity' The following example shows the encoding of the 'reporting-entity'
value referencing the list instance "/system/authentication/user" value referencing the list instance "/system/authentication/user"
(SID 1730) corresponding to username "jack". (SID 1730), corresponding to username "jack".
CBOR diagnostic notation: [1730, "jack"] CBOR diagnostic notation: [1730, "jack"]
CBOR encoding: CBOR encoding:
82 # array(2) 82 # array(2)
19 06C2 # unsigned(1730) 19 06C2 # unsigned(1730)
64 # text(4) 64 # text(4)
6A61636B # "jack" 6A61636B # "jack"
6.13.2. Names as instance-identifier 6.13.2. Names as 'instance-identifier'
An "instance-identifier" value is encoded as a text string that is An 'instance-identifier' value is encoded as a text string that is
analogous to the lexical representation in XML encoding; see analogous to the lexical representation in XML encoding; see
Section 9.13.2 of [RFC7950]. However, the encoding of namespaces in Section 9.13.2 of [RFC7950]. However, the encoding of namespaces in
instance-identifier values follows the rules stated in Section 3.3, instance-identifier values follows the rules stated in Section 3.3,
namely: namely:
* The leftmost (top-level) data node name is always in the namespace * The leftmost (top-level) data node name is always in the
qualified form. namespace-qualified form.
* Any subsequent data node name is in the namespace qualified form * Any subsequent data node name is in the namespace-qualified form
if the node is defined in a module other than its parent node, and if the node is defined in a module other than its parent node;
the simple form is used otherwise. This rule also holds for node otherwise, the simple form is used. This rule also holds for node
names appearing in predicates. names appearing in predicates.
For example, For example,
/ietf-interfaces:interfaces/interface[name='eth0']/ietf-ip:ipv4/ip /ietf-interfaces:interfaces/interface[name='eth0']/ietf-ip:ipv4/ip
is a valid instance-identifier value because the data nodes is a valid instance-identifier value because the data nodes
"interfaces", "interface", and "name" are defined in the module "interfaces", "interface", and "name" are defined in the module
"ietf-interfaces", whereas "ipv4" and "ip" are defined in "ietf-ip". "ietf-interfaces", whereas "ipv4" and "ip" are defined in "ietf-ip".
The resulting xpath MUST be encoded using a CBOR text string data The resulting XML Path Language (XPath) MUST be encoded using a CBOR
item (major type 3). text string data item (major type 3).
*First example:* *First example:*
This example is described in Section 6.13.1. This example is described in Section 6.13.1.
CBOR diagnostic notation: "/ietf-system:system/contact" CBOR diagnostic notation: "/ietf-system:system/contact"
CBOR encoding: CBOR encoding:
78 1c 2F696574662D73797374656D3A73797374656D2F636F6E74616374 78 1B 2F696574662D73797374656D3A73797374656D2F636F6E74616374
*Second example:* *Second example:*
This example is described in Section 6.13.1. This example is described in Section 6.13.1.
CBOR diagnostic notation (the line break is inserted for exposition CBOR diagnostic notation (the line break is inserted for exposition
only): only):
"/ietf-system:system/authentication/user[name='bob']/ "/ietf-system:system/authentication/user[name='bob']/
authorized-key[name='admin'][country='france']/key-data" authorized-key[name='admin'][country='france']/key-data"
skipping to change at page 43, line 41 skipping to change at line 1897
"/ietf-system:system/authentication/user[name='jack']" "/ietf-system:system/authentication/user[name='jack']"
CBOR encoding: CBOR encoding:
78 34 # text(52) 78 34 # text(52)
2F696574662D73797374656D3A73797374656D2F61757468656E74696361 2F696574662D73797374656D3A73797374656D2F61757468656E74696361
74696F6E2F757365725B6E616D653D276A61636B275D 74696F6E2F757365725B6E616D653D276A61636B275D
7. Content-Types 7. Content-Types
This specification defines the media-type application/yang-data+cbor, This specification defines the media type application/yang-data+cbor,
which can be used without parameters or with the id parameter set to which can be used without parameters or with the id parameter set to
either name or sid. either name or sid.
This media-type represents a YANG-CBOR document containing a This media type represents a YANG-CBOR document containing a
representation tree. If the media-type parameter id is present, representation tree. If the media type parameter id is present,
depending on its value, each representation node is identified by its depending on its value, each representation node is identified by its
associated namespace qualified name as defined in Section 3.3 associated namespace-qualified name, as defined in Section 3.3
(id=name), or by its associated YANG SID (represented, e.g., in CBOR (id=name), or by its associated YANG SID (represented, e.g., in CBOR
map keys as a SID delta or via tag number 47) as defined in map keys as a SID delta or via tag number 47), as defined in
Section 3.2 (id=sid), respectively. If no id parameter is given, Section 3.2 (id=sid), respectively. If no id parameter is given,
both forms may be present. both forms may be present.
The format of an application/yang-data+cbor representation is that of The format of an application/yang-data+cbor representation is that of
a CBOR map, mapping names and/or SIDs (as defined above) into a CBOR map, mapping names, and/or SIDs (as defined above) into
instance values (using the rules defined in Section 4). instance values (using the rules defined in Section 4).
It is not foreseen at this point that the valid set of values for the It is not foreseen at this point that the valid set of values for the
id parameter will extend beyond name, sid, or being unset; if that id parameter will extend beyond name, sid, or being unset; if that
does happen, any new value is foreseen to be of the form does happen, any new value is foreseen to be of the form
[a-z][a-z0-9]*(-[a-z0-9]+)*. [a-z][a-z0-9]*(-[a-z0-9]+)*.
In summary, this document defines three content-types, which are In summary, this document defines three content-types, which are
intended for use by different classes of applications: intended for use by different classes of applications:
* application/yang-data+cbor; id=sid -- for use by applications that * application/yang-data+cbor; id=sid -- for use by applications that
need to be frugal with encoding space and text string processing need to be frugal with encoding space and text string processing
(e.g., applications running on constrained nodes [RFC7228], or (e.g., applications running on constrained nodes [RFC7228] or
applications with particular performance requirements); applications with particular performance requirements);
* application/yang-data+cbor; id=name -- for use by applications * application/yang-data+cbor; id=name -- for use by applications
that do not want to engage in SID management, and that have ample that do not want to engage in SID management and that have ample
resources to manage text-string based item identifiers (e.g., resources to manage text-string-based item identifiers (e.g.,
applications that directly want to substitute application/ applications that directly want to substitute application/
yang.data+json with a more efficient representation without any yang.data+json with a more efficient representation without any
other changes); other changes); and
* application/yang-data+cbor -- for use by more complex applications * application/yang-data+cbor -- for use by more complex applications
that can benefit from the increased efficiency of SID identifiers that can benefit from the increased efficiency of SID identifiers
but also need to integrate databases of YANG modules before SID but also need to integrate databases of YANG modules before SID
mappings are defined for them. mappings are defined for them.
All three content-types are based on the same representation All three content-types are based on the same representation
mechanisms, parts of which are simply not used in the first and mechanisms, parts of which are simply not used in the first and
second case. second cases.
How the use of one of these content types is selected in a transfer How the use of one of these content-types is selected in a transfer
protocol is outside the scope of this specification. The last protocol is outside the scope of this specification. The last
paragraph of Section 5.2 of [RFC8040] discusses how to indicate and paragraph of Section 5.2 of [RFC8040] discusses how to indicate and
request the usage of specific content-types in RESTCONF. Similar request the usage of specific content-types in RESTCONF. Similar
mechanisms are available in CoAP [RFC7252] using the Content-Format mechanisms are available in the Constrained Application Protocol
and Accept Options; [I-D.ietf-core-comi] demonstrates specifics on (CoAP) [RFC7252] using the Content-Format and Accept Options;
how Content-Format may be used to indicate the id=sid case. [CORE-COMI] demonstrates specifics on how Content-Format may be used
to indicate the id=sid case.
8. Security Considerations 8. Security Considerations
The security considerations of [RFC8949] and [RFC7950] apply. The security considerations of [RFC8949] and [RFC7950] apply.
This document defines an alternative encoding for data modeled in the This document defines an alternative encoding for data modeled in the
YANG data modeling language. As such, this encoding does not YANG data modeling language. As such, this encoding does not
contribute any new security issues in addition to those identified contribute any new security issues in addition to those identified
for the specific protocol or context for which it is used. for the specific protocol or context for which it is used.
To minimize security risks, software on the receiving side SHOULD To minimize security risks, software on the receiving side SHOULD
reject all messages that do not comply to the rules of this document reject all messages that do not comply to the rules of this document
and reply with an appropriate error message to the sender. and reply with an appropriate error message to the sender.
For instance, when the 'id' parameter to the media type is used, it For instance, when the id parameter to the media type is used, it is
is important to properly reject identifiers of the other type, to important to properly reject identifiers of the other type to avoid
avoid scenarios where different implementations interpret a given scenarios where different implementations interpret a given content
content in different ways. in different ways.
When SIDs are in use, the interpretation of encoded data not only When SIDs are in use, the interpretation of encoded data not only
relies on having the right YANG modules, but also on having the right relies on having the right YANG modules but also on having the right
SID mapping information. Management and evolution of that mapping SID mapping information. Management and evolution of that mapping
information therefore requires the same care as the management and information therefore requires the same care as the management and
evolution of the YANG modules themselves. The procedures in evolution of the YANG modules themselves. The procedures in
[I-D.ietf-core-sid] are being defined with this in mind. [CORE-SID] are being defined with this in mind.
9. IANA Considerations 9. IANA Considerations
9.1. Media-Types Registry 9.1. Media Types Registry
This document adds the following Media-Type to the "Media Types" IANA has added the following media type to the "Media Types" registry
registry. [IANA.media-types].
+================+============================+===========+ +================+============================+===========+
| Name | Template | Reference | | Name | Template | Reference |
+================+============================+===========+ +================+============================+===========+
| yang-data+cbor | application/yang-data+cbor | RFC XXXX | | yang-data+cbor | application/yang-data+cbor | RFC 9254 |
+----------------+----------------------------+-----------+ +----------------+----------------------------+-----------+
Table 2 Table 2: Media Types Registry
// RFC Ed.: please replace RFC XXXX with this RFC number and remove
this note.
Type name: application Type name: application
Subtype name: yang-data+cbor Subtype name: yang-data+cbor
Required parameters: N/A Required parameters: N/A
Optional parameters: id (see Section 7 of RFC XXXX)
Optional parameters: id (see Section 7 of RFC 9254)
Encoding considerations: binary (CBOR) Encoding considerations: binary (CBOR)
Security considerations: see Section 8 of RFC XXXX
Published specification: RFC XXXX Security considerations: see Section 8 of RFC 9254
Interoperability considerations: N/A
Published specification: RFC 9254
Applications that use this media type: applications that need a
concise and efficient representation of YANG-modeled data
Fragment identifier considerations: The syntax and semantics of
fragment identifiers specified for "application/yang-data+cbor" is
as specified for "application/cbor". (At publication of this
document, there is no fragment identification syntax defined for
"application/cbor".)
Additional information:
Magic number(s): N/A
File extension(s): N/A
Macintosh file type code(s): N/A
Person & email address to contact for further information: CORE WG Person & email address to contact for further information: CORE WG
mailing list (core@ietf.org), or IETF Applications and Real-Time mailing list (core@ietf.org) or IETF Applications and Real-Time
Area (art@ietf.org) Area (art@ietf.org)
Intended usage: COMMON Intended usage: COMMON
Restrictions on usage: none
Author/Change controller: IETF
9.2. CoAP Content-Formats Registry Restrictions on usage: N/A
This document adds the following Content-Format to the "CoAP Content- Author: CoRE WG
Formats", within the "Constrained RESTful Environments (CoRE)
Parameters" registry, where TBD3 comes from the "Expert Review" 0-255
range and TBD1 and TBD2 come from the "IETF Review" 256-9999 range.
+============================+================+======+===========+ Change controller: IETF
| Content Type | Content Coding | ID | Reference |
+============================+================+======+===========+
| application/yang-data+cbor | - | TBD1 | RFC XXXX |
+----------------------------+----------------+------+-----------+
| application/yang- | - | TBD2 | RFC XXXX |
| data+cbor; id=name | | | |
+----------------------------+----------------+------+-----------+
| application/yang- | - | TBD3 | RFC XXXX |
| data+cbor; id=sid | | | |
+----------------------------+----------------+------+-----------+
Table 3 9.2. CoAP Content-Formats Registry
// RFC Ed.: please replace TBDx with assigned IDs, remove the IANA has added the following Content-Formats to the "CoAP
requested ranges, and remove this note. Content-Formats" subregistry, within the "Constrained RESTful
// RFC Ed.: please replace RFC XXXX with this RFC number and remove Environments (CoRE) Parameters" registry [IANA.core-parameters]. The
this note. registration procedure is "Expert Review" for the 0-255 range and
"IETF Review" for the 256-9999 range.
+=====================================+==========+=====+===========+
| Media Type | Encoding | ID | Reference |
+=====================================+==========+=====+===========+
| application/yang-data+cbor | - | 340 | RFC 9254 |
+-------------------------------------+----------+-----+-----------+
| application/yang-data+cbor; id=name | - | 341 | RFC 9254 |
+-------------------------------------+----------+-----+-----------+
| application/yang-data+cbor; id=sid | - | 140 | RFC 9254 |
+-------------------------------------+----------+-----+-----------+
Table 3: CoAP Content-Format Registry
9.3. CBOR Tags Registry 9.3. CBOR Tags Registry
In the registry "CBOR Tags" [IANA.cbor-tags], as per Section 9.2 of IANA has allocated the following CBOR tag numbers in the "CBOR Tags"
[RFC8949], IANA has allocated the CBOR tags in Table 4 for the YANG registry [IANA.cbor-tags] defined in Section 9.2 of [RFC8949].
datatypes listed.
+=====+==================+============================+===========+ +=====+==================+============================+===========+
| Tag | Data Item | Semantics | Reference | | Tag | Data Item | Semantics | Reference |
+=====+==================+============================+===========+ +=====+==================+============================+===========+
| 43 | text string | YANG bits datatype; see | RFC XXXX | | 43 | text string | YANG bits datatype; see | RFC 9254 |
| | | Section 6.7 | | | | | Section 6.7. | |
+-----+------------------+----------------------------+-----------+ +-----+------------------+----------------------------+-----------+
| 44 | text string | YANG enumeration datatype; | RFC XXXX | | 44 | text string | YANG enumeration datatype; | RFC 9254 |
| | | see Section 6.6. | | | | | see Section 6.6. | |
+-----+------------------+----------------------------+-----------+ +-----+------------------+----------------------------+-----------+
| 45 | unsigned integer | YANG identityref datatype; | RFC XXXX | | 45 | unsigned integer | YANG identityref datatype; | RFC 9254 |
| | or text string | see Section 6.10. | | | | or text string | see Section 6.10. | |
+-----+------------------+----------------------------+-----------+ +-----+------------------+----------------------------+-----------+
| 46 | unsigned integer | YANG instance-identifier | RFC XXXX | | 46 | unsigned integer | YANG instance-identifier | RFC 9254 |
| | or text string | datatype; see | | | | or text string | datatype; see | |
| | or array | Section 6.13. | | | | or array | Section 6.13. | |
+-----+------------------+----------------------------+-----------+ +-----+------------------+----------------------------+-----------+
| 47 | unsigned integer | YANG Schema Item | RFC XXXX | | 47 | unsigned integer | YANG Schema Item | RFC 9254 |
| | | iDentifier (SID); see | | | | | iDentifier (SID); see | |
| | | Section 3.2. | | | | | Section 3.2. | |
+-----+------------------+----------------------------+-----------+ +-----+------------------+----------------------------+-----------+
Table 4: CBOR tags defined by this specification Table 4: CBOR Tags Registry
// RFC Ed.: please replace RFC XXXX with RFC number and remove this
note
10. References 10. References
10.1. Normative References 10.1. Normative References
[IANA.cbor-tags] [IANA.cbor-tags]
IANA, "Concise Binary Object Representation (CBOR) Tags", IANA, "Concise Binary Object Representation (CBOR) Tags",
<https://www.iana.org/assignments/cbor-tags>. <https://www.iana.org/assignments/cbor-tags>.
[IANA.core-parameters]
IANA, "Constrained RESTful Environments (CoRE)
Parameters",
<https://www.iana.org/assignments/core-parameters/>.
[IANA.media-types]
IANA, "Media Types",
<https://www.iana.org/assignments/media-types/>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997, DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>. <https://www.rfc-editor.org/info/rfc2119>.
[RFC5234] Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax [RFC5234] Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax
Specifications: ABNF", STD 68, RFC 5234, Specifications: ABNF", STD 68, RFC 5234,
DOI 10.17487/RFC5234, January 2008, DOI 10.17487/RFC5234, January 2008,
<https://www.rfc-editor.org/info/rfc5234>. <https://www.rfc-editor.org/info/rfc5234>.
skipping to change at page 48, line 39 skipping to change at line 2150
Structure Extensions", RFC 8791, DOI 10.17487/RFC8791, Structure Extensions", RFC 8791, DOI 10.17487/RFC8791,
June 2020, <https://www.rfc-editor.org/info/rfc8791>. June 2020, <https://www.rfc-editor.org/info/rfc8791>.
[RFC8949] Bormann, C. and P. Hoffman, "Concise Binary Object [RFC8949] Bormann, C. and P. Hoffman, "Concise Binary Object
Representation (CBOR)", STD 94, RFC 8949, Representation (CBOR)", STD 94, RFC 8949,
DOI 10.17487/RFC8949, December 2020, DOI 10.17487/RFC8949, December 2020,
<https://www.rfc-editor.org/info/rfc8949>. <https://www.rfc-editor.org/info/rfc8949>.
10.2. Informative References 10.2. Informative References
[I-D.ietf-core-comi] [CORE-COMI]
Veillette, M., Stok, P. V. D., Pelov, A., Bierman, A., and Veillette, M., Ed., van der Stok, P., Ed., Pelov, A.,
I. Petrov, "CoAP Management Interface (CORECONF)", Work in Bierman, A., and I. Petrov, Ed., "CoAP Management
Progress, Internet-Draft, draft-ietf-core-comi-11, 17 Interface (CORECONF)", Work in Progress, Internet-Draft,
January 2021, <https://www.ietf.org/archive/id/draft-ietf- draft-ietf-core-comi-11, 17 January 2021,
core-comi-11.txt>. <https://datatracker.ietf.org/doc/html/draft-ietf-core-
comi-11>.
[I-D.ietf-core-sid] [CORE-SID] Veillette, M., Ed., Pelov, A., Ed., Petrov, I., Ed.,
Veillette, M., Pelov, A., Petrov, I., Bormann, C., and M. Bormann, C., and M. Richardson, "YANG Schema Item
Richardson, "YANG Schema Item iDentifier (YANG SID)", Work iDentifier (YANG SID)", Work in Progress, Internet-Draft,
in Progress, Internet-Draft, draft-ietf-core-sid-18, 18 draft-ietf-core-sid-18, 18 November 2021,
November 2021, <https://www.ietf.org/archive/id/draft- <https://datatracker.ietf.org/doc/html/draft-ietf-core-
ietf-core-sid-18.txt>. sid-18>.
[RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed., [RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
and A. Bierman, Ed., "Network Configuration Protocol and A. Bierman, Ed., "Network Configuration Protocol
(NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011, (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011,
<https://www.rfc-editor.org/info/rfc6241>. <https://www.rfc-editor.org/info/rfc6241>.
[RFC6991] Schoenwaelder, J., Ed., "Common YANG Data Types", [RFC6991] Schoenwaelder, J., Ed., "Common YANG Data Types",
RFC 6991, DOI 10.17487/RFC6991, July 2013, RFC 6991, DOI 10.17487/RFC6991, July 2013,
<https://www.rfc-editor.org/info/rfc6991>. <https://www.rfc-editor.org/info/rfc6991>.
skipping to change at page 49, line 38 skipping to change at line 2198
[RFC8343] Bjorklund, M., "A YANG Data Model for Interface [RFC8343] Bjorklund, M., "A YANG Data Model for Interface
Management", RFC 8343, DOI 10.17487/RFC8343, March 2018, Management", RFC 8343, DOI 10.17487/RFC8343, March 2018,
<https://www.rfc-editor.org/info/rfc8343>. <https://www.rfc-editor.org/info/rfc8343>.
[RFC8344] Bjorklund, M., "A YANG Data Model for IP Management", [RFC8344] Bjorklund, M., "A YANG Data Model for IP Management",
RFC 8344, DOI 10.17487/RFC8344, March 2018, RFC 8344, DOI 10.17487/RFC8344, March 2018,
<https://www.rfc-editor.org/info/rfc8344>. <https://www.rfc-editor.org/info/rfc8344>.
Acknowledgments Acknowledgments
This document has been largely inspired by the extensive works done This document has been largely inspired by the extensive work done by
by Andy Bierman and Peter van der Stok on [I-D.ietf-core-comi]. Andy Bierman and Peter van der Stok on [CORE-COMI]. [RFC7951] has
[RFC7951] has also been a critical input to this work. The authors also been a critical input to this work. The authors would like to
would like to thank the authors and contributors to these two drafts. thank the authors and contributors of these two documents.
The authors would also like to acknowledge the review, feedback, and The authors would also like to acknowledge the review, feedback, and
comments from Ladislav Lhotka and Jürgen Schönwälder, and from the comments from Ladislav Lhotka and Jürgen Schönwälder and from the
document shepherd Marco Tiloca. Extensive comments helped us further Document Shepherd Marco Tiloca. Extensive comments helped us further
improve the document in the IESG review process; the authors would improve the document in the IESG review process; the authors would
like to call out specifically the feedback and guidance by the like to call out specifically the feedback and guidance by the
responsible AD Francesca Palombini and the significant improvements responsible AD Francesca Palombini and the significant improvements
suggested by IESG members Benjamin Kaduk and Rob Wilton. suggested by IESG members Benjamin Kaduk and Rob Wilton.
Authors' Addresses Authors' Addresses
Michel Veillette (editor) Michel Veillette (editor)
Trilliant Networks Inc. Trilliant Networks Inc.
610 Rue du Luxembourg 610 Rue du Luxembourg
Granby Quebec J2J 2V2 Granby Quebec J2J 2V2
Canada Canada
Email: michel.veillette@trilliantinc.com Email: michel.veillette@trilliantinc.com
Ivaylo Petrov (editor) Ivaylo Petrov (editor)
Google Switzerland GmbH Google Switzerland GmbH
Brandschenkestrasse 110 Brandschenkestrasse 110
CH-8002 Zurich CH-8002 Zurich
Switzerland Switzerland
Email: ivaylopetrov@google.com Email: ivaylopetrov@google.com
Alexander Pelov Alexander Pelov
Acklio Acklio
1137A avenue des Champs Blancs 1137A avenue des Champs Blancs
35510 Cesson-Sevigne 35510 Cesson-Sevigne Cedex
France France
Email: a@ackl.io Email: a@ackl.io
Carsten Bormann Carsten Bormann
Universität Bremen TZI Universität Bremen TZI
Postfach 330440 Postfach 330440
D-28359 Bremen D-28359 Bremen
Germany Germany
Phone: +49-421-218-63921 Phone: +49-421-218-63921
Email: cabo@tzi.org Email: cabo@tzi.org
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