Internet DRAFT - draft-ietf-netmod-yang-json
draft-ietf-netmod-yang-json
NETMOD Working Group L. Lhotka
Internet-Draft CZ.NIC
Intended status: Standards Track March 26, 2016
Expires: September 27, 2016
JSON Encoding of Data Modeled with YANG
draft-ietf-netmod-yang-json-10
Abstract
This document defines encoding rules for representing configuration
data, state data, parameters of RPC operations or actions, and
notifications defined using YANG as JavaScript Object Notation (JSON)
text.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on September 27, 2016.
Copyright Notice
Copyright (c) 2016 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Terminology and Notation . . . . . . . . . . . . . . . . . . 3
3. Properties of the JSON Encoding . . . . . . . . . . . . . . . 4
4. Names and Namespaces . . . . . . . . . . . . . . . . . . . . 5
5. Encoding of YANG Data Node Instances . . . . . . . . . . . . 7
5.1. The "leaf" Data Node . . . . . . . . . . . . . . . . . . 7
5.2. The "container" Data Node . . . . . . . . . . . . . . . . 7
5.3. The "leaf-list" Data Node . . . . . . . . . . . . . . . . 8
5.4. The "list" Data Node . . . . . . . . . . . . . . . . . . 8
5.5. The "anydata" Data Node . . . . . . . . . . . . . . . . . 9
5.6. The "anyxml" Data Node . . . . . . . . . . . . . . . . . 10
5.7. Metadata Objects . . . . . . . . . . . . . . . . . . . . 10
6. Representing YANG Data Types in JSON Values . . . . . . . . . 10
6.1. Numeric Types . . . . . . . . . . . . . . . . . . . . . . 11
6.2. The "string" Type . . . . . . . . . . . . . . . . . . . . 11
6.3. The "boolean" Type . . . . . . . . . . . . . . . . . . . 11
6.4. The "enumeration" Type . . . . . . . . . . . . . . . . . 11
6.5. The "bits" Type . . . . . . . . . . . . . . . . . . . . . 11
6.6. The "binary" Type . . . . . . . . . . . . . . . . . . . . 12
6.7. The "leafref" Type . . . . . . . . . . . . . . . . . . . 12
6.8. The "identityref" Type . . . . . . . . . . . . . . . . . 12
6.9. The "empty" Type . . . . . . . . . . . . . . . . . . . . 13
6.10. The "union" Type . . . . . . . . . . . . . . . . . . . . 13
6.11. The "instance-identifier" Type . . . . . . . . . . . . . 14
7. I-JSON Compliance . . . . . . . . . . . . . . . . . . . . . . 14
8. Security Considerations . . . . . . . . . . . . . . . . . . . 15
9. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 15
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 15
10.1. Normative References . . . . . . . . . . . . . . . . . . 16
10.2. Informative References . . . . . . . . . . . . . . . . . 16
Appendix A. A Complete Example . . . . . . . . . . . . . . . . . 17
Appendix B. Change Log . . . . . . . . . . . . . . . . . . . . . 19
B.1. Changes Between Revisions -09 and -10 . . . . . . . . . . 19
B.2. Changes Between Revisions -08 and -09 . . . . . . . . . . 19
B.3. Changes Between Revisions -07 and -08 . . . . . . . . . . 20
B.4. Changes Between Revisions -06 and -07 . . . . . . . . . . 20
B.5. Changes Between Revisions -05 and -06 . . . . . . . . . . 20
B.6. Changes Between Revisions -04 and -05 . . . . . . . . . . 20
B.7. Changes Between Revisions -03 and -04 . . . . . . . . . . 20
B.8. Changes Between Revisions -02 and -03 . . . . . . . . . . 20
B.9. Changes Between Revisions -01 and -02 . . . . . . . . . . 20
B.10. Changes Between Revisions -00 and -01 . . . . . . . . . . 21
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 21
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1. Introduction
The NETCONF protocol [RFC6241] uses XML [W3C.REC-xml-20081126] for
encoding data in its Content Layer. Other management protocols might
want to use other encodings while still benefiting from using YANG
[I-D.ietf-netmod-rfc6020bis] as the data modeling language.
For example, the RESTCONF protocol [I-D.ietf-netconf-restconf]
supports two encodings: XML (media type "application/yang.data+xml")
and JSON (media type "application/yang.data+json").
The specification of YANG 1.1 data modelling language
[I-D.ietf-netmod-rfc6020bis] defines only XML encoding of data trees,
i.e., configuration data, state data, input/output parameters of RPC
operations or actions, and notifications. The aim of this document
is to define rules for encoding the same data as JavaScript Object
Notation (JSON) text [RFC7159].
2. Terminology and Notation
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119].
The following terms are defined in [I-D.ietf-netmod-rfc6020bis]:
o action,
o anydata,
o anyxml,
o augment,
o container,
o data node,
o data tree,
o identity,
o instance identifier,
o leaf,
o leaf-list,
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o list,
o module,
o RPC operation,
o submodule.
The following terms are defined in [RFC6241]:
o configuration data,
o notification,
o state data.
3. Properties of the JSON Encoding
This document defines JSON encoding for YANG data trees and their
subtrees. It is always assumed that the top-level structure in JSON-
encoded data is an object.
Instances of YANG data nodes (leafs, containers, leaf-lists, lists,
anydata and anyxml nodes) are encoded as members of a JSON object,
i.e., name/value pairs. Section 4 defines how the name part is
formed, and the following sections deal with the value part. The
encoding rules are identical for all types of data trees, i.e.,
configuration data, state data, parameters of RPC operations,
actions, and notifications.
With the exception of "anydata" encoding (Section 5.5), all rules in
this document are also applicable to YANG 1.0 [RFC6020].
Unlike XML element content, JSON values carry partial type
information (number, string, boolean). The JSON encoding is defined
so that this information is never in conflict with the data type of
the corresponding YANG leaf or leaf-list.
With the exception of anyxml and schema-less anydata nodes, it is
possible to map a JSON-encoded data tree to XML encoding as defined
in [I-D.ietf-netmod-rfc6020bis], and vice versa. However, such
conversions require the YANG data model to be available.
In order to achieve maximum interoperability while allowing
implementations to use a variety of existing JSON parsers, the JSON
encoding rules follow, as much as possible, the constraints of the
I-JSON restricted profile [RFC7493]. Section 7 discusses I-JSON
conformance in more detail.
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4. Names and Namespaces
A JSON object member name MUST be in one of the following forms:
o simple - identical to the identifier of the corresponding YANG
data node;
o namespace-qualified - the data node identifier is prefixed with
the name of the module in which the data node is defined,
separated from the data node identifier by the colon character
(":").
The name of a module determines the namespace of all data node names
defined in that module. If a data node is defined in a submodule,
then the namespace-qualified member name uses the name of the main
module to which the submodule belongs.
ABNF syntax [RFC5234] of a member name is shown in Figure 1, where
the production for "identifier" is defined in sec. 13 of
[I-D.ietf-netmod-rfc6020bis].
member-name = [identifier ":"] identifier
Figure 1: ABNF production for a JSON member name.
A namespace-qualified member name MUST be used for all members of a
top-level JSON object, and then also whenever the namespaces of the
data node and its parent node are different. In all other cases, the
simple form of the member name MUST be used.
For example, consider the following YANG module:
module example-foomod {
namespace "http://example.com/foomod";
prefix "foomod";
container top {
leaf foo {
type uint8;
}
}
}
If the data model consists only of this module, then the following is
a valid JSON-encoded configuration data:
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{
"example-foomod:top": {
"foo": 54
}
}
Note that the member of the top-level object uses the namespace-
qualified name but the "foo" leaf doesn't because it is defined in
the same module as its parent container "top".
Now, assume the container "top" is augmented from another module,
"example-barmod":
module example-barmod {
namespace "http://example.com/barmod";
prefix "barmod";
import example-foomod {
prefix "foomod";
}
augment "/foo:top" {
leaf bar {
type boolean;
}
}
}
A valid JSON-encoded configuration data containing both leafs may
then look like this:
{
"example-foomod:top": {
"foo": 54,
"example-barmod:bar": true
}
}
The name of the "bar" leaf is prefixed with the namespace identifier
because its parent is defined in a different module.
Explicit namespace identifiers are sometimes needed when encoding
values of the "identityref" and "instances-identifier" types. The
same form of namespace-qualified name as defined above is then used.
See Sections 6.8 and 6.11 for details.
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5. Encoding of YANG Data Node Instances
Every data node instance is encoded as a name/value pair where the
name is formed from the data node identifier using the rules of
Section 4. The value depends on the category of the data node as
explained in the following subsections.
Character encoding MUST be UTF-8.
5.1. The "leaf" Data Node
A leaf instance is encoded as a name/value pair where the value can
be a string, number, literal "true" or "false", or the special array
"[null]", depending on the type of the leaf (see Section 6 for the
type encoding rules).
Example: For the leaf node definition
leaf foo {
type uint8;
}
the following is a valid JSON-encoded instance:
"foo": 123
5.2. The "container" Data Node
A container instance is encoded as a name/object pair. The
container's child data nodes are encoded as members of the object.
Example: For the container definition
container bar {
leaf foo {
type uint8;
}
}
the following is a valid JSON-encoded instance:
"bar": {
"foo": 123
}
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5.3. The "leaf-list" Data Node
A leaf-list is encoded as a name/array pair, and the array elements
are values of some scalar type, which can be a string, number,
literal "true" or "false", or the special array "[null]", depending
on the type of the leaf-list (see Section 6 for the type encoding
rules).
The ordering of array elements follows the same rules as the ordering
of XML elements representing leaf-list entries in the XML encoding.
Specifically, the "ordered-by" properties (sec. 7.7.7 in
[I-D.ietf-netmod-rfc6020bis]) MUST be observed.
Example: For the leaf-list definition
leaf-list foo {
type uint8;
}
the following is a valid JSON-encoded instance:
"foo": [123, 0]
5.4. The "list" Data Node
A list instance is encoded as a name/array pair, and the array
elements are JSON objects.
The ordering of array elements follows the same rules as the ordering
of XML elements representing list entries in the XML encoding.
Specifically, the "ordered-by" properties (sec. 7.7.7 in
[I-D.ietf-netmod-rfc6020bis]) MUST be observed.
Unlike the XML encoding, where list keys are required to precede any
other siblings within a list entry, and appear in the order specified
by the data model, the order of members in a JSON-encoded list entry
is arbitrary because JSON objects are fundamentally unordered
collections of members.
Example: For the list definition
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list bar {
key foo;
leaf foo {
type uint8;
}
leaf baz {
type string;
}
}
the following is a valid JSON-encoded instance:
"bar": [
{
"foo": 123,
"baz": "zig"
},
{
"baz": "zag",
"foo": 0
}
]
5.5. The "anydata" Data Node
Anydata data node serves as a container for an arbitrary set of nodes
that otherwise appear as normal YANG-modeled data. A data model for
anydata content may or may not be known at run time. In the latter
case, converting JSON-encoded instances to the XML encoding defined
in [I-D.ietf-netmod-rfc6020bis] may be impossible.
An anydata instance is encoded in the same way as a container, i.e.,
as a value/object pair. The requirement that anydata content can be
modeled by YANG implies the following rules for the JSON text inside
the object:
o It is valid I-JSON [RFC7493].
o All object member names satisfy the ABNF production in Figure 1.
o Any JSON array contains either only unique scalar values (as a
leaf-list, see Section 5.3), or only objects (as a list, see
Section 5.4).
o The "null" value is only allowed in the single-element array
"[null]" corresponding to the encoding of the "empty" type, see
Section 6.9.
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Example: for the anydata definition
anydata data;
the following is a valid JSON-encoded instance:
"data": {
"ietf-notification:notification": {
"eventTime": "2014-07-29T13:43:01Z",
"example-event:event": {
"event-class": "fault",
"reporting-entity": {
"card": "Ethernet0"
},
"severity": "major"
}
}
}
5.6. The "anyxml" Data Node
An anyxml instance is encoded as a JSON name/value pair. The value
MUST satisfy I-JSON constraints.
Example: For the anyxml definition
anyxml bar;
the following is a valid JSON-encoded instance:
"bar": [true, null, true]
5.7. Metadata Objects
Apart from instances of YANG data nodes, a JSON document MAY contain
special object members whose name starts with the "@" character
(COMMERCIAL AT). Such members are used for special purposes such as
encoding metadata [I-D.ietf-netmod-yang-metadata]. Exact syntax and
semantics of such members are outside the scope of this document.
6. Representing YANG Data Types in JSON Values
The type of the JSON value in an instance of the leaf or leaf-list
data node depends on the type of that data node as specified in the
following subsections.
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6.1. Numeric Types
A value of the types "int8", "int16", "int32", "uint8", "uint16" and
"uint32" is represented as a JSON number.
A value of the "int64", "uint64" or "decimal64" type is represented
as a JSON string whose content is the lexical representation of the
corresponding YANG type as specified in sections 9.2.1 and 9.3.1 of
[I-D.ietf-netmod-rfc6020bis].
For example, if the type of the leaf "foo" in Section 5.1 was
"uint64" instead of "uint8", the instance would have to be encoded as
"foo": "123"
The special handling of 64-bit numbers follows from the I-JSON
recommendation to encode numbers exceeding the IEEE 754-2008 double
precision range as strings, see sec. 2.2 in [RFC7493].
6.2. The "string" Type
A "string" value is represented as a JSON string, subject to JSON
string encoding rules.
6.3. The "boolean" Type
A "boolean" value is represented as the corresponding JSON literal
name "true" or "false".
6.4. The "enumeration" Type
An "enumeration" value is represented as a JSON string - one of the
names assigned by "enum" statements in YANG.
The representation is identical to the lexical representation of the
"enumeration" type in XML, see sec. 9.6 in
[I-D.ietf-netmod-rfc6020bis].
6.5. The "bits" Type
A "bits" value is represented as a JSON string - a space-separated
sequence of names of bits that are set. The permitted bit names are
assigned by "bit" statements in YANG.
The representation is identical to the lexical representation of the
"bits" type, see sec. 9.7 in [I-D.ietf-netmod-rfc6020bis].
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6.6. The "binary" Type
A "binary" value is represented as a JSON string - base64-encoding of
arbitrary binary data.
The representation is identical to the lexical representation of the
"binary" type in XML, see sec. 9.8 in [I-D.ietf-netmod-rfc6020bis].
6.7. The "leafref" Type
A "leafref" value is represented using the same rules as the type of
the leaf to which the leafref value refers.
6.8. The "identityref" Type
An "identityref" value is represented as a string - the name of an
identity. If the identity is defined in another module than the leaf
node containing the identityref value, the namespace-qualified form
(Section 4) MUST be used. Otherwise, both the simple and namespace-
qualified forms are permitted.
For example, consider the following schematic module:
module example-mod {
...
import ietf-interfaces {
prefix if;
}
import iana-if-type {
prefix ianaift;
}
...
leaf type {
type identityref {
base "if:interface-type";
}
}
}
A valid instance of the "type" leaf is then encoded as follows:
"type": "iana-if-type:ethernetCsmacd"
The namespace identifier "iana-if-type" must be present in this case
because the "ethernetCsmacd" identity is not defined in the same
module as the "type" leaf.
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6.9. The "empty" Type
An "empty" value is represented as "[null]", i.e., an array with the
"null" literal being its only element. For the purposes of this
document, "[null]" is considered an atomic scalar value.
This encoding of the "empty" type was chosen instead of using simply
"null" in order to facilitate the use of empty leafs in common
programming languages where the "null" value of a member is treated
as if the member is not present.
Example: For the leaf definition
leaf foo {
type empty;
}
a valid instance is
"foo": [null]
6.10. The "union" Type
A value of the "union" type is encoded as the value of any of the
member types.
When validating a value of the "union" type, the type information
conveyed by the JSON encoding MUST also be taken into account. JSON
syntax thus provides additional means for resolving union member type
that are not available in XML encoding.
For example, consider the following YANG definition:
leaf bar {
type union {
type uint16;
type string;
}
}
In RESTCONF [I-D.ietf-netconf-restconf], it is possible to set the
value of "bar" in the following way when using the "application/
yang.data+xml" media type:
<bar>13.5</bar>
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because the value may be interpreted as a string, i.e., the second
member type of the union. When using the "application/
yang.data+json" media type, however, this is an error:
"bar": 13.5
In this case, the JSON encoding indicates the value is supposed to be
a number rather than a string, and it is not a valid "uint16" value.
Conversely, the value of
"bar": "1"
is to be interpreted as a string.
6.11. The "instance-identifier" Type
An "instance-identifier" value is encoded as a string that is
analogical to the lexical representation in XML encoding, see
sec. 9.13.3 in [I-D.ietf-netmod-rfc6020bis]. However, the encoding
of namespaces in instance-identifier values follows the rules stated
in Section 4, namely:
o The leftmost (top-level) data node name is always in the
namespace-qualified form.
o Any subsequent data node name is in the namespace-qualified form
if the node is defined in another module than its parent node, and
the simple form is used otherwise. This rule also holds for node
names appearing in predicates.
For example,
/ietf-interfaces:interfaces/interface[name='eth0']/ietf-ip:ipv4/ip
is a valid instance-identifer value because the data nodes
"interfaces", "interface" and "name" are defined in the module "ietf-
interfaces", whereas "ipv4" and "ip" are defined in "ietf-ip".
7. I-JSON Compliance
I-JSON [RFC7493] is a restricted profile of JSON that guarantees
maximum interoperability for protocols that use JSON in their
messages, no matter what JSON encoders/decoders are used in protocol
implementations. The encoding defined in this document therefore
observes the I-JSON requirements and recommendations as closely as
possible.
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In particular, the following properties are guaranteed:
o Character encoding is UTF-8.
o Member names within the same JSON object are always unique.
o The order of JSON object members is never relied upon.
o Numbers of any type supported by YANG can be exchanged reliably.
See Section 6.1 for details.
The JSON encoding defined in this document deviates from I-JSON only
in the representation of the "binary" type. In order to remain
compatible with XML encoding, the base64 encoding scheme is used
(Section 6.6), whilst I-JSON recommends base64url instead.
8. Security Considerations
This document defines an alternative encoding for data modeled in the
YANG data modeling language. As such, it doesn't contribute any new
security issues beyond those discussed in sec. 16 of
[I-D.ietf-netmod-rfc6020bis].
This document defines no mechanisms for signing and encrypting data
modeled with YANG. Under normal circumstances, data security and
integrity is guaranteed by the management protocol in use, such as
NETCONF [RFC6241] or RESTCONF [I-D.ietf-netconf-restconf]. If it is
not the case, external mechanisms, such as PKCS #7 [RFC2315] or JOSE
([RFC7515] and [RFC7516]), need to be considered.
JSON processing is rather different from XML, and JSON parsers may
thus suffer from other types of vulnerabilities than their XML
counterparts. To minimize these new security risks, software on the
receiving side SHOULD reject all messages that do not comply to the
rules of this document and reply with an appropriate error message to
the sender.
9. Acknowledgments
The author wishes to thank Andy Bierman, Martin Bjorklund, Dean
Bogdanovic, Balazs Lengyel, Juergen Schoenwaelder and Phil Shafer for
their helpful comments and suggestions.
10. References
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10.1. Normative References
[I-D.ietf-netmod-rfc6020bis]
Bjorklund, M., "The YANG 1.1 Data Modeling Language",
draft-ietf-netmod-rfc6020bis-11 (work in progress),
February 2016.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<http://www.rfc-editor.org/info/rfc2119>.
[RFC5234] Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax
Specifications: ABNF", STD 68, RFC 5234,
DOI 10.17487/RFC5234, January 2008,
<http://www.rfc-editor.org/info/rfc5234>.
[RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
and A. Bierman, Ed., "Network Configuration Protocol
(NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011,
<http://www.rfc-editor.org/info/rfc6241>.
[RFC7159] Bray, T., Ed., "The JavaScript Object Notation (JSON) Data
Interchange Format", RFC 7159, DOI 10.17487/RFC7159, March
2014, <http://www.rfc-editor.org/info/rfc7159>.
[RFC7493] Bray, T., Ed., "The I-JSON Message Format", RFC 7493,
DOI 10.17487/RFC7493, March 2015,
<http://www.rfc-editor.org/info/rfc7493>.
10.2. Informative References
[I-D.ietf-netconf-restconf]
Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
Protocol", draft-ietf-netconf-restconf-10 (work in
progress), March 2016.
[I-D.ietf-netmod-yang-metadata]
Lhotka, L., "Defining and Using Metadata with YANG",
draft-ietf-netmod-yang-metadata-07 (work in progress),
March 2016.
[RFC2315] Kaliski, B., "PKCS #7: Cryptographic Message Syntax
Version 1.5", RFC 2315, DOI 10.17487/RFC2315, March 1998,
<http://www.rfc-editor.org/info/rfc2315>.
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[RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for
the Network Configuration Protocol (NETCONF)", RFC 6020,
DOI 10.17487/RFC6020, October 2010,
<http://www.rfc-editor.org/info/rfc6020>.
[RFC7223] Bjorklund, M., "A YANG Data Model for Interface
Management", RFC 7223, DOI 10.17487/RFC7223, May 2014,
<http://www.rfc-editor.org/info/rfc7223>.
[RFC7515] Jones, M., Bradley, J., and N. Sakimura, "JSON Web
Signature (JWS)", RFC 7515, DOI 10.17487/RFC7515, May
2015, <http://www.rfc-editor.org/info/rfc7515>.
[RFC7516] Jones, M. and J. Hildebrand, "JSON Web Encryption (JWE)",
RFC 7516, DOI 10.17487/RFC7516, May 2015,
<http://www.rfc-editor.org/info/rfc7516>.
[W3C.REC-xml-20081126]
Bray, T., Paoli, J., Sperberg-McQueen, M., Maler, E., and
F. Yergeau, "Extensible Markup Language (XML) 1.0 (Fifth
Edition)", World Wide Web Consortium Recommendation REC-
xml-20081126, November 2008,
<http://www.w3.org/TR/2008/REC-xml-20081126>.
Appendix A. A Complete Example
The JSON document shown below represents the same data as the reply
to the NETCONF <get> request appearing in Appendix D of [RFC7223].
The data model is a combination of two YANG modules: "ietf-
interfaces" and "ex-vlan" (the latter is an example module from
Appendix C of [RFC7223]). The "if-mib" feature defined in the "ietf-
interfaces" module is supported.
{
"ietf-interfaces:interfaces": {
"interface": [
{
"name": "eth0",
"type": "iana-if-type:ethernetCsmacd",
"enabled": false
},
{
"name": "eth1",
"type": "iana-if-type:ethernetCsmacd",
"enabled": true,
"ex-vlan:vlan-tagging": true
},
{
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"name": "eth1.10",
"type": "iana-if-type:l2vlan",
"enabled": true,
"ex-vlan:base-interface": "eth1",
"ex-vlan:vlan-id": 10
},
{
"name": "lo1",
"type": "iana-if-type:softwareLoopback",
"enabled": true
}
]
},
"ietf-interfaces:interfaces-state": {
"interface": [
{
"name": "eth0",
"type": "iana-if-type:ethernetCsmacd",
"admin-status": "down",
"oper-status": "down",
"if-index": 2,
"phys-address": "00:01:02:03:04:05",
"statistics": {
"discontinuity-time": "2013-04-01T03:00:00+00:00"
}
},
{
"name": "eth1",
"type": "iana-if-type:ethernetCsmacd",
"admin-status": "up",
"oper-status": "up",
"if-index": 7,
"phys-address": "00:01:02:03:04:06",
"higher-layer-if": [
"eth1.10"
],
"statistics": {
"discontinuity-time": "2013-04-01T03:00:00+00:00"
}
},
{
"name": "eth1.10",
"type": "iana-if-type:l2vlan",
"admin-status": "up",
"oper-status": "up",
"if-index": 9,
"lower-layer-if": [
"eth1"
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],
"statistics": {
"discontinuity-time": "2013-04-01T03:00:00+00:00"
}
},
{
"name": "eth2",
"type": "iana-if-type:ethernetCsmacd",
"admin-status": "down",
"oper-status": "down",
"if-index": 8,
"phys-address": "00:01:02:03:04:07",
"statistics": {
"discontinuity-time": "2013-04-01T03:00:00+00:00"
}
},
{
"name": "lo1",
"type": "iana-if-type:softwareLoopback",
"admin-status": "up",
"oper-status": "up",
"if-index": 1,
"statistics": {
"discontinuity-time": "2013-04-01T03:00:00+00:00"
}
}
]
}
}
Appendix B. Change Log
RFC Editor: Remove this section upon publication as an RFC.
B.1. Changes Between Revisions -09 and -10
o A sentence about signing and encrypting data was added, together
with informative references to RFCs 2315, 7515 and 7516.
B.2. Changes Between Revisions -08 and -09
o References to RFC 6241 term in the Terminology section were added.
o Prefixes in the example in Sec. 4 were changed so as to be
different from node names.
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B.3. Changes Between Revisions -07 and -08
o Changed the names of example modules so that they start with
"example-".
B.4. Changes Between Revisions -06 and -07
o General permit on object members whose names start with "@".
B.5. Changes Between Revisions -05 and -06
o More text and a new example about resolving union-type values.
B.6. Changes Between Revisions -04 and -05
o Removed section "Validation of JSON-encoded Instance Data" and
other text about XML-JSON mapping.
o Added section "Properties of the JSON Encoding".
B.7. Changes Between Revisions -03 and -04
o I-D.ietf-netmod-rfc6020bis is used as a normative reference
instead of RFC 6020.
o Removed noncharacters as an I-JSON issue because it doesn't exist
in YANG 1.1.
o Section about anydata encoding was added.
o Require I-JSON for anyxml encoding.
o Use ABNF for defining qualified name.
B.8. Changes Between Revisions -02 and -03
o Namespace encoding is defined without using RFC 2119 keywords.
o Specification for anyxml nodes was extended and clarified.
o Text about ordering of list entries was corrected.
B.9. Changes Between Revisions -01 and -02
o Encoding of namespaces in instance-identifiers was changed.
o Text specifying the order of array elements in leaf-list and list
instances was added.
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B.10. Changes Between Revisions -00 and -01
o Metadata encoding was moved to a separate I-D, draft-lhotka-
netmod-yang-metadata.
o JSON encoding is now defined directly rather than via XML-JSON
mapping.
o The rules for namespace encoding has changed. This affect both
node instance names and instance-identifiers.
o I-JSON-related changes. The most significant is the string
encoding of 64-bit numbers.
o When validating union type, the partial type info present in JSON
encoding is taken into account.
o Added section about I-JSON compliance.
o Updated the example in appendix.
o Wrote Security Considerations.
o Removed IANA Considerations as there are none.
Author's Address
Ladislav Lhotka
CZ.NIC
Email: lhotka@nic.cz
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