draft-ietf-core-multipart-ct-04.txt   rfc8710.txt 
CoRE T. Fossati Internet Engineering Task Force (IETF) T. Fossati
Internet-Draft ARM Request for Comments: 8710 ARM
Intended status: Standards Track K. Hartke Category: Standards Track K. Hartke
Expires: February 22, 2020 Ericsson ISSN: 2070-1721 Ericsson
C. Bormann C. Bormann
Universitaet Bremen TZI Universität Bremen TZI
August 21, 2019 February 2020
Multipart Content-Format for CoAP Multipart Content-Format for the Constrained Application Protocol (CoAP)
draft-ietf-core-multipart-ct-04
Abstract Abstract
This memo defines application/multipart-core, an application- This memo defines application/multipart-core, an application-
independent media-type that can be used to combine representations of independent media type that can be used to combine representations of
zero or more different media types into a single message, such as a zero or more different media types (each with a Constrained
CoAP request or response body, with minimal framing overhead, each Application Protocol (CoAP) Content-Format identifier) into a single
along with a CoAP Content-Format identifier. representation, with minimal framing overhead.
Status of This Memo Status of This Memo
This Internet-Draft is submitted in full conformance with the This is an Internet Standards Track document.
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months 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 February 22, 2020. 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/rfc8710.
Copyright Notice Copyright Notice
Copyright (c) 2019 IETF Trust and the persons identified as the Copyright (c) 2020 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info) in effect on the date of (https://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction
1.1. Requirements Language . . . . . . . . . . . . . . . . . . 3 1.1. Requirements Language
2. Multipart Content-Format Encoding . . . . . . . . . . . . . . 4 2. Multipart Content-Format Encoding
3. Usage Example: Observing Resources . . . . . . . . . . . . . 4 3. Usage Example: Observing Resources
4. Implementation Hints . . . . . . . . . . . . . . . . . . . . 5 4. Implementation Hints
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 6 5. IANA Considerations
5.1. Registration of media type application/multipart-core . . 6 5.1. Registration of Media Type application/multipart-core
5.2. Registration of a Content-Format identifier for 5.2. Registration of a Content-Format Identifier for
application/multipart-core . . . . . . . . . . . . . . . 7 application/multipart-core
6. Security Considerations . . . . . . . . . . . . . . . . . . . 8 6. Security Considerations
7. References . . . . . . . . . . . . . . . . . . . . . . . . . 8 7. References
7.1. Normative References . . . . . . . . . . . . . . . . . . 8 7.1. Normative References
7.2. Informative References . . . . . . . . . . . . . . . . . 8 7.2. Informative References
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 9 Acknowledgements
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 9 Authors' Addresses
1. Introduction 1. Introduction
This memo defines application/multipart-core, an application- This memo defines application/multipart-core, an application-
independent media-type that can be used to combine representations of independent media type that can be used to combine representations of
zero or more different media types, each along with a CoAP Content- zero or more different media types (each with a CoAP Content-Format
Format identifier, into a single representation, with minimal framing identifier [RFC7252]) into a single representation, with minimal
overhead. This combined representation may then be carried in a framing overhead.
single message, such as a CoAP [RFC7252] request or response body.
This simple and efficient binary framing mechanism can be employed to This simple and efficient binary framing mechanism can be employed to
create application specific request and response bodies which build create application-specific message bodies that build on multiple
on multiple already existing media types. already existing media types.
As the name of the media-type suggests, it is inspired by the As the name of the media type suggests, application/multipart-core
multipart media types that started to be defined with the original was inspired by the multipart media types initially defined in the
set of MIME specifications [RFC2046]. However, while those needed to original set of MIME specifications [RFC2046] and later. However,
focus on the syntactic aspects of integrating multiple while those needed to focus on the syntactic aspects of integrating
representations into one e-mail, transfer protocols providing full multiple representations into one email, transfer protocols providing
data transparency such as CoAP as well as readily available encoding full data transparency such as CoAP as well as readily available
formats such as the Concise Binary Object Representation (CBOR) encoding formats such as the Concise Binary Object Representation
[RFC7049] shift the focus towards the intended use of the combined (CBOR) [RFC7049] shift the focus towards the intended use of the
representations. In this respect, the basic intent of the combined representations. In this respect, the basic intent of the
application/multipart-core media type is like that of multipart/mixed application/multipart-core media type is like that of multipart/mixed
(Section 5.1.3 of [RFC2046]). The detailed semantics of the (Section 5.1.3 of [RFC2046]); however, the semantics are relaxed to
representations are refined by the context established by the allow for both ordered and unordered collections of media types.
application in the accompanying request parameters, e.g., the
resource URI and any further options (header fields), but three usage
scenarios are envisioned:
The individual representations in an application/multipart-core body Historical Note: Experience with multipart/mixed in email has
occur in a sequence, which may be employed by an application where shown that recipients that care about order of included body parts
such a sequence is natural, e.g. for a number of audio snippets in will process them in the order they are listed inside multipart/
various formats to be played out in that sequence, or search results mixed, and recipients that don't care about the order will ignore
returned in order of relevance. it anyway. The media type multipart/parallel that was intended
for unordered collections didn't deploy.
In other cases, an application may be more interested in a bag of The detailed semantics of the representations are refined by the
representations, which are distinguished by their Content-Format context established by the application in the accompanying request
identifier, such as an audio snippet and a text representation parameters, e.g., the resource URI and any further options (header
fields), but three usage scenarios are envisioned:
In one case, the individual representations in an application/
multipart-core message body occur in a sequence, which may be
employed by an application where such a sequence is natural, e.g.,
for a number of audio snippets in various formats to be played out in
that sequence or search results returned in order of relevance.
In another case, an application may be more interested in a bag of
representations (which are distinguished by their Content-Format
identifiers), such as an audio snippet and a text representation
accompanying it. In such a case, the sequence in which these occur accompanying it. In such a case, the sequence in which these occur
may not be relevant to the application. This specification adds the may not be relevant to the application. This specification adds the
option of substituting a null value for the representation of an option of substituting a null value for the representation of an
optional part, which indicates that the part is not present. optional part, which indicates that the part is not present.
A third situation that is common only ever has a single A third common situation only has a single representation in the
representation in the sequence, where the sender already selects just sequence, and the sender selects just one of a set of formats
one of a set of formats possible for this situation. This kind of possible for this situation. This kind of union "type" of formats
union "type" of formats may also make the presence of the actual may also make the presence of the actual representation optional, the
representation optional, the omission of which leads to a zero-length omission of which leads to a zero-length array.
array.
Where these rules are not sufficient for an application, it might Where these rules are not sufficient, an application might still use
still use the general format defined here, but register a new media the general format defined here but register a new media type and an
type and an associated Content-Format identifier to associate the associated Content-Format identifier to associate the representation
representation with these more specific semantics instead of using with these more specific semantics instead of using the application/
the application/multipart-core media type. multipart-core media type.
Also, future specifications might want to define rough equivalents Also, future specifications might want to define rough equivalents
for other multipart media types with specific semantics not covered for other multipart media types with specific semantics not covered
by the present specification, such as multipart/alternative by the present specification, such as multipart/alternative
(Section 5.1.4 of [RFC2046]), where several alternative (Section 5.1.4 of [RFC2046]), where several alternative
representations are provided in the message, but only one of those is representations are provided in the message body, but only one of
to be selected by the recipient for its use (this is less likely to those is to be selected by the recipient for its use (this is less
be useful in a constrained environment that has facilities for pre- likely to be useful in a constrained environment that has facilities
flight discovery). for pre-flight discovery).
1.1. Requirements Language 1.1. Requirements Language
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.
2. Multipart Content-Format Encoding 2. Multipart Content-Format Encoding
A representation of media-type application/multipart-core contains a A representation of media type application/multipart-core contains a
collection of zero or more representations, each along with their collection of zero or more representations, each along with their
respective content format. respective Content-Format.
The collection is encoded as a CBOR [RFC7049] array with an even The collection is encoded as a CBOR [RFC7049] array with an even
number of elements. Counting from zero, the odd-numbered elements number of elements. Counting from zero, the odd-numbered elements
are a byte string containing a representation, or the value "null" if are a byte string containing a representation or the value "null" (if
an optional part is indicated as not given. The (even-numbered) an optional part is indicated as not given). The (even-numbered)
element preceding each of these is an unsigned integer specifying the element preceding each of these is an unsigned integer specifying the
content format ID of the representation following it. Content-Format ID of the representation following it.
For example, a collection containing two representations, one with For example, a collection containing two representations, one with
content format ID 42 and one with content format ID 0, looks like Content-Format ID 42 and one with Content-Format ID 0, looks like
this in CBOR diagnostic notation: this in CBOR diagnostic notation:
[42, h'0123456789abcdef', 0, h'3031323334'] [42, h'0123456789abcdef', 0, h'3031323334']
For illustration, the structure of an application/multipart-core For illustration, the structure of an application/multipart-core
representation can be described by the CDDL [RFC8610] specification representation can be described by the Concise Data Definition
in Figure 1: Language (CDDL) [RFC8610] specification in Figure 1:
multipart-core = [* multipart-part] multipart-core = [* multipart-part]
multipart-part = (type: uint .size 2, part: bytes / null) multipart-part = (type: uint .size 2, part: bytes / null)
Figure 1: CDDL for application/multipart-core Figure 1: CDDL for application/multipart-core
This format is intended as a strict specification: An implementation This format is intended as a strict specification: an implementation
MUST stop processing the representation if there is a CBOR well- MUST stop processing the representation if there is a CBOR well-
formedness error, a deviation from the structure defined above, or formedness error, a deviation from the structure defined above, or
any residual data left after processing the CBOR data item. (This any residual data left after processing the CBOR data item. (This
generally means the representation is not processed at all except if generally means the representation is not processed at all unless
some streaming processing has already happened.) some streaming processing has already happened.)
3. Usage Example: Observing Resources 3. Usage Example: Observing Resources
This section illustrates one less obvious example for using This section illustrates a less obvious example for using
application/multipart-core: combining it with observing a resource application/multipart-core: combining it with observing a resource
[RFC7641] to handle pending results. [RFC7641] to handle pending results.
When a client registers to observe a resource for which no When a client registers to observe a resource for which no
representation is available yet, the server may send one or more 2.05 representation is available yet, the server may send one or more 2.05
(Content) notifications before sending the first actual 2.05 (Content) notifications that indicate the lack of an actual
(Content) or 2.03 (Valid) notification. A diagram depicting possible representation. Later on, when one becomes available, the server
resulting sequences of notifications, identified by their respective will send the first actual 2.05 (Content) or 2.03 (Valid)
response code, is shown in Figure 2. notification. A diagram depicting possible resulting sequences of
notifications, identified by their respective response code, is shown
in Figure 2.
__________ __________ __________ __________ __________ __________
| | | | | | | | | | | |
---->| 2.05 |---->| 2.05 / |---->| 4.xx / | ---->| 2.05 |---->| 2.05 / |---->| 4.xx / |
| Pending | | 2.03 | | 5.xx | | Pending | | 2.03 | | 5.xx |
|__________| |__________| |__________| |__________| |__________| |__________|
^ \ \ ^ \ ^ ^ \ \ ^ \ ^
\__/ \ \___/ / \__/ \ \___/ /
\_______________________/ \_______________________/
Figure 2: Sequence of Notifications Figure 2: Sequence of Notifications
The specification of the Observe option requires that all The specification of the Observe option requires that all
notifications carry the same Content-Format. The application/ notifications carry the same Content-Format. The application/
multipart-core media type can be used to provide that Content-Format: multipart-core media type can be used to provide that Content-Format,
e.g., carrying an empty list of representations in the case marked as e.g., by carrying an empty list of representations in the case marked
"Pending" in Figure 2, and carrying a single representation specified as "Pending" in Figure 2 and carrying a single representation
as the target content-format in the case in the middle of the figure. specified as the target Content-Format in the case in the middle of
the figure.
4. Implementation Hints 4. Implementation Hints
This section describes the serialization for readers that may be new This section describes the serialization for readers that may be new
to CBOR. It does not contain any new information. to CBOR. It does not contain any new information.
An application/multipart-core representation carrying no An application/multipart-core representation carrying no
representations is represented by an empty CBOR array, which is representations is represented by an empty CBOR array, which is
serialized as a single byte with the value 0x80. serialized as a single byte with the value 0x80.
An application/multipart-core representation carrying a single An application/multipart-core representation carrying a single
representation is represented by a two-element CBOR array, which is representation is represented by a two-element CBOR array, which is
serialized as 0x82 followed by the two elements. The first element serialized as 0x82 followed by the two elements. The first element
is an unsigned integer for the Content-Format value, which is is an unsigned integer for the Content-Format value, which is
represented as described in Table 1. The second element is the represented as described in Table 1. The second element is the
object as a byte string, which is represented as a length as object as a byte string, which is represented as a length as
described in Table 2 followed by the bytes of the object. described in Table 2 followed by the bytes of the object.
+----------------+------------+ +----------------+------------+
| Serialization | Value | | Serialization | Value |
+----------------+------------+ +================+============+
| 0x00..0x17 | 0..23 | | 0x00..0x17 | 0..23 |
+----------------+------------+
| 0x18 0xnn | 24..255 | | 0x18 0xnn | 24..255 |
+----------------+------------+
| 0x19 0xnn 0xnn | 256..65535 | | 0x19 0xnn 0xnn | 256..65535 |
+----------------+------------+ +----------------+------------+
Table 1: Serialization of content-format Table 1: Serialization of
Content-Format
+-----------------------------+-------------------+ +-----------------------------+-------------------+
| Serialization | Length | | Serialization | Length |
+-----------------------------+-------------------+ +=============================+===================+
| 0x40..0x57 | 0..23 | | 0x40..0x57 | 0..23 |
+-----------------------------+-------------------+
| 0x58 0xnn | 24..255 | | 0x58 0xnn | 24..255 |
+-----------------------------+-------------------+
| 0x59 0xnn 0xnn | 256..65535 | | 0x59 0xnn 0xnn | 256..65535 |
+-----------------------------+-------------------+
| 0x5a 0xnn 0xnn 0xnn 0xnn | 65536..4294967295 | | 0x5a 0xnn 0xnn 0xnn 0xnn | 65536..4294967295 |
+-----------------------------+-------------------+
| 0x5b 0xnn .. 0xnn (8 bytes) | 4294967296.. | | 0x5b 0xnn .. 0xnn (8 bytes) | 4294967296.. |
+-----------------------------+-------------------+ +-----------------------------+-------------------+
Table 2: Serialization of object length Table 2: Serialization of Object Length
For example, a single text/plain object (content-format 0) of value For example, a single text/plain object (Content-Format 0) of value
"Hello World" (11 characters) would be serialized as "Hello World" (11 characters) would be serialized as follows:
0x82 0x00 0x4b H e l l o 0x20 W o r l d 0x82 0x00 0x4b H e l l o 0x20 W o r l d
In effect, the serialization for a single object is done by prefixing In effect, the serialization for a single object is done by prefixing
the object with information that there is one object (here: 0x82), the object with information that there is one object (here: 0x82),
about its content-format (here: 0x00) and its length (here: 0x4b). information about its Content-Format (here: 0x00), and information
regarding its length (here: 0x4b).
For more than one representation included in an application/ For more than one representation included in an application/
multipart-core representation, the head of the CBOR array is adjusted multipart-core representation, the head of the CBOR array is adjusted
(0x84 for two representations, 0x86 for three, ...) and the sequences (0x84 for two representations, 0x86 for three, etc.), and the
of content-format and embedded representations follow. sequences of Content-Format and embedded representations follow.
For instance, the example from Section 2 would be serialized as: For instance, the example from Section 2 would be serialized as
follows:
0x84 (*) 0x182A 0x48 0x0123456789ABCDEF (+) 0x00 0x45 0x3031323334 0x84 (*) 0x182A 0x48 0x0123456789ABCDEF (+) 0x00 0x45 0x3031323334
where (*) marks the start of the information about the first where (*) marks the start of the information about the first
representation (content-format 42, byte string length 8) and, (+), of representation (Content-Format 42, byte string length 8), and (+)
the second representation (content-format 0, byte string length 5). marks the start of the second representation (Content-Format 0, byte
string length 5).
5. IANA Considerations 5. IANA Considerations
5.1. Registration of media type application/multipart-core 5.1. Registration of Media Type application/multipart-core
IANA is requested to register the following media type [RFC6838]: IANA has registered the following media type [RFC6838]:
Type name: application Type name: application
Subtype name: multipart-core Subtype name: multipart-core
Required parameters: N/A Required parameters: N/A
Optional parameters: N/A Optional parameters: N/A
Encoding considerations: binary Encoding considerations: binary
Security considerations: See the Security Considerations Section of Security considerations: See the Security Considerations section of
RFCthis RFC 8710.
Interoperability considerations: N/A Interoperability considerations: N/A
Published specification: RFCthis Published specification: RFC 8710
Applications that use this media type: Applications that need to Applications that use this media type: Applications that need to
combine representations of zero or more different media types into combine representations of zero or more different media types into
one, e.g., EST-CoAP [I-D.ietf-ace-coap-est] one, e.g., EST over secure CoAP (EST-CoAP) [EST-COAPS]
Fragment identifier considerations: The syntax and semantics of Fragment identifier considerations: The syntax and semantics of
fragment identifiers specified for "application/multipart-core" is fragment identifiers specified for application/multipart-core are
as specified for "application/cbor". (At publication of this as specified for application/cbor. (At publication of this
document, there is no fragment identification syntax defined for document, there is no fragment identification syntax defined for
"application/cbor".) application/cbor.)
Additional information:
Deprecated alias names for this type: N/A Additional information: Deprecated alias names for this type: N/A
Magic number(s): N/A Magic number(s): N/A
File extension(s): N/A File extension(s): N/A
Macintosh file type code(s): N/A Macintosh file type code(s): N/A
Person & email address to contact for further information: Person & email address to contact for further information:
iesg&ietf.org iesg@ietf.org
Intended usage: COMMON Intended usage: COMMON
Restrictions on usage: N/A Restrictions on usage: N/A
Author: CoRE WG Author: CoRE WG
Change controller: IESG Change controller: IESG
Provisional registration? (standards tree only): no Provisional registration? (standards tree only): no
5.2. Registration of a Content-Format identifier for application/ 5.2. Registration of a Content-Format Identifier for application/
multipart-core multipart-core
IANA is requested to register the following Content-Format to the IANA has registered the following Content-Format in the "CoAP
"CoAP Content-Formats" subregistry, within the "Constrained RESTful Content-Formats" subregistry within the "Constrained RESTful
Environments (CoRE) Parameters" registry, from the Expert Review Environments (CoRE) Parameters" registry:
space (0..255):
+----------------------------+----------+------+-----------+ +----------------------------+----------+----+-----------+
| Media Type | Encoding | ID | Reference | | Media Type | Encoding | ID | Reference |
+----------------------------+----------+------+-----------+ +============================+==========+====+===========+
| application/multipart-core | -- | TBD1 | RFCthis | | application/multipart-core | - | 62 | RFC 8710 |
+----------------------------+----------+------+-----------+ +----------------------------+----------+----+-----------+
Table 3: Addition to "CoAP Content-Formats" Registry
6. Security Considerations 6. Security Considerations
The security considerations of [RFC7049] apply. In particular, The security considerations of [RFC7049] apply. In particular,
resource exhaustion attacks may employ large values for the byte resource exhaustion attacks may employ large values for the byte
string size fields, or deeply nested structures of recursively string size fields or employ deeply nested structures of recursively
embedded application/multipart-core representations. embedded application/multipart-core representations.
7. References 7. References
7.1. Normative References 7.1. Normative References
[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>.
skipping to change at page 8, line 44 skipping to change at line 387
Application Protocol (CoAP)", RFC 7252, Application Protocol (CoAP)", RFC 7252,
DOI 10.17487/RFC7252, June 2014, DOI 10.17487/RFC7252, June 2014,
<https://www.rfc-editor.org/info/rfc7252>. <https://www.rfc-editor.org/info/rfc7252>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>. May 2017, <https://www.rfc-editor.org/info/rfc8174>.
7.2. Informative References 7.2. Informative References
[I-D.ietf-ace-coap-est] [EST-COAPS]
Stok, P., Kampanakis, P., Richardson, M., and S. Raza, Stok, P., Kampanakis, P., Richardson, M., and S. Raza,
"EST over secure CoAP (EST-coaps)", draft-ietf-ace-coap- "EST over secure CoAP (EST-coaps)", Work in Progress,
est-12 (work in progress), June 2019. Internet-Draft, draft-ietf-ace-coap-est-18, 6 January
2020,
<https://tools.ietf.org/html/draft-ietf-ace-coap-est-18>.
[RFC2046] Freed, N. and N. Borenstein, "Multipurpose Internet Mail [RFC2046] Freed, N. and N. Borenstein, "Multipurpose Internet Mail
Extensions (MIME) Part Two: Media Types", RFC 2046, Extensions (MIME) Part Two: Media Types", RFC 2046,
DOI 10.17487/RFC2046, November 1996, DOI 10.17487/RFC2046, November 1996,
<https://www.rfc-editor.org/info/rfc2046>. <https://www.rfc-editor.org/info/rfc2046>.
[RFC6838] Freed, N., Klensin, J., and T. Hansen, "Media Type [RFC6838] Freed, N., Klensin, J., and T. Hansen, "Media Type
Specifications and Registration Procedures", BCP 13, Specifications and Registration Procedures", BCP 13,
RFC 6838, DOI 10.17487/RFC6838, January 2013, RFC 6838, DOI 10.17487/RFC6838, January 2013,
<https://www.rfc-editor.org/info/rfc6838>. <https://www.rfc-editor.org/info/rfc6838>.
skipping to change at page 9, line 28 skipping to change at line 417
<https://www.rfc-editor.org/info/rfc7641>. <https://www.rfc-editor.org/info/rfc7641>.
[RFC8610] Birkholz, H., Vigano, C., and C. Bormann, "Concise Data [RFC8610] Birkholz, H., Vigano, C., and C. Bormann, "Concise Data
Definition Language (CDDL): A Notational Convention to Definition Language (CDDL): A Notational Convention to
Express Concise Binary Object Representation (CBOR) and Express Concise Binary Object Representation (CBOR) and
JSON Data Structures", RFC 8610, DOI 10.17487/RFC8610, JSON Data Structures", RFC 8610, DOI 10.17487/RFC8610,
June 2019, <https://www.rfc-editor.org/info/rfc8610>. June 2019, <https://www.rfc-editor.org/info/rfc8610>.
Acknowledgements Acknowledgements
Most of the text in this draft is from earlier contributions by two Most of the text in this document is from earlier contributions by
of the authors, Thomas Fossati and Klaus Hartke. The re-mix in this two of the authors, Thomas Fossati and Klaus Hartke. This earlier
document is based on the requirements in [I-D.ietf-ace-coap-est], work was reorganized in this document based on the requirements in
based on discussions with Michael Richardson, Panos Kampanis and [EST-COAPS] and discussions with Michael Richardson, Panos Kampanis,
Peter van der Stok. and Peter van der Stok.
Authors' Addresses Authors' Addresses
Thomas Fossati Thomas Fossati
ARM ARM
Email: thomas.fossati@arm.com Email: thomas.fossati@arm.com
Klaus Hartke Klaus Hartke
Ericsson Ericsson
Torshamnsgatan 23 Torshamnsgatan 23
Stockholm SE-16483 SE-16483 Stockholm
Sweden Sweden
Email: klaus.hartke@ericsson.com Email: klaus.hartke@ericsson.com
Carsten Bormann Carsten Bormann
Universitaet Bremen TZI Universität Bremen TZI
Postfach 330440 Postfach 330440
Bremen D-28359 D-28359 Bremen
Germany Germany
Phone: +49-421-218-63921 Phone: +49-421-218-63921
Email: cabo@tzi.org Email: cabo@tzi.org
 End of changes. 71 change blocks. 
156 lines changed or deleted 175 lines changed or added

This html diff was produced by rfcdiff 1.47. The latest version is available from http://tools.ietf.org/tools/rfcdiff/