draft-ietf-core-senml-00.txt		draft-ietf-core-senml-01.txt
	Network Working Group C. Jennings		Network Working Group C. Jennings
	Internet-Draft Cisco		Internet-Draft Cisco
	Intended status: Standards Track Z. Shelby		Intended status: Standards Track Z. Shelby
	Expires: October 21, 2016 ARM		Expires: January 9, 2017 ARM
	J. Arkko		J. Arkko
	A. Keranen		A. Keranen
	Ericsson		Ericsson
	April 19, 2016		C. Bormann
			Universitaet Bremen TZI
			July 8, 2016
	Media Types for Sensor Markup Language (SenML)		Media Types for Sensor Markup Language (SenML)
	draft-ietf-core-senml-00		draft-ietf-core-senml-01
	Abstract		Abstract
	This specification defines media types for representing simple sensor		This specification defines media types for representing simple sensor
	measurements and device parameters in the Sensor Markup Language		measurements and device parameters in the Sensor Markup Language
	(SenML). Representations are defined in JavaScript Object Notation		(SenML). Representations are defined in JavaScript Object Notation
	(JSON), Concise Binary Object Representation (CBOR), eXtensible		(JSON), Concise Binary Object Representation (CBOR), eXtensible
	Markup Language (XML), and Efficient XML Interchange (EXI), which		Markup Language (XML), and Efficient XML Interchange (EXI), which
	share the common SenML data model. A simple sensor, such as a		share the common SenML data model. A simple sensor, such as a
	temperature sensor, could use this media type in protocols such as		temperature sensor, could use this media type in protocols such as
	skipping to change at page 1, line 42 ¶		skipping to change at page 1, line 44 ¶
	Internet-Drafts are working documents of the Internet Engineering		Internet-Drafts are working documents of the Internet Engineering
	Task Force (IETF). Note that other groups may also distribute		Task Force (IETF). Note that other groups may also distribute
	working documents as Internet-Drafts. The list of current Internet-		working documents as Internet-Drafts. The list of current Internet-
	Drafts is at http://datatracker.ietf.org/drafts/current/.		Drafts is at http://datatracker.ietf.org/drafts/current/.
	Internet-Drafts are draft documents valid for a maximum of six months		Internet-Drafts are draft documents valid for a maximum of six months
	and may be updated, replaced, or obsoleted by other documents at any		and may be updated, replaced, or obsoleted by other documents at any
	time. It is inappropriate to use Internet-Drafts as reference		time. It is inappropriate to use Internet-Drafts as reference
	material or to cite them other than as "work in progress."		material or to cite them other than as "work in progress."
	This Internet-Draft will expire on October 21, 2016.		This Internet-Draft will expire on January 9, 2017.
	Copyright Notice		Copyright Notice
	Copyright (c) 2016 IETF Trust and the persons identified as the		Copyright (c) 2016 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
	(http://trustee.ietf.org/license-info) in effect on the date of		(http://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. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . 3		1. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . 3
	2. Requirements and Design Goals . . . . . . . . . . . . . . . . 3		2. Requirements and Design Goals . . . . . . . . . . . . . . . . 4
	3. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5		3. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5
	4. Semantics . . . . . . . . . . . . . . . . . . . . . . . . . . 5		4. SenML Structure and Semantics . . . . . . . . . . . . . . . . 5
	5. Associating Meta-data . . . . . . . . . . . . . . . . . . . . 8		4.1. Base attributes . . . . . . . . . . . . . . . . . . . . . 5
	6. JSON Representation (application/senml+json) . . . . . . . . 8		4.2. Regular attributes . . . . . . . . . . . . . . . . . . . 6
	6.1. Examples . . . . . . . . . . . . . . . . . . . . . . . . 9		4.3. Considerations . . . . . . . . . . . . . . . . . . . . . 6
	6.1.1. Single Datapoint . . . . . . . . . . . . . . . . . . 9		4.4. Associating Meta-data . . . . . . . . . . . . . . . . . . 8
	6.1.2. Multiple Datapoints . . . . . . . . . . . . . . . . . 9		5. JSON Representation (application/senml+json) . . . . . . . . 8
	6.1.3. Multiple Measurements . . . . . . . . . . . . . . . . 10		5.1. Examples . . . . . . . . . . . . . . . . . . . . . . . . 9
	6.1.4. Collection of Resources . . . . . . . . . . . . . . . 11		5.1.1. Single Datapoint . . . . . . . . . . . . . . . . . . 9
	7. CBOR Representation (application/senml+cbor) . . . . . . . . 12		5.1.2. Multiple Datapoints . . . . . . . . . . . . . . . . . 9
	8. XML Representation (application/senml+xml) . . . . . . . . . 13		5.1.3. Multiple Measurements . . . . . . . . . . . . . . . . 11
	9. EXI Representation (application/senml-exi) . . . . . . . . . 15		5.1.4. Collection of Resources . . . . . . . . . . . . . . . 12
	10. Usage Considerations . . . . . . . . . . . . . . . . . . . . 19		6. CBOR Representation (application/senml+cbor) . . . . . . . . 12
	11. CDDL . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20		7. XML Representation (application/senml+xml) . . . . . . . . . 13
	12. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 21		8. EXI Representation (application/senml-exi) . . . . . . . . . 15
	12.1. Units Registry . . . . . . . . . . . . . . . . . . . . . 21		9. Usage Considerations . . . . . . . . . . . . . . . . . . . . 17
	12.2. SenML label registry . . . . . . . . . . . . . . . . . . 24		10. CDDL . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
	12.3. Media Type Registration . . . . . . . . . . . . . . . . 24		11. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 20
	12.3.1. senml+json Media Type Registration . . . . . . . . . 24		11.1. Units Registry . . . . . . . . . . . . . . . . . . . . . 20
	12.3.2. senml+cbor Media Type Registration . . . . . . . . . 25		11.2. SenML label registry . . . . . . . . . . . . . . . . . . 23
	12.3.3. senml+xml Media Type Registration . . . . . . . . . 26		11.3. Media Type Registration . . . . . . . . . . . . . . . . 24
	12.3.4. senml-exi Media Type Registration . . . . . . . . . 27		11.3.1. senml+json Media Type Registration . . . . . . . . . 24
	12.4. XML Namespace Registration . . . . . . . . . . . . . . . 28		11.3.2. senml+cbor Media Type Registration . . . . . . . . . 25
	12.5. CoAP Content-Format Registration . . . . . . . . . . . . 28		11.3.3. senml+xml Media Type Registration . . . . . . . . . 26
	13. Security Considerations . . . . . . . . . . . . . . . . . . . 28		11.3.4. senml-exi Media Type Registration . . . . . . . . . 27
	14. Privacy Considerations . . . . . . . . . . . . . . . . . . . 29		11.4. XML Namespace Registration . . . . . . . . . . . . . . . 28
	15. Acknowledgement . . . . . . . . . . . . . . . . . . . . . . . 29		11.5. CoAP Content-Format Registration . . . . . . . . . . . . 28
	16. References . . . . . . . . . . . . . . . . . . . . . . . . . 29		12. Security Considerations . . . . . . . . . . . . . . . . . . . 28
	16.1. Normative References . . . . . . . . . . . . . . . . . . 29		13. Privacy Considerations . . . . . . . . . . . . . . . . . . . 28
	16.2. Informative References . . . . . . . . . . . . . . . . . 30		14. Acknowledgement . . . . . . . . . . . . . . . . . . . . . . . 29
			15. References . . . . . . . . . . . . . . . . . . . . . . . . . 29
			15.1. Normative References . . . . . . . . . . . . . . . . . . 29
			15.2. Informative References . . . . . . . . . . . . . . . . . 30
	Appendix A. Links extension . . . . . . . . . . . . . . . . . . 31		Appendix A. Links extension . . . . . . . . . . . . . . . . . . 31
	Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 32		Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 31
	1. Overview		1. Overview
	Connecting sensors to the internet is not new, and there have been		Connecting sensors to the Internet is not new, and there have been
	many protocols designed to facilitate it. This specification defines		many protocols designed to facilitate it. This specification defines
	new media types for carrying simple sensor information in a protocol		new media types for carrying simple sensor information in a protocol
	such as HTTP or CoAP called the Sensor Markup Language (SenML). This		such as HTTP or CoAP. This format was designed so that processors
	format was designed so that processors with very limited capabilities		with very limited capabilities could easily encode a sensor
	could easily encode a sensor measurement into the media type, while		measurement into the media type, while at the same time a server
	at the same time a server parsing the data could relatively		parsing the data could relatively efficiently collect a large number
	efficiently collect a large number of sensor measurements. The		of sensor measurements. The markup language can be used for a
	markup language can be used for a variety of data flow models, most		variety of data flow models, most notably data feeds pushed from a
	notably data feeds pushed from a sensor to a collector, and the web		sensor to a collector, and the web resource model where the sensor is
	resource model where the sensor is requested as a resource		requested as a resource representation (e.g., "GET /sensor/
	representation (e.g., "GET /sensor/temperature").		temperature").
	There are many types of more complex measurements and measurements		There are many types of more complex measurements and measurements
	that this media type would not be suitable for. SenML strikes a		that this media type would not be suitable for. SenML strikes a
	balance between having some information about the sensor carried with		balance between having some information about the sensor carried with
	the sensor data so that the data is self describing but it also tries		the sensor data so that the data is self describing but it also tries
	to make that a fairly minimal set of auxiliary information for		to make that a fairly minimal set of auxiliary information for
	efficiency reason. Other information about the sensor can be		efficiency reason. Other information about the sensor can be
	discovered by other methods such as using the CoRE Link Format		discovered by other methods such as using the CoRE Link Format
	[RFC6690].		[RFC6690].
	skipping to change at page 3, line 45 ¶		skipping to change at page 3, line 51 ¶
	are defined for JSON [RFC7159], CBOR [RFC7049], XML, and Efficient		are defined for JSON [RFC7159], CBOR [RFC7049], XML, and Efficient
	XML Interchange (EXI) [W3C.REC-exi-20110310].		XML Interchange (EXI) [W3C.REC-exi-20110310].
	For example, the following shows a measurement from a temperature		For example, the following shows a measurement from a temperature
	gauge encoded in the JSON syntax.		gauge encoded in the JSON syntax.
	[{ "n": "urn:dev:ow:10e2073a01080063", "v":23.1, "u":"Cel" }]		[{ "n": "urn:dev:ow:10e2073a01080063", "v":23.1, "u":"Cel" }]
	In the example above, the array has a single SenML Record with a		In the example above, the array has a single SenML Record with a
	measurement for a sensor named "urn:dev:ow:10e2073a01080063" with a		measurement for a sensor named "urn:dev:ow:10e2073a01080063" with a
	current value of 23.5 degrees Celsius.		current value of 23.1 degrees Celsius.
	2. Requirements and Design Goals		2. Requirements and Design Goals
	The design goal is to be able to send simple sensor measurements in		The design goal is to be able to send simple sensor measurements in
	small packets on mesh networks from large numbers of constrained		small packets on mesh networks from large numbers of constrained
	devices. Keeping the total size of payload under 80 bytes makes this		devices. Keeping the total size of payload under 80 bytes makes this
	easy to use on a wireless mesh network. It is always difficult to		easy to use on a wireless mesh network. It is always difficult to
	define what small code is, but there is a desire to be able to		define what small code is, but there is a desire to be able to
	implement this in roughly 1 KB of flash on a 8 bit microprocessor.		implement this in roughly 1 KB of flash on a 8 bit microprocessor.
	Experience with Google power meter and large scale deployments has		Experience with Google power meter and large scale deployments has
	skipping to change at page 4, line 42 ¶		skipping to change at page 4, line 49 ¶
	elements in that record and any records that follow it. So a more		elements in that record and any records that follow it. So a more
	compact form of the example above is the following.		compact form of the example above is the following.
	[		[
	{ "bn": "urn:dev:ow:10e2073a01080063",		{ "bn": "urn:dev:ow:10e2073a01080063",
	"t": 1276020076, "v":23.5, "u":"Cel" },		"t": 1276020076, "v":23.5, "u":"Cel" },
	{ "t": 1276020091, "v":23.6, "u":"Cel" }		{ "t": 1276020091, "v":23.6, "u":"Cel" }
	]		]
	In the above example the Base Name is in the "bn" tag and the "n"		In the above example the Base Name is in the "bn" tag and the "n"
	tags in each Record are the empty string so they are omitted. The		tags in each Record are the empty string so they are omitted.
	Base Name also could be put in a separate Record such as in the
	following example.
	[
	{ "bn": "urn:dev:ow:10e2073a01080063" },
	{ "t": 1276020076, "v":23.5, "u":"Cel" },
	{ "t": 1276020091, "v":23.6, "u":"Cel" }
	]
	Some devices have accurate time while others do not so SenML supports		Some devices have accurate time while others do not so SenML supports
	absolute and relative times. Time is represented in floating point		absolute and relative times. Time is represented in floating point
	as seconds and values greater than zero represent an absolute time		as seconds and values greater than zero represent an absolute time
	relative to the unix epoch while values of 0 or less represent a		relative to the Unix epoch while values of 0 or less represent a
	relative time in the past from the current time. A simple sensor		relative time in the past from the current time. A simple sensor
	with no absolute wall clock time might take a measurement every		with no absolute wall clock time might take a measurement every
	second and batch up 60 of them then send it to a server. It would		second and batch up 60 of them then send it to a server. It would
	include the relative time the measurement was made to the time the		include the relative time the measurement was made to the time the
	batch was send in the SenML Pack. The server might have accurate NTP		batch was send in the SenML Pack. The server might have accurate NTP
	time and use the time it received the data, and the relative offset,		time and use the time it received the data, and the relative offset,
	to replace the times in the SenML with absolute times before saving		to replace the times in the SenML with absolute times before saving
	the SenML Pack in a document database.		the SenML Pack in a document database.
	3. Terminology		3. Terminology
	skipping to change at page 5, line 31 ¶		skipping to change at page 5, line 29 ¶
	"OPTIONAL" in this document are to be interpreted as described in		"OPTIONAL" in this document are to be interpreted as described in
	[RFC2119].		[RFC2119].
	This document also uses the following terms:		This document also uses the following terms:
	SenML Record: One measurement or configuration instance in time		SenML Record: One measurement or configuration instance in time
	presented using the SenML data model.		presented using the SenML data model.
	SenML Pack: One or more SenML Records in an array structure.		SenML Pack: One or more SenML Records in an array structure.
	4. Semantics		4. SenML Structure and Semantics
	Each SenML Pack carries a single array that represents a set of		Each SenML Pack carries a single array that represents a set of
	measurements and/or parameters. This array contains a series of		measurements and/or parameters. This array contains a series of
	objects with several optional attributes described below:		SenML Records with several attributes described below. There are two
			kind of attributes: base and regular. The base attributes can only
			be included in the first SenML Record and they apply to the entries
			in all Records. All base attributes are optional. Regular
			attributes can be included in any SenML Record and apply only to that
			Record.
			4.1. Base attributes
	Base Name: This is a string that is prepended to the names found in		Base Name: This is a string that is prepended to the names found in
	the entries. This attribute is optional. This applies to the		the entries.
	entries in all Records. A Base Name can only be included in the
	first Record of the array.
	Base Time: A base time that is added to the time found in an entry.		Base Time: A base time that is added to the time found in an entry.
	This attribute is optional. This applies to the entries in all
	Records. A Base Time can only be included in the first Record of
	the array.
	Base Unit: A base unit that is assumed for all entries, unless		Base Unit: A base unit that is assumed for all entries, unless
	otherwise indicated. This attribute is optional. If a record		otherwise indicated. If a record does not contain a unit value,
	does not contain a unit value, then the base unit is used		then the base unit is used. Otherwise the value of found in the
	otherwise the value of found in the Unit is used. This applies to		Unit is used.
	the entries in all Records. A Base Unit can only be included in
	the first object of the array.
	Base Value: A base value is added to the value found in an entry,		Base Value: A base value is added to the value found in an entry,
	similar to Base Time. This attribute is optional. This applies		similar to Base Time.
	to the entries in all Records. A Base Value can only be included
	in the first Record of the array.
	Version: Version number of media type format. This attribute is		Version: Version number of media type format. This attribute is an
	optional positive integer and defaults to 5 if not present. A		optional positive integer and defaults to 5 if not present. [RFC
	Version can only be included in the first object of the array.		Editor: change the default value to 10 when this specification is
			published as an RFC and remove this note]
			4.2. Regular attributes
	Name: Name of the sensor or parameter. When appended to the Base		Name: Name of the sensor or parameter. When appended to the Base
	Name attribute, this must result in a globally unique identifier		Name attribute, this must result in a globally unique identifier
	for the resource. The name is optional, if the Base Name is		for the resource. The name is optional, if the Base Name is
	present. If the name is missing, Base Name must uniquely identify		present. If the name is missing, Base Name must uniquely identify
	the resource. This can be used to represent a large array of		the resource. This can be used to represent a large array of
	measurements from the same sensor without having to repeat its		measurements from the same sensor without having to repeat its
	identifier on every measurement.		identifier on every measurement.
	Unit: Units for a measurement value. Optional. If the Record has		Unit: Units for a measurement value. Optional. If the Record has
	not Unit, the Base Unit is used as the Unit. Having no Unit and		no Unit, the Base Unit is used as the Unit. Having no Unit and no
	no Base Unit is allowed.		Base Unit is allowed.
	Value Value of the entry. Optional if a Sum value is present,		Value Value of the entry. Optional if a Sum value is present,
	otherwise required. Values are represented using three basic data		otherwise required. Values are represented using three basic data
	types, Floating point numbers ("v" field for "Value"), Booleans		types, Floating point numbers ("v" field for "Value"), Booleans
	("vb" for "Boolean Value"), Strings ("vs" for "String Value") and		("vb" for "Boolean Value"), Strings ("vs" for "String Value") and
	Data ("vd" for "Binary Data Value") . Exactly one of these three		Binary Data ("vd" for "Data Value") . Exactly one of these four
	fields MUST appear unless there is Sum field in which case it is		fields MUST appear unless there is Sum field in which case it is
	allowed to have no Value field or to have "v" field.		allowed to have no Value field or to have "v" field.
	Sum: Integrated sum of the values over time. Optional. This		Sum: Integrated sum of the values over time. Optional. This
	attribute is in the units specified in the Unit value multiplied		attribute is in the units specified in the Unit value multiplied
	by seconds.		by seconds.
	Time: Time when value was recorded. Optional.		Time: Time when value was recorded. Optional.
	Update Time: An optional time in seconds that represents the maximum		Update Time: An optional time in seconds that represents the maximum
	time before this sensor will provide an updated reading for a		time before this sensor will provide an updated reading for a
	measurement. This can be used to detect the failure of sensors or		measurement. This can be used to detect the failure of sensors or
	communications path from the sensor.		communications path from the sensor.
			4.3. Considerations
	The SenML format can be extended with further custom attributes.		The SenML format can be extended with further custom attributes.
	TODO - describe what extensions are possible and how to do them.		Both new base and regular attributes are allowed. See Section 11.2
			for details. Implementations MUST ignore attributes they don't
			recognize.
	Systems reading one of the objects MUST check for the Version		Systems reading one of the objects MUST check for the Version
	attribute. If this value is a version number larger than the version		attribute. If this value is a version number larger than the version
	which the system understands, the system SHOULD NOT use this object.		which the system understands, the system SHOULD NOT use this object.
	This allows the version number to indicate that the object contains		This allows the version number to indicate that the object contains
	mandatory to understand attributes. New version numbers can only be		mandatory to understand attributes. New version numbers can only be
	defined in an RFC that updates this specification or it successors.		defined in an RFC that updates this specification or it successors.
	The Name value is concatenated to the Base Name value to get the name		The Name value is concatenated to the Base Name value to get the name
	of the sensor. The resulting name needs to uniquely identify and		of the sensor. The resulting name needs to uniquely identify and
	skipping to change at page 8, line 5 ¶		skipping to change at page 8, line 7 ¶
	time and the measurement was made roughly "now". A negative value is		time and the measurement was made roughly "now". A negative value is
	used to indicate seconds in the past from roughly "now". A positive		used to indicate seconds in the past from roughly "now". A positive
	value is used to indicate the number of seconds, excluding leap		value is used to indicate the number of seconds, excluding leap
	seconds, since the start of the year 1970 in UTC.		seconds, since the start of the year 1970 in UTC.
	Representing the statistical characteristics of measurements, such as		Representing the statistical characteristics of measurements, such as
	accuracy, can be very complex. Future specification may add new		accuracy, can be very complex. Future specification may add new
	attributes to provide better information about the statistical		attributes to provide better information about the statistical
	properties of the measurement.		properties of the measurement.
	5. Associating Meta-data		A SenML object is referred to as "expanded" if it does not contain
			any base values and has no relative times.
			4.4. Associating Meta-data
	SenML is designed to carry the minimum dynamic information about		SenML is designed to carry the minimum dynamic information about
	measurements, and for efficiency reasons does not carry significant		measurements, and for efficiency reasons does not carry significant
	static meta-data about the device, object or sensors. Instead, it is		static meta-data about the device, object or sensors. Instead, it is
	assumed that this meta-data is carried out of band. For web		assumed that this meta-data is carried out of band. For web
	resources using SenML Packs, this meta-data can be made available		resources using SenML Packs, this meta-data can be made available
	using the CoRE Link Format [RFC6690]. The most obvious use of this		using the CoRE Link Format [RFC6690]. The most obvious use of this
	link format is to describe that a resource is available in a SenML		link format is to describe that a resource is available in a SenML
	format in the first place. The relevant media type indicator is		format in the first place. The relevant media type indicator is
	included in the Content-Type (ct=) attribute.		included in the Content-Type (ct=) attribute.
	6. JSON Representation (application/senml+json)		5. JSON Representation (application/senml+json)
	Record atributes:		The SenML labels (JSON object member names) shown in Table 1 are used
			in JSON SenML Record attributes.
	+---------------+------+---------+		+---------------+-------+---------+
	| SenML | JSON | Type |		| Name | label | Type |
	+---------------+------+---------+		+---------------+-------+---------+
	| Base Name | bn | String |		| Base Name | bn | String |
	| Base Time | bt | Number |		| Base Time | bt | Number |
	| Base Unit | bu | String |		| Base Unit | bu | String |
	| Base Value | bv | Number |		| Base Value | bv | Number |
	| Version | bver | Number |		| Version | bver | Number |
	| Name | n | String |		| Name | n | String |
	| Unit | u | String |		| Unit | u | String |
	| Value | v | Number |		| Value | v | Number |
	| String Value | vs | String |		| String Value | vs | String |
	| Boolean Value | vb | Boolean |		| Boolean Value | vb | Boolean |
	| Data Value | vd | String |		| Data Value | vd | String |
	| Value Sum | s | Number |		| Value Sum | s | Number |
	| Time | t | Number |		| Time | t | Number |
	| Update Time | ut | Number |		| Update Time | ut | Number |
	+---------------+------+---------+		+---------------+-------+---------+
	The root content consists of an array with JSON objects for each		Table 1: JSON SenML Labels
			The root content consists of an array with one JSON object for each
	SenML Record. All the fields in the above table MAY occur in the		SenML Record. All the fields in the above table MAY occur in the
	records with the type specified in the table.		records with the type specified in the table.
	Only the UTF-8 form of JSON is allowed. Characters in the String		Only the UTF-8 form of JSON is allowed. Characters in the String
	Value are encoded using the escape sequences defined in [RFC4627].		Value are encoded using the escape sequences defined in [RFC7159].
	Characters in the Data Value are base64 encoded with URL safe		Characters in the Data Value are base64 encoded with URL safe
	alphabet as defined in Section 5 of [RFC4648].		alphabet as defined in Section 5 of [RFC4648].
	Systems receiving measurements MUST be able to process the range of		Systems receiving measurements MUST be able to process the range of
	floating point numbers that are representable as an IEEE double-		floating point numbers that are representable as an IEEE double-
	precision floating-point numbers [IEEE.754.1985]. The number of		precision floating-point numbers [IEEE.754.1985]. The number of
	significant digits in any measurement is not relevant, so a reading		significant digits in any measurement is not relevant, so a reading
	of 1.1 has exactly the same semantic meaning as 1.10. If the value		of 1.1 has exactly the same semantic meaning as 1.10. If the value
	has an exponent, the "e" MUST be in lower case. The mantissa SHOULD		has an exponent, the "e" MUST be in lower case. The mantissa SHOULD
	be less than 19 characters long and the exponent SHOULD be less than		be less than 19 characters long and the exponent SHOULD be less than
	5 characters long. This allows time values to have better than micro		5 characters long. This allows time values to have better than micro
	second precision over the next 100 years.		second precision over the next 100 years.
	6.1. Examples		5.1. Examples
	TODO - Add example with string, data, boolean, and base value		TODO - Add example with string, data, boolean, and base value
	6.1.1. Single Datapoint		5.1.1. Single Datapoint
	The following shows a temperature reading taken approximately "now"		The following shows a temperature reading taken approximately "now"
	by a 1-wire sensor device that was assigned the unique 1-wire address		by a 1-wire sensor device that was assigned the unique 1-wire address
	of 10e2073a01080063:		of 10e2073a01080063:
	[{ "n": "urn:dev:ow:10e2073a01080063", "v":23.1, "u":"Cel" }]		[{ "n": "urn:dev:ow:10e2073a01080063", "v":23.1, "u":"Cel" }]
	6.1.2. Multiple Datapoints		5.1.2. Multiple Datapoints
	The following example shows voltage and current now, i.e., at an		The following example shows voltage and current now, i.e., at an
	unspecified time.		unspecified time.
	[{"bn": "urn:dev:ow:10e2073a01080063/"},		[ {"bn": "urn:dev:ow:10e2073a01080063",
	{ "n": "voltage", "t": 0, "u": "V", "v": 120.1 },		"n": "voltage", "t": 0, "u": "V", "v": 120.1 },
	{ "n": "current", "t": 0, "u": "A", "v": 1.2 }		{"n": "current", "t": 0, "u": "A", "v": 1.2 }
	]		]
	The next example is similar to the above one, but shows current at		The next example is similar to the above one, but shows current at
	Tue Jun 8 18:01:16 UTC 2010 and at each second for the previous 5		Tue Jun 8 18:01:16.001 UTC 2010 and at each second for the previous 5
	seconds.		seconds.
	[{"bn": "urn:dev:ow:10e2073a01080063/",		[{"bn": "urn:dev:ow:10e2073a01080063/",
	"bt": 1276020076.001,		"bt": 1276020076.001,
	"bu": "A",		"bu": "A",
	"bver": 5},		"bver": 5,
	{ "n": "voltage", "u": "V", "v": 120.1 },		"n": "voltage", "u": "V", "v": 120.1 },
	{ "n": "current", "t": -5, "v": 1.2 },		{ "n": "current", "t": -5, "v": 1.2 },
	{ "n": "current", "t": -4, "v": 1.30 },		{ "n": "current", "t": -4, "v": 1.30 },
	{ "n": "current", "t": -3, "v": 0.14e1 },		{ "n": "current", "t": -3, "v": 0.14e1 },
	{ "n": "current", "t": -2, "v": 1.5 },		{ "n": "current", "t": -2, "v": 1.5 },
	{ "n": "current", "t": -1, "v": 1.6 },		{ "n": "current", "t": -1, "v": 1.6 },
	{ "n": "current", "t": 0, "v": 1.7 }		{ "n": "current", "t": 0, "v": 1.7 }
	]		]
	Note that in some usage scenarios of SenML the implementations MAY		Note that in some usage scenarios of SenML the implementations MAY
	store or transmit SenML in a stream-like fashion, where data is		store or transmit SenML in a stream-like fashion, where data is
	collected over time and continuously added to the object. This mode		collected over time and continuously added to the object. This mode
	of operation is optional, but systems or protocols using SenML in		of operation is optional, but systems or protocols using SenML in
	this fashion MUST specify that they are doing this. SenML defines a		this fashion MUST specify that they are doing this. SenML defines a
	separate mime type (TODO) to indicate Sensor Streaming Markup		separate media type to indicate Sensor Streaming Markup Language
	Language (SensML) for this usage. In this situation the SensML		(SensML) for this usage (see Section 11.3.1). In this situation the
	stream can be sent and received in a partial fashion, i.e., a		SensML stream can be sent and received in a partial fashion, i.e., a
	measurement entry can be read as soon as the SenML Record is received		measurement entry can be read as soon as the SenML Record is received
	and not have to wait for the full SensML Stream to be complete.		and not have to wait for the full SensML Stream to be complete.
	For instance, the following stream of measurements may be sent via a		For instance, the following stream of measurements may be sent via a
	long lived HTTP POST from the producer of a SensML to the consumer of		long lived HTTP POST from the producer of a SensML to the consumer of
	that, and each measurement object may be reported at the time it		that, and each measurement object may be reported at the time it was
	measured:		measured:
	[ {"bn": "urn:dev:ow:10e2073a01080063",		[ {"bn": "urn:dev:ow:10e2073a01080063",
	"bt": 1320067464,		"bt": 1320067464,
	"bu": "%RH"},		"bu": "%RH",
	{ "v": 21.2, "t": 0 },		"v": 21.2, "t": 0 },
	{ "v": 21.3, "t": 10 },		{ "v": 21.3, "t": 10 },
	{ "v": 21.4, "t": 20 },		{ "v": 21.4, "t": 20 },
	{ "v": 21.4, "t": 30 },		{ "v": 21.4, "t": 30 },
	{ "v": 21.5, "t": 40 },		{ "v": 21.5, "t": 40 },
	{ "v": 21.5, "t": 50 },		{ "v": 21.5, "t": 50 },
	{ "v": 21.5, "t": 60 },		{ "v": 21.5, "t": 60 },
	{ "v": 21.6, "t": 70 },		{ "v": 21.6, "t": 70 },
	{ "v": 21.7, "t": 80 },		{ "v": 21.7, "t": 80 },
	{ "v": 21.5, "t": 90 },		{ "v": 21.5, "t": 90 },
	...		...
	6.1.3. Multiple Measurements		5.1.3. Multiple Measurements
	The following example shows humidity measurements from a mobile		The following example shows humidity measurements from a mobile
	device with an IPv6 address 2001:db8::1, starting at Mon Oct 31		device with a 1-wire address 10e2073a01080063, starting at Mon Oct 31
	13:24:24 UTC 2011. The device also provides position data, which is		13:24:24 UTC 2011. The device also provides position data, which is
	provided in the same measurement or parameter array as separate		provided in the same measurement or parameter array as separate
	entries. Note time is used to for correlating data that belongs		entries. Note time is used to for correlating data that belongs
	together, e.g., a measurement and a parameter associated with it.		together, e.g., a measurement and a parameter associated with it.
	Finally, the device also reports extra data about its battery status		Finally, the device also reports extra data about its battery status
	at a separate time.		at a separate time.
	[{"bn": "urn:dev:ow:10e2073a01080063",		[{"bn": "urn:dev:ow:10e2073a01080063",
	"bt": 1320067464,		"bt": 1320067464,
	"bu": "%RH"},		"bu": "%RH",
	{ "v": 20.0, "t": 0 },		"v": 20.0, "t": 0 },
	{ "v": 24.30621, "u": "lon", "t": 0 },		{ "v": 24.30621, "u": "lon", "t": 0 },
	{ "v": 60.07965, "u": "lat", "t": 0 },		{ "v": 60.07965, "u": "lat", "t": 0 },
	{ "v": 20.3, "t": 60 },		{ "v": 20.3, "t": 60 },
	{ "v": 24.30622, "u": "lon", "t": 60 },		{ "v": 24.30622, "u": "lon", "t": 60 },
	{ "v": 60.07965, "u": "lat", "t": 60 },		{ "v": 60.07965, "u": "lat", "t": 60 },
	{ "v": 20.7, "t": 120 },		{ "v": 20.7, "t": 120 },
	{ "v": 24.30623, "u": "lon", "t": 120 },		{ "v": 24.30623, "u": "lon", "t": 120 },
	{ "v": 60.07966, "u": "lat", "t": 120 },		{ "v": 60.07966, "u": "lat", "t": 120 },
	{ "v": 98.0, "u": "%EL", "t": 150 },		{ "v": 98.0, "u": "%EL", "t": 150 },
	{ "v": 21.2, "t": 180 },		{ "v": 21.2, "t": 180 },
	{ "v": 24.30628, "u": "lon", "t": 180 },		{ "v": 24.30628, "u": "lon", "t": 180 },
	{ "v": 60.07967, "u": "lat", "t": 180 }		{ "v": 60.07967, "u": "lat", "t": 180 }
	]		]
	The size of this example represented in various forms, as well as		The size of this example represented in various forms, as well as
	that form compressed with gzip is given in the following table.		that form compressed with gzip is given in the following table.
	+----------+------+-----------------+		+----------+------+-----------------+
	| Encoding | Size | Compressed Size |		| Encoding | Size | Compressed Size |
	+----------+------+-----------------+		+----------+------+-----------------+
	| JSON | 567 | 200 |		| JSON | 573 | 206 |
	| XML | 656 | 232 |		| XML | 649 | 235 |
	| CBOR | 292 | 192 |		| CBOR | 254 | 196 |
	| EXI | 160 | 183 |		| EXI | 173 | 196 |
	+----------+------+-----------------+		+----------+------+-----------------+
	Table 1: Size Comparisons		Table 2: Size Comparisons
	Note the CBOR and EXI sizes are not using the schema guidance so the		Note the EXI sizes are not using the schema guidance so the EXI
	could be a bit smaller.		representation could be a bit smaller.
	6.1.4. Collection of Resources		5.1.4. Collection of Resources
	The following example shows how to query one device that can provide		The following example shows how to query one device that can provide
	multiple measurements. The example assumes that a client has fetched		multiple measurements. The example assumes that a client has fetched
	information from a device at 2001:db8::2 by performing a GET		information from a device at 2001:db8::2 by performing a GET
	operation on http://[2001:db8::2] at Mon Oct 31 16:27:09 UTC 2011,		operation on http://[2001:db8::2] at Mon Oct 31 16:27:09 UTC 2011,
	and has gotten two separate values as a result, a temperature and		and has gotten two separate values as a result, a temperature and
	humidity measurement.		humidity measurement.
	[{"bn": "urn:dev:ow:10e2073a01080063/",		[{"bn": "http://[2001:db8::2]/",
	"bt": 1320078429,		"bt": 1320078429,
	"bver": 5		"bver": 5,
	},		"n": "temperature", "v": 27.2, "u": "Cel" },
	{ "n": "temperature", "v": 27.2, "u": "Cel" },
	{ "n": "humidity", "v": 80, "u": "%RH" }		{ "n": "humidity", "v": 80, "u": "%RH" }
	]		]
	7. CBOR Representation (application/senml+cbor)		6. CBOR Representation (application/senml+cbor)
	The CBOR [RFC7049] representation is equivalent to the JSON		The CBOR [RFC7049] representation is equivalent to the JSON
	representation, with the following changes:		representation, with the following changes:
	o For compactness, the CBOR representation uses integers for the map		o For compactness, the CBOR representation uses integers for the map
	keys defined in Table 2. This table is conclusive, i.e., there is		keys defined in Table 3. This table is conclusive, i.e., there is
	no intention to define any additional integer map keys; any		no intention to define any additional integer map keys; any
	extensions will use string map keys.		extensions will use string map keys.
	o For JSON Numbers, the CBOR representation can use integers,		o For JSON Numbers, the CBOR representation can use integers,
	floating point numbers, or decimal fractions (CBOR Tag 4); the		floating point numbers, or decimal fractions (CBOR Tag 4); the
	common limitations of JSON implementations are not relevant for		common limitations of JSON implementations are not relevant for
	these. For the version number, however, only an unsigned integer		these. For the version number, however, only an unsigned integer
	is allowed.		is allowed.
	+---------------+------------+------------+		+---------------+------------+------------+
	skipping to change at page 12, line 48 ¶		skipping to change at page 13, line 24 ¶
	| Units | u | 1 |		| Units | u | 1 |
	| Value | v | 2 |		| Value | v | 2 |
	| String Value | vs | 3 |		| String Value | vs | 3 |
	| Boolean Value | vb | 4 |		| Boolean Value | vb | 4 |
	| Value Sum | s | 5 |		| Value Sum | s | 5 |
	| Time | t | 6 |		| Time | t | 6 |
	| Update Time | ut | 7 |		| Update Time | ut | 7 |
	| Data Value | vd | 8 |		| Data Value | vd | 8 |
	+---------------+------------+------------+		+---------------+------------+------------+
	Table 2: CBOR representation: integers for map keys		Table 3: CBOR representation: integers for map keys
	The following example shows an hexdump of the CBOR example for the
	same sensor measurement as in Section 6.1.2.
	0000 88 a4 62 62 6e 78 1c 75 72 6e 3a 64 65 76 3a 6f |..bbnx.urn:dev:o|
	0010 77 3a 31 30 65 32 30 37 33 61 30 31 30 38 30 30 |w:10e2073a010800|
	0020 36 33 2f 62 62 74 fb 41 d3 03 a1 5b 00 10 62 62 |63/bbt.A...[..bb|
	0030 62 75 61 41 64 62 76 65 72 05 a3 61 6e 67 76 6f |buaAdbver..angvo|
	0040 6c 74 61 67 65 61 75 61 56 61 76 fb 40 5e 06 66 |ltageauaVav.@^.f|
	0050 66 66 66 66 a3 61 6e 67 63 75 72 72 65 6e 74 61 |ffff.angcurrenta|
	0060 74 fb c0 14 00 00 00 00 00 00 61 76 fb 3f f3 33 |t.........av.?.3|
	0070 33 33 33 33 33 a3 61 6e 67 63 75 72 72 65 6e 74 |33333.angcurrent|
	0080 61 74 fb c0 10 00 00 00 00 00 00 61 76 fb 3f f4 |at.........av.?.|
	0090 cc cc cc cc cc cd a3 61 6e 67 63 75 72 72 65 6e |.......angcurren|
	00a0 74 61 74 fb c0 08 00 00 00 00 00 00 61 76 fb 3f |tat.........av.?|
	00b0 f6 66 66 66 66 66 66 a3 61 6e 67 63 75 72 72 65 |.ffffff.angcurre|
	00c0 6e 74 61 74 fb c0 00 00 00 00 00 00 00 61 76 fb |ntat.........av.|
	00d0 3f f8 00 00 00 00 00 00 a3 61 6e 67 63 75 72 72 |?........angcurr|
	00e0 65 6e 74 61 74 fb bf f0 00 00 00 00 00 00 61 76 |entat.........av|
	00f0 fb 3f f9 99 99 99 99 99 9a a2 61 6e 67 63 75 72 |.?........angcur|
	0100 72 65 6e 74 61 76 fb 3f fb 33 33 33 33 33 33 |rentav.?.333333|
	010f
	8. XML Representation (application/senml+xml)		The following example shows a dump of the CBOR example for the same
			sensor measurement as in Section 5.1.2.
	A SenML Stream can also be represented in XML format as defined in		7. XML Representation (application/senml+xml)
	this section. The following example shows an XML example for the
	same sensor measurement as in Section 6.1.2.
	<sensml xmlns="urn:ietf:params:xml:ns:senml">		A SenML Pack or Stream can also be represented in XML format as
	<senml bn="urn:dev:ow:10e2073a01080063/" bt="1.276020076001e+09"		defined in this section. The following example shows an XML example
	bu="A" bver="5"></senml>		for the same sensor measurement as in Section 5.1.2.
	<senml n="voltage" u="V" v="120.1"></senml>
	<senml n="current" t="-5" v="1.2"></senml>
	<senml n="current" t="-4" v="1.3"></senml>
	<senml n="current" t="-3" v="1.4"></senml>
	<senml n="current" t="-2" v="1.5"></senml>
	<senml n="current" t="-1" v="1.6"></senml>
	<senml n="current" v="1.7"></senml>
	</sensml>
	The SenML Stream is represented as a sensml tag that contains a		The SenML Stream is represented as a sensml tag that contains a
	series of senml tags for each SenML Record. The SenML Fields are		series of senml tags for each SenML Record. The SenML Fields are
	represents as XML attributes. The following table shows the mapping		represents as XML attributes. The following table shows the mapping
	the SenML Field names to the attribute used in the XML senml tag.		of the SenML labels to the attribute names and types used in the XML
			senml tags.
	+---------------+------+---------+		+---------------+------+---------+
	| SenML Field | XML | Type |		| Name | XML | Type |
	+---------------+------+---------+		+---------------+------+---------+
	| Base Name | bn | string |		| Base Name | bn | string |
	| Base Time | bt | double |		| Base Time | bt | double |
	| Base Unit | bu | string |		| Base Unit | bu | string |
	| Base Value | bv | double |		| Base Value | bv | double |
	| Base Version | bver | int |		| Base Version | bver | int |
	| Name | n | string |		| Name | n | string |
	| Unit | u | string |		| Unit | u | string |
	| Value | v | double |		| Value | v | double |
	| String Value | vs | string |		| String Value | vs | string |
	| Data Value | vd | string |		| Data Value | vd | string |
	| Boolean Value | vb | boolean |		| Boolean Value | vb | boolean |
	| Value Sum | s | double |		| Value Sum | s | double |
	| Time | t | double |		| Time | t | double |
	| Update Time | ut | double |		| Update Time | ut | double |
	+---------------+------+---------+		+---------------+------+---------+
			Table 4: XML SenML Labels
	The RelaxNG schema for the XML is:		The RelaxNG schema for the XML is:
	default namespace = "urn:ietf:params:xml:ns:senml"		default namespace = "urn:ietf:params:xml:ns:senml"
	namespace rng = "http://relaxng.org/ns/structure/1.0"		namespace rng = "http://relaxng.org/ns/structure/1.0"
	link = element l {
	attribute * { xsd:string }*
	}
	senml = element senml {		senml = element senml {
	attribute bn { xsd:string }?,		attribute bn { xsd:string }?,
	attribute bt { xsd:double }?,		attribute bt { xsd:double }?,
	attribute bv { xsd:double }?,		attribute bv { xsd:double }?,
	attribute bu { xsd:string }?,		attribute bu { xsd:string }?,
	attribute bver { xsd:int }?,		attribute bver { xsd:int }?,
	attribute n { xsd:string }?,		attribute n { xsd:string }?,
	attribute s { xsd:double }?,		attribute s { xsd:double }?,
	attribute t { xsd:double }?,		attribute t { xsd:double }?,
	attribute u { xsd:string }?,		attribute u { xsd:string }?,
	attribute ut { xsd:double }?,		attribute ut { xsd:double }?,
	attribute v { xsd:double }?,		attribute v { xsd:double }?,
	attribute vb { xsd:boolean }?,		attribute vb { xsd:boolean }?,
	attribute vs { xsd:string }?,		attribute vs { xsd:string }?,
	attribute vd { xsd:string }?,		attribute vd { xsd:string }?,
	link*		attribute l { xsd:string }?
	}		}
	sensml =		sensml =
	element sensml {		element sensml {
	senml+		senml+
	}		}
	start = sensml		start = sensml
	9. EXI Representation (application/senml-exi)		8. EXI Representation (application/senml-exi)
	For efficient transmission of SenML over e.g. a constrained network,		For efficient transmission of SenML over e.g. a constrained network,
	Efficient XML Interchange (EXI) can be used. This encodes the XML		Efficient XML Interchange (EXI) can be used. This encodes the XML
	Schema structure of SenML into binary tags and values rather than		Schema structure of SenML into binary tags and values rather than
	ASCII text. An EXI representation of SenML SHOULD be made using the		ASCII text. An EXI representation of SenML SHOULD be made using the
	strict schema-mode of EXI. This mode however does not allow tag		strict schema-mode of EXI. This mode however does not allow tag
	extensions to the schema, and therefore any extensions will be lost		extensions to the schema, and therefore any extensions will be lost
	in the encoding. For uses where extensions need to be preserved in		in the encoding. For uses where extensions need to be preserved in
	EXI, the non-strict schema mode of EXI MAY be used.		EXI, the non-strict schema mode of EXI MAY be used.
	skipping to change at page 17, line 10 ¶		skipping to change at page 16, line 17 ¶
	TODO - examples probably have the wrong setting the schemaID		TODO - examples probably have the wrong setting the schemaID
	The following is the XSD Schema to be used for strict schema guided		The following is the XSD Schema to be used for strict schema guided
	EXI processing. It is generated from the RelaxNG.		EXI processing. It is generated from the RelaxNG.
	<?xml version="1.0" encoding="utf-8"?>		<?xml version="1.0" encoding="utf-8"?>
	<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"		<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
	elementFormDefault="qualified"		elementFormDefault="qualified"
	targetNamespace="urn:ietf:params:xml:ns:senml"		targetNamespace="urn:ietf:params:xml:ns:senml"
	xmlns:ns1="urn:ietf:params:xml:ns:senml">		xmlns:ns1="urn:ietf:params:xml:ns:senml">
	<xs:element name="l">
	<xs:complexType>
	<xs:anyAttribute processContents="skip" />
	</xs:complexType>
	</xs:element>
	<xs:element name="senml">		<xs:element name="senml">
	<xs:complexType>		<xs:complexType>
	<xs:sequence>
	<xs:element minOccurs="0" maxOccurs="unbounded"
	ref="ns1:l" />
	</xs:sequence>
	<xs:attribute name="bn" type="xs:string" />		<xs:attribute name="bn" type="xs:string" />
	<xs:attribute name="bt" type="xs:double" />		<xs:attribute name="bt" type="xs:double" />
	<xs:attribute name="bv" type="xs:double" />		<xs:attribute name="bv" type="xs:double" />
	<xs:attribute name="bu" type="xs:string" />		<xs:attribute name="bu" type="xs:string" />
	<xs:attribute name="bver" type="xs:int" />		<xs:attribute name="bver" type="xs:int" />
	<xs:attribute name="n" type="xs:string" />		<xs:attribute name="n" type="xs:string" />
	<xs:attribute name="s" type="xs:double" />		<xs:attribute name="s" type="xs:double" />
	<xs:attribute name="t" type="xs:double" />		<xs:attribute name="t" type="xs:double" />
	<xs:attribute name="u" type="xs:string" />		<xs:attribute name="u" type="xs:string" />
	<xs:attribute name="ut" type="xs:double" />		<xs:attribute name="ut" type="xs:double" />
	<xs:attribute name="v" type="xs:double" />		<xs:attribute name="v" type="xs:double" />
	<xs:attribute name="vb" type="xs:boolean" />		<xs:attribute name="vb" type="xs:boolean" />
	<xs:attribute name="vs" type="xs:string" />		<xs:attribute name="vs" type="xs:string" />
	<xs:attribute name="vd" type="xs:string" />		<xs:attribute name="vd" type="xs:string" />
			<xs:attribute name="l" type="xs:string" />
	</xs:complexType>		</xs:complexType>
	</xs:element>		</xs:element>
	<xs:element name="sensml">		<xs:element name="sensml">
	<xs:complexType>		<xs:complexType>
	<xs:sequence>		<xs:sequence>
	<xs:element maxOccurs="unbounded" ref="ns1:senml" />		<xs:element maxOccurs="unbounded" ref="ns1:senml" />
	</xs:sequence>		</xs:sequence>
	</xs:complexType>		</xs:complexType>
	</xs:element>		</xs:element>
	</xs:schema>		</xs:schema>
	The following shows a hexdump of the EXI produced from encoding the		The following shows a hexdump of the EXI produced from encoding the
	following XML example. Note this example is the same information as		following XML example. Note this example is the same information as
	the first example in Section 6.1.2 in JSON format.		the first example in Section 5.1.2 in JSON format.
	<sensml xmlns="urn:ietf:params:xml:ns:senml">
	<senml bn="urn:dev:ow:10e2073a01080063/"></senml>
	<senml n="voltage" u="V" v="120.1"></senml>
	<senml n="current" u="A" v="1.2"></senml>
	</sensml>
	Which compresses with EXI to the following displayed in hexdump:		Which compresses with EXI to the following displayed in hexdump:
	0000 a0 30 3d cd 95 b9 b5 b0 b9 9d 95 b8 b9 e1 cd 91 |.0=.............|		0000 a0 30 3d cd 95 b9 b5 b0 b9 9d 95 b8 b9 e1 cd 90 |.0=.............|
	0010 00 f3 ab 93 71 d3 23 2b b1 d3 7b b9 d1 89 83 29 |....q.#+..{....)|		0010 80 eb ab 93 71 d3 23 2b b1 d3 7b b9 d1 89 83 29 |....q.#+..{....)|
	0020 91 81 b9 9b 09 81 89 81 c1 81 81 b1 99 7f 14 25 |...............%|		0020 91 81 b9 9b 09 81 89 81 c1 81 81 b1 9a 84 bb 37 |...............7|
	0030 d9 bd b1 d1 85 9d 94 80 d5 8a c4 26 01 0a 12 c6 |...........&....|		0030 b6 3a 30 b3 b2 90 1a b1 58 84 c0 33 04 b1 ba b9 |.:0.....X..3....|
	0040 ea e4 e4 ca dc e8 40 68 24 19 00 90 |......@h$...|		0040 39 32 b7 3a 10 1a 09 06 40 38 |92.:....@8|
	004c		004a
	The above example used the bit packed form of EXI but it is also		The above example used the bit packed form of EXI but it is also
	possible to use a byte packed form of EXI which can makes it easier		possible to use a byte packed form of EXI which can makes it easier
	for a simple sensor to produce valid EXI without really implementing		for a simple sensor to produce valid EXI without really implementing
	EXI. Consider the example of a temperature sensor that produces a		EXI. Consider the example of a temperature sensor that produces a
	value in tenths of degrees Celsius over a range of 0.0 to 55.0. It		value in tenths of degrees Celsius over a range of 0.0 to 55.0. It
	would produce an XML SenML file such as:		would produce an XML SenML file such as:
	<sensml xmlns="urn:ietf:params:xml:ns:senml">
	<senml n="urn:dev:ow:10e2073a01080063" u="Cel" v="23.1"></senml>
	</sensml>
	The compressed form, using the byte alignment option of EXI, for the		The compressed form, using the byte alignment option of EXI, for the
	above XML is the following:		above XML is the following:
	0000 a0 00 48 81 ee 6c ad cd ad 85 cc ec ad c5 cf 0e |..H..l..........|		0000 a0 00 48 81 ee 6c ad cd ad 85 cc ec ad c5 cf 0e |..H..l..........|
	0010 6c 80 02 05 1d 75 72 6e 3a 64 65 76 3a 6f 77 3a |l....urn:dev:ow:|		0010 6c 80 01 06 1d 75 72 6e 3a 64 65 76 3a 6f 77 3a |l....urn:dev:ow:|
	0020 31 30 65 32 30 37 33 61 30 31 30 38 30 30 36 33 |10e2073a01080063|		0020 31 30 65 32 30 37 33 61 30 31 30 38 30 30 36 33 |10e2073a01080063|
	0030 02 05 43 65 6c 01 00 e7 01 01 00 04 01 |..Cel........|		0030 02 05 43 65 6c 01 00 e7 01 01 00 03 01 |..Cel........|
	003d		003d
	A small temperature sensor devices that only generates this one EXI		A small temperature sensor devices that only generates this one EXI
	file does not really need an full EXI implementation. It can simple		file does not really need an full EXI implementation. It can simply
	hard code the output replacing the one wire device ID starting at		hard code the output replacing the 1-wire device ID starting at byte
	byte 0x16 and going to byte 0x31 with it's device ID, and replacing		0x20 and going to byte 0x2F with it's device ID, and replacing the
	the value "0xe7 0x01" at location 0x38 to 0x39 with the current		value "0xe7 0x01" at location 0x37 and 0x38 with the current
	temperature. The EXI Specification [W3C.REC-exi-20110310] contains		temperature. The EXI Specification [W3C.REC-exi-20110310] contains
	the full information 'on how floating point numbers are represented,		the full information 'on how floating point numbers are represented,
	but for the purpose of this sensor, the temperature can be converted		but for the purpose of this sensor, the temperature can be converted
	to an integer in tenths of degrees (231 in this example). EXI stores		to an integer in tenths of degrees (231 in this example). EXI stores
	7 bits of the integer in each byte with the top bit set to one if		7 bits of the integer in each byte with the top bit set to one if
	there are further bytes. So the first bytes at is set to low 7 bits		there are further bytes. So the first bytes at is set to low 7 bits
	of the integer temperature in tenths of degrees plus 0x80. In this		of the integer temperature in tenths of degrees plus 0x80. In this
	example 231 & 0x7F + 0x80 = 0xE7. The second byte is set to the		example 231 & 0x7F + 0x80 = 0xE7. The second byte is set to the
	integer temperature in tenths of degrees right shifted 7 bits. In		integer temperature in tenths of degrees right shifted 7 bits. In
	this example 231 >> 7 = 0x01.		this example 231 >> 7 = 0x01.
	10. Usage Considerations		9. Usage Considerations
	The measurements support sending both the current value of a sensor		The measurements support sending both the current value of a sensor
	as well as the an integrated sum. For many types of measurements,		as well as the an integrated sum. For many types of measurements,
	the sum is more useful than the current value. For example, an		the sum is more useful than the current value. For example, an
	electrical meter that measures the energy a given computer uses will		electrical meter that measures the energy a given computer uses will
	typically want to measure the cumulative amount of energy used. This		typically want to measure the cumulative amount of energy used. This
	is less prone to error than reporting the power each second and		is less prone to error than reporting the power each second and
	trying to have something on the server side sum together all the		trying to have something on the server side sum together all the
	power measurements. If the network between the sensor and the meter		power measurements. If the network between the sensor and the meter
	goes down over some period of time, when it comes back up, the		goes down over some period of time, when it comes back up, the
	skipping to change at page 20, line 7 ¶		skipping to change at page 18, line 43 ¶
	3. Applications cannot make assumptions about when the device		3. Applications cannot make assumptions about when the device
	started accumulating values into the sum.		started accumulating values into the sum.
	Typically applications can make some assumptions about specific		Typically applications can make some assumptions about specific
	sensors that will allow them to deal with these problems. A common		sensors that will allow them to deal with these problems. A common
	assumption is that for sensors whose measurement values are always		assumption is that for sensors whose measurement values are always
	positive, the sum should never get smaller; so if the sum does get		positive, the sum should never get smaller; so if the sum does get
	smaller, the application will know that one of the situations listed		smaller, the application will know that one of the situations listed
	above has happened.		above has happened.
	11. CDDL		10. CDDL
	For reference, the CBOR representation can be described with the CDDL		For reference, the JSON and CBOR representations can be described
	[I-D.greevenbosch-appsawg-cbor-cddl] specification in Figure 1.		with the common CDDL [I-D.greevenbosch-appsawg-cbor-cddl]
			specification in Figure 1.
	SenML-Pack = [initial-record, * follow-on-record]		SenML-Pack = [initial-record, * follow-on-record]
	initial-record = initial-defined .and initial-generic		initial-record = initial-defined .and initial-generic
	follow-on-record = follow-on-defined .and follow-on-generic		follow-on-record = follow-on-defined .and follow-on-generic
	; first do a specification of the labels as defined:		; first do a specification of the labels as defined:
	initial-defined = {		initial-defined = {
	? bn => tstr, ; Base Name		? bn => tstr, ; Base Name
	skipping to change at page 20, line 32 ¶		skipping to change at page 19, line 21 ¶
	? bu => tstr, ; Base Units		? bu => tstr, ; Base Units
	? bv => numeric, ; Base value		? bv => numeric, ; Base value
	? bver => uint, ; Base Version		? bver => uint, ; Base Version
	follow-on-defined-group,		follow-on-defined-group,
	+ base-key-value-pair		+ base-key-value-pair
	}		}
	follow-on-defined-group = (		follow-on-defined-group = (
	? n => tstr, ; Name		? n => tstr, ; Name
	? u => tstr, ; Units		? u => tstr, ; Units
	? ( v => numeric // ; Numeric Value
	vs => tstr // ; String Value
	vb => bool // ; Boolean Value
	vd => bstr ) ; Data Value
	? s => numeric, ; Value Sum		? s => numeric, ; Value Sum
	? t => numeric, ; Time		? t => numeric, ; Time
	? ut => numeric, ; Update Time		? ut => numeric, ; Update Time
	* key-value-pair		* key-value-pair,
			? ( v => numeric // ; Numeric Value
			vs => tstr // ; String Value
			vb => bool // ; Boolean Value
			vd => binary-value ) ; Data Value
	)		)
	follow-on-defined = { follow-on-defined-group }		follow-on-defined = { follow-on-defined-group }
	; CBOR version (use the labels)
	bver = -1 n = 0 s = 5
	bn = -2 u = 1 t = 6
	bt = -3 v = 2 ut = 7
	bu = -4 vs = 3 vd = 8
	bv = -5 vb = 4
	; use the label *names* for JSON
	; now define the generic versions		; now define the generic versions
	initial-generic = {		initial-generic = {
	follow-on-generic-group,		follow-on-generic-group,
	* base-key-value-pair,		* base-key-value-pair,
	}		}
	follow-on-generic-group = (		follow-on-generic-group = (
	+ key-value-pair,		+ key-value-pair,
	)		)
	follow-on-generic = { follow-on-generic-group }		follow-on-generic = { follow-on-generic-group }
	skipping to change at page 21, line 21 ¶		skipping to change at page 19, line 51 ¶
	)		)
	follow-on-generic = { follow-on-generic-group }		follow-on-generic = { follow-on-generic-group }
	key-value-pair = ( non-b-label => value )		key-value-pair = ( non-b-label => value )
	base-key-value-pair = ( b-label => value )		base-key-value-pair = ( b-label => value )
	non-b-label = tstr .regexp "[A-Zac-z0-9][-_:.A-Za-z0-9]*" / uint		non-b-label = tstr .regexp "[A-Zac-z0-9][-_:.A-Za-z0-9]*" / uint
	b-label = tstr .regexp "b[-_:.A-Za-z0-9]+" / nint		b-label = tstr .regexp "b[-_:.A-Za-z0-9]+" / nint
	value = tstr / bstr / numeric / bool		value = tstr / binary-value / numeric / bool
	numeric = number / decfrac		numeric = number / decfrac
	Figure 1: CDDL specification for CBOR SenML		Figure 1: Common CDDL specification for CBOR and JSON SenML
	TODO - seems to be a problem with CDDL not validating examples		For JSON, we use text labels and base64url-encoded binary data
			(Figure 2).
	12. IANA Considerations		bver = "bver" n = "n" s = "s"
			bn = "bn" u = "u" t = "t"
			bt = "bt" v = "v" ut = "ut"
			bu = "bu" vs = "vs" vd = "vd"
			bv = "bv" vb = "vb"
			binary-value = tstr ; base64url encoded
			Figure 2: JSON-specific CDDL specification for SenML
			For CBOR, we use integer labels and native binary data (Figure 3).
			bver = -1 n = 0 s = 5
			bn = -2 u = 1 t = 6
			bt = -3 v = 2 ut = 7
			bu = -4 vs = 3 vd = 8
			bv = -5 vb = 4
			binary-value = bstr
			Figure 3: CBOR-specific CDDL specification for SenML
			11. IANA Considerations
	Note to RFC Editor: Please replace all occurrences of "RFC-AAAA" with		Note to RFC Editor: Please replace all occurrences of "RFC-AAAA" with
	the RFC number of this specification.		the RFC number of this specification.
	12.1. Units Registry		11.1. Units Registry
	IANA will create a registry of SenML unit symbols. The primary		IANA will create a registry of SenML unit symbols. The primary
	purpose of this registry is to make sure that symbols uniquely map to		purpose of this registry is to make sure that symbols uniquely map to
	give type of measurement. Definitions for many of these units can be		give type of measurement. Definitions for many of these units can be
	found in location such as [NIST811] and [BIPM].		found in location such as [NIST811] and [BIPM]. Units marked with an
			asterisk are NOT RECOMMENDED to be produced by new implementations,
			but are in active use and SHOULD be implemented by consumers that can
			use the related base units.
	+--------+--------------------------------------+-------+-----------+		+----------+------------------------------------+-------+-----------+
	| Symbol | Description | Type | Reference |		| Symbol | Description | Type | Reference |
	+--------+--------------------------------------+-------+-----------+		+----------+------------------------------------+-------+-----------+
	| m | meter | float | RFC-AAAA |		| m | meter | float | RFC-AAAA |
	| g | gram | float | RFC-AAAA |		| kg | kilogram | float | RFC-AAAA |
	| s | second | float | RFC-AAAA |		| g | gram* | float | RFC-AAAA |
	| A | ampere | float | RFC-AAAA |		| s | second | float | RFC-AAAA |
	| K | kelvin | float | RFC-AAAA |		| A | ampere | float | RFC-AAAA |
	| cd | candela | float | RFC-AAAA |		| K | kelvin | float | RFC-AAAA |
	| mol | mole | float | RFC-AAAA |		| cd | candela | float | RFC-AAAA |
	| Hz | hertz | float | RFC-AAAA |		| mol | mole | float | RFC-AAAA |
	| rad | radian | float | RFC-AAAA |		| Hz | hertz | float | RFC-AAAA |
	| sr | steradian | float | RFC-AAAA |		| rad | radian | float | RFC-AAAA |
	| N | newton | float | RFC-AAAA |		| sr | steradian | float | RFC-AAAA |
	| Pa | pascal | float | RFC-AAAA |		| N | newton | float | RFC-AAAA |
	| J | joule | float | RFC-AAAA |		| Pa | pascal | float | RFC-AAAA |
	| W | watt | float | RFC-AAAA |		| J | joule | float | RFC-AAAA |
	| C | coulomb | float | RFC-AAAA |		| W | watt | float | RFC-AAAA |
	| V | volt | float | RFC-AAAA |		| C | coulomb | float | RFC-AAAA |
	| F | farad | float | RFC-AAAA |		| V | volt | float | RFC-AAAA |
	| Ohm | ohm | float | RFC-AAAA |		| F | farad | float | RFC-AAAA |
	| S | siemens | float | RFC-AAAA |		| Ohm | ohm | float | RFC-AAAA |
	| Wb | weber | float | RFC-AAAA |		| S | siemens | float | RFC-AAAA |
	| T | tesla | float | RFC-AAAA |		| Wb | weber | float | RFC-AAAA |
	| H | henry | float | RFC-AAAA |		| T | tesla | float | RFC-AAAA |
	| Cel | degrees Celsius | float | RFC-AAAA |		| H | henry | float | RFC-AAAA |
	| lm | lumen | float | RFC-AAAA |		| Cel | degrees Celsius | float | RFC-AAAA |
	| lx | lux | float | RFC-AAAA |		| lm | lumen | float | RFC-AAAA |
	| Bq | becquerel | float | RFC-AAAA |		| lx | lux | float | RFC-AAAA |
	| Gy | gray | float | RFC-AAAA |		| Bq | becquerel | float | RFC-AAAA |
	| Sv | sievert | float | RFC-AAAA |		| Gy | gray | float | RFC-AAAA |
	| kat | katal | float | RFC-AAAA |		| Sv | sievert | float | RFC-AAAA |
	| pH | pH acidity | float | RFC-AAAA |		| kat | katal | float | RFC-AAAA |
	| % | Value of a switch (note 1) | float | RFC-AAAA |		| m2 | square meter (area) | float | RFC-AAAA |
	| count | counter value | float | RFC-AAAA |		| m3 | cubic meter (volume) | float | RFC-AAAA |
	| %RH | Relative Humidity | float | RFC-AAAA |		| l | liter (volume)* | float | RFC-AAAA |
	| m2 | area | float | RFC-AAAA |		| m/s | meter per second (velocity) | float | RFC-AAAA |
	| l | volume in liters | float | RFC-AAAA |		| m/s2 | meter per square second | float | RFC-AAAA |
	| m/s | velocity | float | RFC-AAAA |		| | (acceleration) | | |
	| m/s2 | acceleration | float | RFC-AAAA |		| m3/s | cubic meter per second (flow rate) | float | RFC-AAAA |
	| l/s | flow rate in liters per second | float | RFC-AAAA |		| l/s | liter per second (flow rate)* | float | RFC-AAAA |
	| W/m2 | irradiance | float | RFC-AAAA |		| W/m2 | watt per square meter (irradiance) | float | RFC-AAAA |
	| cd/m2 | luminance | float | RFC-AAAA |		| cd/m2 | candela per square meter | float | RFC-AAAA |
	| Bspl | bel sound pressure level | float | RFC-AAAA |		| | (luminance) | | |
	| bit/s | bits per second | float | RFC-AAAA |		| bit | bit (information content) | float | RFC-AAAA |
	| lat | degrees latitude (note 2) | float | RFC-AAAA |		| bit/s | bit per second (data rate) | float | RFC-AAAA |
	| lon | degrees longitude (note 2) | float | RFC-AAAA |		| lat | degrees latitude (note 2) | float | RFC-AAAA |
	| %EL | remaining battery energy level in | float | RFC-AAAA |		| lon | degrees longitude (note 2) | float | RFC-AAAA |
	| | percents | | |		| pH | pH value (acidity; logarithmic | float | RFC-AAAA |
	| EL | remaining battery energy level in | float | RFC-AAAA |		| | quantity) | | |
	| | seconds | | |		| dB | decibel (logarithmic quantity) | float | RFC-AAAA |
	| beat/m | Heart rate in beats per minute | float | RFC-AAAA |		| Bspl | bel (sound pressure level; | float | RFC-AAAA |
	| beats | Cumulative number of heart beats | float | RFC-AAAA |		| | logarithmic quantity)* | | |
	+--------+--------------------------------------+-------+-----------+		| count | 1 (counter value) | float | RFC-AAAA |
			| / | 1 (Ratio e.g., value of a switch, | float | RFC-AAAA |
			| | note 1) | | |
			| % | 1 (Ratio e.g., value of a switch, | float | RFC-AAAA |
			| | note 1)* | | |
			| %RH | Percentage (Relative Humidity) | float | RFC-AAAA |
			| %EL | Percentage (remaining battery | float | RFC-AAAA |
			| | energy level) | | |
			| EL | seconds (remaining battery energy | float | RFC-AAAA |
			| | level) | | |
			| 1/s | 1 per second (event rate) | float | RFC-AAAA |
			| 1/min | 1 per minute (event rate, "rpm")* | float | RFC-AAAA |
			| beat/min | 1 per minute (Heart rate in beats | float | RFC-AAAA |
			| | per minute)* | | |
			| beats | 1 (Cumulative number of heart | float | RFC-AAAA |
			| | beats)* | | |
			+----------+------------------------------------+-------+-----------+
	Table 3		Table 5
	o Note 1: A value of 0.0 indicates the switch is off while 1.0		o Note 1: A value of 0.0 indicates the switch is off while 1.0
	indicates on and 0.5 would be half on.		indicates on and 0.5 would be half on. The preferred name of this
			unit is "/". For historical reasons, the name "%" is also
			provided for the same unit - but note that while that name
			strongly suggests a percentage (0..100) -- it is however NOT a
			percentage, but the absolute ratio!
	o Note 2: Assumed to be in WGS84 unless another reference frame is		o Note 2: Assumed to be in WGS84 unless another reference frame is
	known for the sensor.		known for the sensor.
	New entries can be added to the registration by either Expert Review		New entries can be added to the registration by either Expert Review
	or IESG Approval as defined in [RFC5226]. Experts should exercise		or IESG Approval as defined in [RFC5226]. Experts should exercise
	their own good judgment but need to consider the following		their own good judgment but need to consider the following
	guidelines:		guidelines:
	1. There needs to be a real and compelling use for any new unit to		1. There needs to be a real and compelling use for any new unit to
	skipping to change at page 23, line 28 ¶		skipping to change at page 23, line 7 ¶
	be used in different real-life contexts. For example, degrees		be used in different real-life contexts. For example, degrees
	when measuring latitude have no semantic relation to degrees		when measuring latitude have no semantic relation to degrees
	when measuring temperature; thus two different units are needed.		when measuring temperature; thus two different units are needed.
	3. These measurements are produced by computers for consumption by		3. These measurements are produced by computers for consumption by
	computers. The principle is that conversion has to be easily be		computers. The principle is that conversion has to be easily be
	done when both reading and writing the media type. The value of		done when both reading and writing the media type. The value of
	a single canonical representation outweighs the convenience of		a single canonical representation outweighs the convenience of
	easy human representations or loss of precision in a conversion.		easy human representations or loss of precision in a conversion.
	4. Use of SI prefixes such as "k" before the unit is not allowed.		4. Use of SI prefixes such as "k" before the unit is not
	Instead one can represent the value using scientific notation		recommended. Instead one can represent the value using
	such a 1.2e3. TODO - Open Issue. Some people would like to		scientific notation such a 1.2e3. The "kg" unit is exception to
	have SI prefixes to improve human readability.		this rule since it is an SI base unit; the "g" unit is provided
			for legacy compatibility.
	5. For a given type of measurement, there will only be one unit		5. For a given type of measurement, there will only be one unit
	type defined. So for length, meters are defined and other		type defined. So for length, meters are defined and other
	lengths such as mile, foot, light year are not allowed. For		lengths such as mile, foot, light year are not allowed. For
	most cases, the SI unit is preferred.		most cases, the SI unit is preferred.
	6. Symbol names that could be easily confused with existing common		6. Symbol names that could be easily confused with existing common
	units or units combined with prefixes should be avoided. For		units or units combined with prefixes should be avoided. For
	example, selecting a unit name of "mph" to indicate something		example, selecting a unit name of "mph" to indicate something
	that had nothing to do with velocity would be a bad choice, as		that had nothing to do with velocity would be a bad choice, as
	skipping to change at page 24, line 17 ¶		skipping to change at page 23, line 45 ¶
	allocated.		allocated.
	10. A number after a unit typically indicates the previous unit		10. A number after a unit typically indicates the previous unit
	raised to that power, and the / indicates that the units that		raised to that power, and the / indicates that the units that
	follow are the reciprocal. A unit should have only one / in the		follow are the reciprocal. A unit should have only one / in the
	name.		name.
	11. A good list of common units can be found in the Unified Code for		11. A good list of common units can be found in the Unified Code for
	Units of Measure [UCUM].		Units of Measure [UCUM].
	12.2. SenML label registry		11.2. SenML label registry
	IANA will create a registry for SenML labels. The initial content of		IANA will create a new registry for SenML labels. The initial
	the registry are shown in TODO.		content of the registry are shown in Table 1 and Table 4.
	New entries can be added to the registration by either Expert Review		New entries can be added to the registration by either Expert Review
	or IESG Approval as defined in [RFC5226]. Experts should exercise		or IESG Approval as defined in [RFC5226]. Experts should exercise
	their own good judgment but need to consider that shorter labels		their own good judgment but need to consider that shorter labels
	should have more strict review.		should have more strict review.
	12.3. Media Type Registration		All new SenML labels that have "base" semantics (see Section 4.1)
			must start with character 'b'. Regular labels must not start with
			that character.
			All new entries must define the Label Name, Label, JSON Type, and XML
			Type.
			11.3. Media Type Registration
	The following registrations are done following the procedure		The following registrations are done following the procedure
	specified in [RFC6838] and [RFC7303].		specified in [RFC6838] and [RFC7303].
	12.3.1. senml+json Media Type Registration		11.3.1. senml+json Media Type Registration
	Type name: application		Type name: application
	Subtype name: senml+json and sensml+json		Subtype name: senml+json and sensml+json
	Required parameters: none		Required parameters: none
	Optional parameters: none		Optional parameters: none
	Encoding considerations: Must be encoded as using a subset of the		Encoding considerations: Must be encoded as using a subset of the
	skipping to change at page 25, line 11 ¶		skipping to change at page 24, line 47 ¶
	outside temperature in a given city, to very private information that		outside temperature in a given city, to very private information that
	requires integrity and confidentiality protection, such as patient		requires integrity and confidentiality protection, such as patient
	health information. This format does not provide any security and		health information. This format does not provide any security and
	instead relies on the transport protocol that carries it to provide		instead relies on the transport protocol that carries it to provide
	security. Given applications need to look at the overall context of		security. Given applications need to look at the overall context of
	how this media type will be used to decide if the security is		how this media type will be used to decide if the security is
	adequate.		adequate.
	Interoperability considerations: Applications should ignore any JSON		Interoperability considerations: Applications should ignore any JSON
	key value pairs that they do not understand. This allows backwards		key value pairs that they do not understand. This allows backwards
	compatibility extensions to this specification. The "ver" field can		compatibility extensions to this specification. The "bver" field can
	be used to ensure the receiver supports a minimal level of		be used to ensure the receiver supports a minimal level of
	functionality needed by the creator of the JSON object.		functionality needed by the creator of the JSON object.
	Published specification: RFC-AAAA		Published specification: RFC-AAAA
	Applications that use this media type: The type is used by systems		Applications that use this media type: The type is used by systems
	that report electrical power usage and environmental information such		that report e.g., electrical power usage and environmental
	as temperature and humidity. It can be used for a wide range of		information such as temperature and humidity. It can be used for a
	sensor reporting systems.		wide range of sensor reporting systems.
	Additional information:		Additional information:
	Magic number(s): none		Magic number(s): none
	File extension(s): senml		File extension(s): senml and sensml
	Macintosh file type code(s): none		Macintosh file type code(s): none
	Person & email address to contact for further information: Cullen		Person & email address to contact for further information: Cullen
	Jennings <fluffy@iii.ca>		Jennings <fluffy@iii.ca>
	Intended usage: COMMON		Intended usage: COMMON
	Restrictions on usage: None		Restrictions on usage: None
	Author: Cullen Jennings <fluffy@iii.ca>		Author: Cullen Jennings <fluffy@iii.ca>
	Change controller: IESG		Change controller: IESG
	12.3.2. senml+cbor Media Type Registration		11.3.2. senml+cbor Media Type Registration
	Type name: application		Type name: application
	Subtype name: senml+cbor		Subtype name: senml+cbor and sensml+cbor
	Required parameters: none		Required parameters: none
	Optional parameters: none		Optional parameters: none
	Encoding considerations: TBD		Encoding considerations: TBD
	Security considerations: TBD
			Security considerations: See Section 11.3.1
	Interoperability considerations: TBD		Interoperability considerations: TBD
	Published specification: RFC-AAAA		Published specification: RFC-AAAA
	Applications that use this media type: The type is used by systems		Applications that use this media type: See Section 11.3.1
	that report electrical power usage and environmental information such
	as temperature and humidity. It can be used for a wide range of
	sensor reporting systems.
	Additional information:		Additional information:
	Magic number(s): none		Magic number(s): none
			File extension(s): senmlc and sensmlc
	File extension(s): senml
	Macintosh file type code(s): none		Macintosh file type code(s): none
	Person & email address to contact for further information: Cullen		Person & email address to contact for further information: Cullen
	Jennings <fluffy@iii.ca>		Jennings <fluffy@iii.ca>
	Intended usage: COMMON		Intended usage: COMMON
	Restrictions on usage: None		Restrictions on usage: None
	Author: Cullen Jennings <fluffy@iii.ca>		Author: Cullen Jennings <fluffy@iii.ca>
	Change controller: IESG		Change controller: IESG
	12.3.3. senml+xml Media Type Registration		11.3.3. senml+xml Media Type Registration
	Type name: application		Type name: application
	Subtype name: senml+xml and sensml+xml		Subtype name: senml+xml and sensml+xml
	Required parameters: none		Required parameters: none
	Optional parameters: none		Optional parameters: none
	Encoding considerations: TBD		Encoding considerations: TBD
	Security considerations: TBD		Security considerations: See Section 11.3.1
	Interoperability considerations: TBD		Interoperability considerations: TBD
	Published specification: RFC-AAAA		Published specification: RFC-AAAA
	Applications that use this media type: TBD
			Applications that use this media type: See Section 11.3.1
	Additional information:		Additional information:
	Magic number(s): none		Magic number(s): none
	File extension(s): senml		File extension(s): senmlx and sensmlx
	Macintosh file type code(s): none		Macintosh file type code(s): none
	Person & email address to contact for further information: Cullen		Person & email address to contact for further information: Cullen
	Jennings <fluffy@iii.ca>		Jennings <fluffy@iii.ca>
	Intended usage: COMMON		Intended usage: COMMON
	Restrictions on usage: None		Restrictions on usage: None
	Author: Cullen Jennings <fluffy@iii.ca>		Author: Cullen Jennings <fluffy@iii.ca>
	Change controller: IESG		Change controller: IESG
	12.3.4. senml-exi Media Type Registration		11.3.4. senml-exi Media Type Registration
	Type name: application		Type name: application
	Subtype name: senml-exi		Subtype name: senml-exi and sensml-exi
	Required parameters: none		Required parameters: none
	Optional parameters: none		Optional parameters: none
	Encoding considerations: TBD		Encoding considerations: TBD
	Security considerations: TBD		Security considerations: TBD
	Interoperability considerations: TBD		Interoperability considerations: TBD
	Published specification: RFC-AAAA		Published specification: RFC-AAAA
	Applications that use this media type: TBD		Applications that use this media type: See Section 11.3.1
	Additional information:		Additional information:
	Magic number(s): none		Magic number(s): none
	File extension(s): senml		File extension(s): senmle and sensmle
	Macintosh file type code(s): none		Macintosh file type code(s): none
	Person & email address to contact for further information: Cullen		Person & email address to contact for further information: Cullen
	Jennings <fluffy@iii.ca>		Jennings <fluffy@iii.ca>
	Intended usage: COMMON		Intended usage: COMMON
	Restrictions on usage: None		Restrictions on usage: None
	Author: Cullen Jennings <fluffy@iii.ca>		Author: Cullen Jennings <fluffy@iii.ca>
	Change controller: IESG		Change controller: IESG
	skipping to change at page 28, line 15 ¶		skipping to change at page 28, line 5 ¶
	Jennings <fluffy@iii.ca>		Jennings <fluffy@iii.ca>
	Intended usage: COMMON		Intended usage: COMMON
	Restrictions on usage: None		Restrictions on usage: None
	Author: Cullen Jennings <fluffy@iii.ca>		Author: Cullen Jennings <fluffy@iii.ca>
	Change controller: IESG		Change controller: IESG
	12.4. XML Namespace Registration		11.4. XML Namespace Registration
	This document registers the following XML namespaces in the IETF XML		This document registers the following XML namespaces in the IETF XML
	registry defined in [RFC3688].		registry defined in [RFC3688].
	URI: urn:ietf:params:xml:ns:senml		URI: urn:ietf:params:xml:ns:senml
	Registrant Contact: The IESG.		Registrant Contact: The IESG.
	XML: N/A, the requested URIs are XML namespaces		XML: N/A, the requested URIs are XML namespaces
	12.5. CoAP Content-Format Registration		11.5. CoAP Content-Format Registration
	IANA is requested to assign CoAP Content-Format IDs for the SenML		IANA is requested to assign CoAP Content-Format IDs for the SenML
	media types in the "CoAP Content-Formats" sub-registry, within the		media types in the "CoAP Content-Formats" sub-registry, within the
	"CoRE Parameters" registry [RFC7252]. All IDs are assigned from the		"CoRE Parameters" registry [RFC7252]. All IDs are assigned from the
	"Expert Review" (0-255) range. The assigned IDs are show in Table 4.		"Expert Review" (0-255) range. The assigned IDs are show in Table 6.
	+-------------------------+-----+		+-------------------------+-----+
	| Media type | ID |		| Media type | ID |
	+-------------------------+-----+		+-------------------------+-----+
	| application/senml+json | TBD |		| application/senml+json | TBD |
	| application/sensml+json | TBD |		| application/sensml+json | TBD |
	| application/senml+cbor | TBD |		| application/senml+cbor | TBD |
	| application/senml+xml | TBD |		| application/senml+xml | TBD |
	| application/sensml+xml | TBD |		| application/sensml+xml | TBD |
	| application/senml-exi | TBD |		| application/senml-exi | TBD |
	+-------------------------+-----+		+-------------------------+-----+
	Table 4: CoAP Content-Format IDs		Table 6: CoAP Content-Format IDs
	13. Security Considerations		12. Security Considerations
	See Section 14. Further discussion of security properties can be		See Section 13. Further discussion of security properties can be
	found in Section 12.3.		found in Section 11.3.
	14. Privacy Considerations		13. Privacy Considerations
	Sensor data can range from information with almost no security		Sensor data can range from information with almost no security
	considerations, such as the current temperature in a given city, to		considerations, such as the current temperature in a given city, to
	highly sensitive medical or location data. This specification		highly sensitive medical or location data. This specification
	provides no security protection for the data but is meant to be used		provides no security protection for the data but is meant to be used
	inside another container or transport protocol such as S/MIME or HTTP		inside another container or transport protocol such as S/MIME or HTTP
	with TLS that can provide integrity, confidentiality, and		with TLS that can provide integrity, confidentiality, and
	authentication information about the source of the data.		authentication information about the source of the data.
	15. Acknowledgement		14. Acknowledgement
	We would like to thank Lisa Dusseault, Joe Hildebrand, Lyndsay		We would like to thank Lisa Dusseault, Joe Hildebrand, Lyndsay
	Campbell, Martin Thomson, John Klensin, Bjoern Hoehrmann, Carsten		Campbell, Martin Thomson, John Klensin, Bjoern Hoehrmann, Carsten
	Bormann, and Christian Amsuess for their review comments.		Bormann, and Christian Amsuess for their review comments.
	The CBOR Representation text and CDDL was contributed by Carsten		15. References
	Bormann.
	16. References
	16.1. Normative References		15.1. Normative References
	[BIPM] Bureau International des Poids et Mesures, "The		[BIPM] Bureau International des Poids et Mesures, "The
	International System of Units (SI)", 8th edition, 2006.		International System of Units (SI)", 8th edition, 2006.
	[IEEE.754.1985]		[IEEE.754.1985]
	Institute of Electrical and Electronics Engineers,		Institute of Electrical and Electronics Engineers,
	"Standard for Binary Floating-Point Arithmetic", IEEE		"Standard for Binary Floating-Point Arithmetic", IEEE
	Standard 754, August 1985.		Standard 754, August 1985.
	[NIST811] Thompson, A. and B. Taylor, "Guide for the Use of the		[NIST811] Thompson, A. and B. Taylor, "Guide for the Use of the
	skipping to change at page 29, line 49 ¶		skipping to change at page 29, line 36 ¶
	[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, DOI 10.17487/		Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/
	RFC2119, March 1997,		RFC2119, March 1997,
	<http://www.rfc-editor.org/info/rfc2119>.		<http://www.rfc-editor.org/info/rfc2119>.
	[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,		[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
	DOI 10.17487/RFC3688, January 2004,		DOI 10.17487/RFC3688, January 2004,
	<http://www.rfc-editor.org/info/rfc3688>.		<http://www.rfc-editor.org/info/rfc3688>.
	[RFC4627] Crockford, D., "The application/json Media Type for
	JavaScript Object Notation (JSON)", RFC 4627, DOI
	10.17487/RFC4627, July 2006,
	<http://www.rfc-editor.org/info/rfc4627>.
	[RFC4648] Josefsson, S., "The Base16, Base32, and Base64 Data		[RFC4648] Josefsson, S., "The Base16, Base32, and Base64 Data
	Encodings", RFC 4648, DOI 10.17487/RFC4648, October 2006,		Encodings", RFC 4648, DOI 10.17487/RFC4648, October 2006,
	<http://www.rfc-editor.org/info/rfc4648>.		<http://www.rfc-editor.org/info/rfc4648>.
	[RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an		[RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an
	IANA Considerations Section in RFCs", BCP 26, RFC 5226,		IANA Considerations Section in RFCs", BCP 26, RFC 5226,
	DOI 10.17487/RFC5226, May 2008,		DOI 10.17487/RFC5226, May 2008,
	<http://www.rfc-editor.org/info/rfc5226>.		<http://www.rfc-editor.org/info/rfc5226>.
	[RFC6838] Freed, N., Klensin, J., and T. Hansen, "Media Type		[RFC6838] Freed, N., Klensin, J., and T. Hansen, "Media Type
	skipping to change at page 30, line 42 ¶		skipping to change at page 30, line 24 ¶
	[RFC7303] Thompson, H. and C. Lilley, "XML Media Types", RFC 7303,		[RFC7303] Thompson, H. and C. Lilley, "XML Media Types", RFC 7303,
	DOI 10.17487/RFC7303, July 2014,		DOI 10.17487/RFC7303, July 2014,
	<http://www.rfc-editor.org/info/rfc7303>.		<http://www.rfc-editor.org/info/rfc7303>.
	[W3C.REC-exi-20110310]		[W3C.REC-exi-20110310]
	Schneider, J. and T. Kamiya, "Efficient XML Interchange		Schneider, J. and T. Kamiya, "Efficient XML Interchange
	(EXI) Format 1.0", World Wide Web Consortium		(EXI) Format 1.0", World Wide Web Consortium
	Recommendation REC-exi-20110310, March 2011,		Recommendation REC-exi-20110310, March 2011,
	<http://www.w3.org/TR/2011/REC-exi-20110310>.		<http://www.w3.org/TR/2011/REC-exi-20110310>.
	16.2. Informative References		15.2. Informative References
	[I-D.arkko-core-dev-urn]		[I-D.arkko-core-dev-urn]
	Arkko, J., Jennings, C., and Z. Shelby, "Uniform Resource		Arkko, J., Jennings, C., and Z. Shelby, "Uniform Resource
	Names for Device Identifiers", draft-arkko-core-dev-urn-03		Names for Device Identifiers", draft-arkko-core-dev-urn-03
	(work in progress), July 2012.		(work in progress), July 2012.
	[I-D.greevenbosch-appsawg-cbor-cddl]		[I-D.greevenbosch-appsawg-cbor-cddl]
	Vigano, C. and H. Birkholz, "CBOR data definition language		Vigano, C. and H. Birkholz, "CBOR data definition language
	(CDDL): a notational convention to express CBOR data		(CDDL): a notational convention to express CBOR data
	structures", draft-greevenbosch-appsawg-cbor-cddl-08 (work		structures", draft-greevenbosch-appsawg-cbor-cddl-08 (work
	in progress), March 2016.		in progress), March 2016.
	[I-D.ietf-core-links-json]		[I-D.ietf-core-links-json]
	Li, K., Rahman, A., and C. Bormann, "Representing CoRE		Li, K., Rahman, A., and D. Bormann, "Representing CoRE
	Formats in JSON and CBOR", draft-ietf-core-links-json-04		Formats in JSON and CBOR", draft-ietf-core-links-json-05
	(work in progress), November 2015.		(work in progress), April 2016.
	[RFC2141] Moats, R., "URN Syntax", RFC 2141, DOI 10.17487/RFC2141,		[RFC2141] Moats, R., "URN Syntax", RFC 2141, DOI 10.17487/RFC2141,
	May 1997, <http://www.rfc-editor.org/info/rfc2141>.		May 1997, <http://www.rfc-editor.org/info/rfc2141>.
	[RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform		[RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
	Resource Identifier (URI): Generic Syntax", STD 66, RFC		Resource Identifier (URI): Generic Syntax", STD 66, RFC
	3986, DOI 10.17487/RFC3986, January 2005,		3986, DOI 10.17487/RFC3986, January 2005,
	<http://www.rfc-editor.org/info/rfc3986>.		<http://www.rfc-editor.org/info/rfc3986>.
	[RFC4122] Leach, P., Mealling, M., and R. Salz, "A Universally		[RFC4122] Leach, P., Mealling, M., and R. Salz, "A Universally
	skipping to change at page 32, line 13 ¶		skipping to change at page 31, line 42 ¶
	and defined by [I-D.ietf-core-links-json].		and defined by [I-D.ietf-core-links-json].
	The link extension can be an array of objects that can be used for		The link extension can be an array of objects that can be used for
	additional information. Each object in the Link array is constrained		additional information. Each object in the Link array is constrained
	to being a map of strings to strings with unique keys.		to being a map of strings to strings with unique keys.
	The following shows an example of the links extension.		The following shows an example of the links extension.
	[{"bn": "urn:dev:ow:10e2073a01080063/",		[{"bn": "urn:dev:ow:10e2073a01080063/",
	"bt": 1320078429,		"bt": 1320078429,
	"l": "[{\"href\":\"humidity\",\"foo\":\"bar1\"}\"		"l": "[{\"href\":\"humidity\",\"foo\":\"bar1\"}",
	},		"n": "temperature", "v": 27.2, "u": "Cel" },
	{ "n": "temperature", "v": 27.2, "u": "Cel" },
	{ "n": "humidity", "v": 80, "u": "%RH" }		{ "n": "humidity", "v": 80, "u": "%RH" }
	]		]
	Authors' Addresses		Authors' Addresses
	Cullen Jennings		Cullen Jennings
	Cisco		Cisco
	400 3rd Avenue SW		400 3rd Avenue SW
	Calgary, AB T2P 4H2		Calgary, AB T2P 4H2
	Canada		Canada
	Phone: +1 408 421-9990		Phone: +1 408 421-9990
	Email: fluffy@cisco.com		Email: fluffy@iii.ca
	Zach Shelby		Zach Shelby
	ARM		ARM
	150 Rose Orchard		150 Rose Orchard
	San Jose 95134		San Jose 95134
	USA		USA
	Phone: +1-408-203-9434		Phone: +1-408-203-9434
	Email: zach.shelby@arm.com		Email: zach.shelby@arm.com
	skipping to change at page 33, line 4 ¶		skipping to change at page 32, line 28 ¶
	Phone: +1-408-203-9434		Phone: +1-408-203-9434
	Email: zach.shelby@arm.com		Email: zach.shelby@arm.com
	Jari Arkko		Jari Arkko
	Ericsson		Ericsson
	Jorvas 02420		Jorvas 02420
	Finland		Finland
	Email: jari.arkko@piuha.net		Email: jari.arkko@piuha.net
	Ari Keranen		Ari Keranen
	Ericsson		Ericsson
	Jorvas 02420		Jorvas 02420
	Finland		Finland
	Email: ari.keranen@ericsson.com		Email: ari.keranen@ericsson.com
			Carsten Bormann
			Universitaet Bremen TZI
			Postfach 330440
			Bremen D-28359
			Germany
			Phone: +49-421-218-63921
			Email: cabo@tzi.org
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