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Versions: 00

CoRE                                                P. van der Stok, Ed.
Internet-Draft                                                consultant
Intended status: Standards Track                              J. Jimenez
Expires: April 30, 2017                                         Ericsson
                                                        October 27, 2016


              Mapping from LWM2M model to CoMI YANG model
                  draft-vanderstok-core-yang-lwm2m-00

Abstract

   This document defines a set of rules to convert a LWM2M xml-based
   device specification to a YANG MODULE.  The invocation of the server
   executing the converted YANG code makes use of CoMI.  The mapping
   from the original LWM2M URI to the corresponding CoMI URI is
   presented.

Note

   Discussion and suggestions for improvement are requested, and should
   be sent to roll@ietf.org.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at http://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on April 30, 2017.

Copyright Notice

   Copyright (c) 2016 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of



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   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
     1.1.  Terminology . . . . . . . . . . . . . . . . . . . . . . .   3
       1.1.1.  Tree Diagrams . . . . . . . . . . . . . . . . . . . .   3
   2.  Conversion rules LWM2M to YANG  . . . . . . . . . . . . . . .   4
   3.  URI convention  . . . . . . . . . . . . . . . . . . . . . . .   7
   4.  observation and notification  . . . . . . . . . . . . . . . .   8
   5.  Payload format  . . . . . . . . . . . . . . . . . . . . . . .   8
   6.  YANG extensions to LWM2M  . . . . . . . . . . . . . . . . . .   8
   7.  Security considerations . . . . . . . . . . . . . . . . . . .   8
   8.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .   8
   9.  Changelog . . . . . . . . . . . . . . . . . . . . . . . . . .   8
   10. References  . . . . . . . . . . . . . . . . . . . . . . . . .   9
     10.1.  Normative References . . . . . . . . . . . . . . . . . .   9
     10.2.  Informative References . . . . . . . . . . . . . . . . .   9
   Appendix A.  YANG identifiers as IDnumbers  . . . . . . . . . . .  10
   Appendix B.  YANG identifiers as resource names . . . . . . . . .  13
   Appendix C.  YANG identifiers as additional leaf  . . . . . . . .  16
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  21

1.  Introduction

   Standardization organizations define interfaces hosted by processors
   to manipulate the connected equipment.  Examples of such
   standardization organizations are BACnet, KNX, ZigBee, oBIX, OMA/
   IPSO, and many others.  These organizations plan to move to resource
   based interfaces.  The data models proposed by these organizations
   are hierarchical models that can be specified in XML and describe
   classes with attributes and operations that can be instantiated to
   objects.  An example is the OMA LWM2M (see [OMNA]) Object model, that
   standardizes eight numbered object types for device management.  IPSO
   (see [IPSO]) expands those objects to handle applications.  This
   document describes rules to translate xml specifications of the
   LWM2M/IPSO organizations to YANG [RFC7950], and the invocation of the
   YANG based server according to the CoAP Management Interface (CoMI)
   specification [I-D.vanderstok-core-comi].







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1.1.  Terminology

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in [RFC2119].

   The following terms are defined in [RFC6241] and are not redefined
   here:

   o  client

   o  configuration data

   o  server

   o  state data

   The following terms are defined in [RFC7950] and are not redefined
   here:

   o  data model

   o  data node

   The terminology for describing YANG data models is found in
   [RFC7950].

1.1.1.  Tree Diagrams

   A simplified graphical representation of the data model is used in
   the YANG modules specified in this document.  The meaning of the
   symbols in these diagrams is as follows:

      Brackets "[" and "]" enclose list keys.

      Abbreviations before data node names: "rw" means configuration
      data (read-write) and "ro" state data (read-only).

      Symbols after data node names: "?" means an optional node, "!"
      means a presence container, and "*" denotes a list and leaf-list.

      Parentheses enclose choice and case nodes, and case nodes are also
      marked with a colon (":").

      Ellipsis ("...") stands for contents of subtrees that are not
      shown.





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2.  Conversion rules LWM2M to YANG

   LWM2M objects are typed, where each type is identified with a number.
   The object provides one or more instances which are numbered.  An
   instance is composed of resources, also identified with numbers.  An
   instance on a host can be accessed with the example URI:
   coap+lwm2m://example.com/object/instance/resource, where resource,
   instance and object are numbers, specified by the LWM2M
   specification.

   When using YANG, the object identifiers, followed by the resource
   identifier, are YANG strings instead of numbers.  The format of the
   instance identifier depends on the YANG model that is chosen to
   specify LWM2M objects.

   For an automatic translation from the XML LWM2M specification to a
   YANG specification, the following rules apply for access, optional,
   units, and range specifications:

   o  The optional/mandatory aspect of the LWM2M resource is covered by
      the leaf's mandatory "false/true" statement of YANG as specified
      in section 7.6.5 of [RFC7950].  The YANG statement "mandatory =
      TRUE" means that(given the right conditions) the leaf must exist.

   o  The R,W access aspects of a data item are translated using the
      YANG "config" statement as specified in section 7.21.1 of
      [RFC7950].  If "config" is "true", the Data nodes are part of
      configuration datastores, resulting in RW access.  If "config" is
      "false", the data nodes are not part of configuration datastores,
      resulting in R access.  YANG does not provide facilities to
      specify W access only.

   o  When the YANG RPC is specified, E access is meant.  In section
      7.14 of [RFC7950] RPCs are modelled for NETCONF using YANG input
      and output parameters.  When input parameters are added, EW access
      is meant; when output parameters are added, ER access is meant and
      with both input and output parameters ERW access is meant.

   o  The YANG ACTION is specified in section 7.15 of [RFC7950].
      Contrary to RPC, ACTION statement is associated with a data node.
      The data node has E access.  Input leafs of the data node have W
      access, and output leafs have R access.

   o  To specify the range of a data resource the YANG range statement,
      specified in section 9.2.4 of [RFC7950], is used.

   o  YANG range can be used in a straightforward fashion for items of
      type integer.  The range of decimal64, used for float, is less



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      straightforward.  The possible ranges are restricted by the
      fraction-digits which specifies the size of the fraction part of
      the float (see section 9.3.4. of [RFC7950].

   o  The YANG units statement, specified in section 7.3.3 of [RFC7950],
      is used to express the units.

   o  The attributes of the YANG leaf need to be presented in the order:
      "type", possibly qualified with "range", "units", "config",
      "mandatory", and finally "Description".

   o  In the presented YANG specification the LWM2M resources are
      specified as leafs of a YANG list.

   YANG lists may contain key leafs which uniquely identify an instance
   in a list.  By specifying a key leaf (for example called "instance")
   that contains the list instance number, the YANG list instance can be
   uniquely referenced by the instance number.  Accordingly, OMA objects
   are modelled as YANG lists.  The value of the "instance" leaf in the
   list is equal to the instance number of the OMA object.  The
   numbering of the instances does not need to be consecutive.  The OMA
   resources are the other leafs of the YANG list.

   Choices need to be made how to represent the numbered object ID, and
   resource ID as YANG identifiers.  YANG identifiers are strings and
   cannot be represented by numbers.

   The YANG identifier strings need to be mapped to numbered
   identifiers.  The appendices show 3 ways to represent the LWM2M
   device ID and resource ID in the YANG specification.

   o  In Appendix A, Yang Identifiers are modelled as strings that start
      with string "ID" followed by the identifier number (see module
      humidityID).

   o  In Appendix B, Yang Identifiers of objects and resources are
      modelled as strings that are equivalent to the OMA object- and
      resource- name (see module humidityNM).

   o  In Appendix C, the OMA device is modelled as a YANG container
      composed of an identifier and a list of instances.  The list is
      composed of an instance number and a set of resource containers.
      The resource container is composed of the pair (attribute
      identifier number, IPSO resource specification)(see module
      humidityLF).

   Below the tree diagrams (see Section 1.1.1 for an explanation of the
   syntax) of the three valid YANG modules are shown.



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   module: ietf-yang-humidityID
   +--ro ID3304* [instance]
   +--ro instance                            uint16
   +--ro ID5700                              decimal64
   +--ro ID5701?                             string
   +--ro ID5601?                             decimal64
   +--ro ID5602?                             decimal64
   +--ro ID5603?                             decimal64
   +--ro ID5604?                             decimal64
   +---x ID5605


   module: ietf-yang-humidityNM
   +--ro IPSO-humidity* [instance]
   +--ro instance                             uint16
   +--ro Sensor_Value                         decimal64
   +--ro Units?                               string
   +--ro Min_Measured_Value?                  decimal64
   +--ro Max_Measured_Value?                  decimal64
   +--ro Min_Range_Value?                     decimal64
   +--ro Max_Range_Value?                     decimal64
   +---x Reset_Min_and_Max_measured_values

   module: ietf-yang-humidityLF
   +--rw IPSO-humidity
   +--ro identifier    uint16
   +--ro resources* [instance]
   +--ro instance                             uint16
   +--ro Sensor_Value
   |  +--ro identifier?                       uint16
   |  +--ro content                           decimal64
   +--ro Units
   |  +--ro identifier?                       uint16
   |  +--ro content?                          string
   +--ro Min_Measured_Value
   |  +--ro identifier?                       uint16
   |  +--ro content?                          decimal64
   +--ro Max_Measured_Value
   |  +--ro identifier?                       uint16
   |  +--ro content?                          decimal64
   +--ro Min_Range_Value
   |  +--ro identifier?                       uint16
   |  +--ro content?                          decimal64
   +--ro Max_Range_Value
   |  +--ro identifier?                       uint16
   |  +--ro content?                          decimal64
   +--ro Reset_Min_and_Max_measured_values
   +--ro identifier?                          uint16



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   +---x reset


   Module humidityLF of Appendix C is the most complex one and is not
   recommended.  Module humidityID of Appendix A works but is a bit
   forced approach and lacks the resource name.  Module humidityNM of
   Appendix B is the most natural approach where the YANG identifiers
   are equal to the device (type) and resource names.

   CoMI [I-D.vanderstok-core-comi] uses a conversion from names to
   numbers to reduce the request URI size, and the payload of the server
   requests and answers.  The LWM2M organization specifies both the
   names and the numbers of the devices and resources.  The number of
   the resource is not unique and for the CoMI identifier the resource
   number needs to be prefixed by the device number to be unique.

3.  URI convention

   The invocation URI of a LWM2M resource looks like:

   coap+lwm2M://example.com/object/instance/resource

   In this section it is assumed that the YANG mapping of the module
   humidityNM of Appendix B is used.

   When YANG is used, the LWM2M resource invocation can follow the
   RESTCONF convention using http, or the CoMI convention using CoAP.

   When using RESTCONF (see section 3.5.3 of [I-D.ietf-netconf-restconf]
   the invocation of object with instance = number will look like:

   http://example.com/object/instance=number/resource

   In the case of CoMI the object/resource numbers are used, and not the
   names, to reduce the payload size.  The instance is specified in a
   query parameter.  Consequently, the LWM2M resource on a server
   executing a YANG specification, is accessed according to the CoMI
   specification with:

   coap://example.com/identifier?k=number

   The identifier is a composition of the object number and the resource
   number.  Assume that n is smallest number for which
   10**(n+1)/resource >= 1.  The value of the identifier =
   (object*10**n)+resource.

   Assume that the IPSO-humidity/Sensor_Value 3304/5700 numbers are
   composed to the numeric identifier 33045700.  According to [RFC4648],



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   the identifier is represented in base64 which leads to B-DzE.  The
   URI for the CoMI invocation of instance 0 of IPSO-humidity/
   Sensor_value will look like:

   coap://example.com/B-DzE?k=0

   For LWM2M objects with only one instance, the k=0 can be omitted.

4.  observation and notification

   An LWM2M server uses "observe" to receive notification from the
   server.  This remains unchanged with YANG servers and CoMI.

5.  Payload format

   The payload of the request and the response follows the payload
   format specified for CoMI.  The content format is CBOR [RFC7049].
   The YANG objects are returned as maps containing (identifier, value)
   pairs.  Where the identifier is the numeric identifier discussed in
   Section 3. and the value is of the type specified by the YANG
   specification of the server.  The CBOR encoding of the YANG types is
   specified in [I-D.ietf-core-yang-cbor].

6.  YANG extensions to LWM2M

   By adding keys leafs to a list object, YANG allows additionally the
   selection of instances by the contents of the key leafs.

   The FETCH method of CoAP makes it possible to request multiple
   resource instances in one request.

   The notification statement of YANG encourages a more flexible
   specification of notifications.

7.  Security considerations

   To be filled in

8.  Acknowledgements

   We are grateful to

9.  Changelog

   NO changes from nothing to version 00






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10.  References

10.1.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <http://www.rfc-editor.org/info/rfc2119>.

   [RFC7950]  Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
              RFC 7950, DOI 10.17487/RFC7950, August 2016,
              <http://www.rfc-editor.org/info/rfc7950>.

   [RFC6241]  Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
              and A. Bierman, Ed., "Network Configuration Protocol
              (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011,
              <http://www.rfc-editor.org/info/rfc6241>.

   [RFC4648]  Josefsson, S., "The Base16, Base32, and Base64 Data
              Encodings", RFC 4648, DOI 10.17487/RFC4648, October 2006,
              <http://www.rfc-editor.org/info/rfc4648>.

   [RFC7049]  Bormann, C. and P. Hoffman, "Concise Binary Object
              Representation (CBOR)", RFC 7049, DOI 10.17487/RFC7049,
              October 2013, <http://www.rfc-editor.org/info/rfc7049>.

   [I-D.vanderstok-core-comi]
              Stok, P. and A. Bierman, "CoAP Management Interface",
              draft-vanderstok-core-comi-09 (work in progress), March
              2016.

   [I-D.ietf-core-yang-cbor]
              Veillette, M., Pelov, A., Somaraju, A., Turner, R., and A.
              Minaburo, "CBOR Encoding of Data Modeled with YANG",
              draft-ietf-core-yang-cbor-02 (work in progress), July
              2016.

10.2.  Informative References

   [I-D.ietf-netconf-restconf]
              Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
              Protocol", draft-ietf-netconf-restconf-17 (work in
              progress), September 2016.

   [OMNA]     "Open Mobile Naming Authority (OMNA)", Web
              http://http://technical.openmobilealliance.org/Technical/
              technical-information/omna.




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   [IPSO]     "IP for Smart Objects (IPSO)",
              Web http://ipso-alliance.github.io/pub/.

Appendix A.  YANG identifiers as IDnumbers

   Yang Identifiers are modelled as string that starts with ID followed
   by the identifier number.  The device object is modelled as a list
   that contains multiple instances.

   <CODE BEGINS> file "ietf-humidityID@2016-07-25.yang"
           module ietf-humidityID{

           yang-version 1.1;  // needed for action

           namespace
           "urn:ietf:params:xml:ns:yang:ietf-humidityID";

           prefix humid;

           organization
           "IPSO";

           contact
           "WG Web:   http://tools.ietf.org/wg/core/
           WG List:  mailto:core@ietf.org

           WG Chair: Carsten Bormann
           mailto:cabo@tzi.org

           WG Chair: Jaime Jimenez
           mailto:jaime.jimenez@ericsson.com

           Editor:   Peter van der Stok
           mailto:consultancy@vanderstok.org

           Editor:   Jaime Jimenez
           mailto:jaime.jimenez@ericsson.com";

           description
   "This module contains information about the operation of the
   IPSO LWM2M humidity sensor with ID 3304.

   Copyright (c) 2016 IETF Trust and the persons identified as
   authors of the code.  All rights reserved.

   Redistribution and use in source and binary forms, with or
   without modification, is permitted pursuant to, and subject
   to the license terms contained in, the Simplified BSD License



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   set forth in Section 4.c of the IETF Trust's Legal Provisions
   Relating to IETF Documents
           (http://trustee.ietf.org/license-info).

   This version of this YANG module is part of RFC XXXX; see
   the RFC itself for full legal notices.";

           revision "2016-07-25" {
           description "Initial revision.";
           reference
   "I-D:draft-vanderstok-core-yang-lwm2m: YANG language applied
   to the LWM2M IPSO humidity sensor specification";
           }

           list ID3304 {
           key instance;
           config  false;     // should be same for key leaf
           description
           "IPSO humidity: The humidity sensor is composed of
            a set of instances";
           leaf instance {
           type uint16{
           range "0..1";   // only one instance zero (0)
           }
           config false;    // R access
           mandatory "true";
           description
           "the number of the humidity sensor instance";
           }
           leaf ID5700 {
           type decimal64{    // YANG has no float
           fraction-digits 2;
           range "10.0 .. 66.6";}
           config false;    // R access
           mandatory "true";
           description
           "Sensor Value: Last or Current Measured Value
              from the Sensor";
           }
           leaf ID5701 {
           type string;
           units "Defined by 'Units' resource";
           config false;    // R access
           description
           "Units: Measurement unit definition
               e.g. 'Cel' for temperature in Celsius";
           }
           leaf ID5601 {



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           type decimal64{    // YANG has no float
           fraction-digits 2;
           range "10.0 .. 66.6";}
           units "Defined by 'Units' resource";
           config false;   // R access
           description
           "Min Measured Value: The minimum value measured
             by the sensor since power ON or reset";
           }
           leaf ID5602 {
           type decimal64{    // YANG has no float
           fraction-digits 2;
           range "10.0 .. 66.6";}
           units "Defined by 'Units' resource";
           config false;    // R access
           description
           "Max Measured Value: The maximum value measured
              by the sensor since power ON or reset";
           }
           leaf ID5603 {
           type decimal64{    // YANG has no float
           fraction-digits 2;
           range "10.0 .. 66.6";}
           units "Defined by 'Units' resource";
           config false;    // R access
           description
           "Min Range Value: The minimum value that
              can be measured by the sensor";
           }
           leaf ID5604 {
           type decimal64{    // YANG has no float
           fraction-digits 2;
           range "10.0 .. 66.6";}
           units "Defined by 'Units' resource";
           config false;    // R access
           description
           "Max Range Value: The maximum value that
              can be measured by the sensor";
           }
           action ID5605 {
           //E access: this is an RPC
           //    without input and output parameters
           description
           "Reset Min and Max measured values: Reset the
              Min and Max measured values to current value";
           }
           }  // list ID3304
           } // module ietf-yang-humidity



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           <CODE ENDS>


Appendix B.  YANG identifiers as resource names

   Yang Identifiers are modelled as strings that represent the resource
   name.  The device object is modelled as a list with multiple
   instances.

   <CODE BEGINS> file "ietf-humidityNM@2016-07-25.yang"

   module ietf-humidityNM{

   yang-version 1.1;  // needed for action

   namespace
               "urn:ietf:params:xml:ns:yang:ietf-humidityNM";

   prefix humid;

               organization
               "IPSO";

               contact
               "WG Web:   http://tools.ietf.org/wg/core/
               WG List:  mailto:core@ietf.org

               WG Chair: Carsten Bormann
               mailto:cabo@tzi.org

               WG Chair: Jaime Jimenez
               mailto:jaime.jimenez@ericsson.com

               Editor:   Peter van der Stok
               mailto:consultancy@vanderstok.org

               Editor:   Jaime Jimenez
               mailto:jaime.jimenez@ericsson.com";

               description
     "This module contains information about the
   operation of the IPSO LWM2M humidity sensor with ID 3304.

   Copyright (c) 2016 IETF Trust and the persons identified as
   authors of the code.  All rights reserved.

   Redistribution and use in source and binary forms, with or
   without modification, is permitted pursuant to, and subject



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   to the license terms contained in, the Simplified BSD License
   set forth in Section 4.c of the IETF Trust's Legal Provisions
   Relating to IETF Documents
         (http://trustee.ietf.org/license-info).

   This version of this YANG module is part of RFC XXXX; see
   the RFC itself for full legal notices.";

               revision "2016-07-25" {
               description "Initial revision.";
               reference
               "I-D:draft-vanderstok-core-yang-lwm2m:
   YANG language applied to the LWM2M IPSO humidity sensor
   specification";
               }


               list IPSO-humidity {
               key instance;
               config   false;   //  should be same as key leaf
               description
               "3304: The humidity sensor is composed of
                 a set of instances";
               leaf instance {
               type uint16{
               range "0..1";   // only one instance zero (0)
               }
               config false;    // R access
               mandatory "true";
               description
               "the number of the humidity sensor instance";
               }
               leaf Sensor_Value  {
               type decimal64{    // YANG has no float
               fraction-digits 2;
               range "10.0 .. 66.6";}
               units "Defined by 'Units' resource";
               config false;    // R access
               mandatory "true";
               description
               "5700: Last or Current Measured Value
                  from the Sensor";
               }
               leaf Units {
               type string;
               units "Defined by 'Units' resource";
               config false;    // R access
               description



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               "5701: Measurement unit definition
                   e.g. 'Cel' for temperature in Celsius";
               }
               leaf Min_Measured_Value {
               type decimal64{    // YANG has no float
               fraction-digits 2;
               range "10.0 .. 66.6";}
               units "Defined by 'Units' resource";
               config false;    // R access
               description
               "5601: The minimum value measured by
                  the sensor since power ON or reset";
               }
               leaf Max_Measured_Value {
               type decimal64{    // YANG has no float
               fraction-digits 2;
               range "10.0 .. 66.6";}
               units "Defined by 'Units' resource";
               config false;    // R access
               description
               "5602: The maximum value measured
                   by the sensor since power ON or reset";
               }
               leaf Min_Range_Value {
               type decimal64{    // YANG has no float
               fraction-digits 2;
               range "10.0 .. 66.6";}
               units "Defined by 'Units' resource";
               config false;    // R access
               description
               "5603: The minimum value that can be measured
                  by the sensor";
               }
               leaf Max_Range_Value{
               type decimal64{    // YANG has no float
               fraction-digits 2;
               range "10.0 .. 66.6";}
               units "Defined by 'Units' resource";
               config false;    // R access
               description
               "5604: The maximum value that can be measured
                  by the sensor";
               }
               action Reset_Min_and_Max_measured_values {
               // E access: this is an RPC
               // without input and output parameter
               description
               "5605: Reset the Min and Max measured values



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                  to current value";
               }  // rpc
               }  // list ID3304
               } // module ietf-yang-humidity

               <CODE ENDS>




Appendix C.  YANG identifiers as additional leaf

   The device object is modelled as a container composed of an
   identifier and a list of instances.  The list instance is composed of
   an instance number and a set of resource containers.  The resource
   container is composed of the pair (attribute identifier number, IPSO
   resource specification).


    <CODE BEGINS> file "ietf-humidityLF@2016-07-25.yang"

    module ietf-humidityLF{

    yang-version 1.1;  // needed for rpc

    namespace
      "urn:ietf:params:xml:ns:yang:ietf-humidityLF";

    prefix humid;

                   organization
                   "IPSO";

                   contact
                   "WG Web:   http://tools.ietf.org/wg/core/
                   WG List:  mailto:core@ietf.org

                   WG Chair: Carsten Bormann
                   mailto:cabo@tzi.org

                   WG Chair: Jaime Jimenez
                   mailto:jaime.jimenez@ericsson.com

                   Editor:   Peter van der Stok
                   mailto:consultancy@vanderstok.org

                   Editor:   Jaime Jimenez
                   mailto:jaime.jimenez@ericsson.com";



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                   description
                   "This module contains information about the
   operation of the IPSO LWM2M humidity sensor with ID 3304.

   Copyright (c) 2016 IETF Trust and the persons identified as
   authors of the code.  All rights reserved.

   Redistribution and use in source and binary forms, with or
   without modification, is permitted pursuant to, and subject
   to the license terms contained in, the Simplified BSD License
   set forth in Section 4.c of the IETF Trust's Legal Provisions
   Relating to IETF Documents
   (http://trustee.ietf.org/license-info).

   This version of this YANG module is part of RFC XXXX;
   see the RFC itself for full legal notices.";

                   revision "2016-07-25" {
                   description "Initial revision.";
                   reference
                   "I-D:draft-vanderstok-core-yang-lwm2m:
   YANG language applied to the LWM2M IPSO humidity sensor
   specification";
                   }

                   container IPSO-humidity{
                   description
                   "Device separated in identifier and list";
                   leaf identifier{
                   type uint16;  // fixed to 3304
                   config false;
                   mandatory "true";
                   description
                   "the LWM2M identification number of the device";
                   }
                   list resources {
                   key instance;
                   config  false;   // should be same as key leaf
                   description
                   "3304: The humidity sensor is composed of
                      a set of instances";
                   leaf instance {
                   type uint16{
                   range "0..1";   // only one instance zero (0)
                   }
                   config false;    // R access
                   mandatory "true";
                   description



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                   "the number of the humidity sensor instance";
                   }  // instance number
                   container Sensor_Value  {
                   description
                   "Resource separated in identifier and content";
                   leaf identifier{
                   type uint16;   // fixed to 5700
                   config false;  // R access
                   description
                   "identifier should contain the value 5700";
                   }
                   leaf content{
                   type decimal64{    // YANG has no float
                   fraction-digits 2;
                   range "10.0 .. 66.6";}
                   units "Defined by 'Units' resource";
                   config false;    // R access
                   mandatory "true";
                   description
                   "5700: Last or Current Measured Value
                     from the Sensor";
                   }  // content
                   }  // container
                   container Units {
                   description
                   "Resource separated in identifier and content";
                   leaf identifier{
                   type uint16;   // fixed to 5701
                   config false;  // R access
                   description
                   "identifier should contain the value 5701";
                   }
                   leaf content{
                   type string;
                   units "Defined by 'Units' resource";
                   config false;    // R access
                   description
                   "5701: Measurement unit definition
                     e.g. 'Cel' for temperature in Celsius";
                   }  // content
                   }  // container
                   container Min_Measured_Value {
                   description
                   "Resource separated in identifier and content";
                   leaf identifier{
                   type uint16;   // fixed to 5601
                   config false;  // R access
                   description



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                   "identifier should contain the value 5601";
                   }  // identifier
                   leaf content{
                   type decimal64{    // YANG has no float
                   fraction-digits 2;
                   range "10.0 .. 66.6";}
                   units "Defined by 'Units' resource";
                   config false;    // R access
                   description
                   "5601: The minimum value measured by the
                     sensor since power ON or reset";
                   }  // content
                   }
                   container Max_Measured_Value {
                   description
                   "Resource separated in identifier and content";
                   leaf identifier{
                   type uint16;   // fixed to 5602
                   config false;  // R access
                   description
                   "identifier should contain the value 5602";
                   }
                   leaf content{
                   type decimal64{    // YANG has no float
                   fraction-digits 2;
                   range "10.0 .. 66.6";}
                   units "Defined by 'Units' resource";
                   config false;    // R access
                   description
                   "5602: The maximum value measured by
                     the sensor since power ON or reset";
                   }  // content
                   }  // container
                   container Min_Range_Value {
                   description
                   "Resource separated in identifier and content";
                   leaf identifier{
                   type uint16;   // fixed to 5603
                   config false;  // R access
                   description
                   "identifier should contain the value 5603";
                   }  // identifier
                   leaf content{
                   type decimal64{    // YANG has no float
                   fraction-digits 2;
                   range "10.0 .. 66.6";}
                   units "Defined by 'Units' resource";
                   config false;    // R access



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                   description
                   "5603: The minimum value that can be measured
                      by the sensor";
                   }  // content
                   }  // container
                   container Max_Range_Value{
                   description
                   "Resource separated in identifier and content";
                   leaf identifier{
                   type uint16;   // fixed to 5604
                   config false;  // R access
                   description
                   "identifier should contain the value 5604";
                   }  // identifier
                   leaf content{
                   type decimal64{    // YANG has no float
                   fraction-digits 2;
                   range "10.0 .. 66.6";}
                   units "Defined by 'Units' resource";
                   config false;    // R access
                   description
                   "5604: The maximum value that can be measured
                     by the sensor";
                   }  // content
                   }
                   container Reset_Min_and_Max_measured_values {
                   description
                   "Resource separated in identifier and action";
                   leaf identifier{
                   type uint16;   // fixed to 5605
                   config false;  // R access
                   description
                   "identifier should contain the value 5605";
                   }
                   action reset{
   // E access: this is an RPC without input and output parameters
                   description
                   "5605: Reset the Min and Max measured values to
                    current value";
                   } // action  reset
                   } // container Reset_min_and_max
                   }  // list resources
                   }  // container IPSO-humidity (3304)
                   } // module ietf-yang-humidity

                   <CODE ENDS>





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Authors' Addresses

   Peter van der Stok (editor)
   consultant

   Phone: +31-492474673 (Netherlands), +33-966015248 (France)
   Email: consultancy@vanderstok.org
   URI:   www.vanderstok.org


   Jaime Jimenez
   Ericsson
   Hirsalantie 11
   Jorvas  02420
   Finland

   Phone: +358-442992827(Finland)
   Email: jaime.jimenez@ericsson.com

































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