This document provides an overview of OMA LwM2M including: 1. A description of LwM2M and its related standard activities. 2. Details on the LwM2M specification and architectural model including objects, resources, and the client-server communication protocol. 3. A summary of the results of the 2018 OMA LwM2M Test Fest including testing of specifications and multi-vendor interoperability.

1. OMA LwM2M
Architectural model and system specification
briefly
Hamdamboy Urunov, Ph.D. student.
Special Communication Research Center.,
Kookmin University
Seoul, South Korea
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2. Contents
1. LwM2M related standard activity
2. Specification and architectural model
3. TEST FEST 2018 proceeding result
4. Implementation solutions
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3. 1. LwM2M related standard activity (1/)
IETF Applications OMA LwM2M oneM2M ZigBee & WiSUN
Wed, RESTFul
(HTTP, CoAP)
RESTFul/CoAP
(Smart Objects)
Application Entity (AE)
(Tracking, Metering, R
emote)
(HAN & LAN)
Home & Large
Internet resource : https://connect2.io/open-mobile-alliance-lightweightm2m-oma-lwm2m/
• Until recently, there was no industry standard for the remote management of M2M or IoT devices.
• This contrasts with the established industry standards that cater for the remote management
requirements of fixed network broadband DSL routers (TR-69), enterprise IP networks (SNMP) and
mobile phones (OMA DM).
http://www.openmobilealliance.org/wp/OMA Specifications :
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4. 1. LwM2M related standard activity (2/)
Physical Layer OMA LwM2M Client Dedicated Node Devices
IPv6 Protocol
Transport & Security
(OMA Web Objects) (ADN)
Sensors / Actuators
ZigBee
WiSUN
Communication Network Networks Services Network
Connectivity &
Security
Interworking
(Cellular Capacity)
Device Triggering, QoS Sec.
(NSE)
Sub-GHz.
802.15.4g/e
IETF Processing OMA LwM2M Server Common Services Large Area
Data Centers
(Servers, Cloud)
Device Management Data & Device Management
(Directory, Server, Security) (CSE)
6LoWPAN
Stack
IETF Applications OMA LwM2M oneM2M ZigBee & WiSUN
Wed, RESTFul
(HTTP, CoAP)
RESTFul/CoAP
(Smart Objects)
Application Entity (AE) (HAN & LAN)
(Tracking, Metering, Remote) Home & Large
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5. 2. Specification and architectural model (1/)
• OMA LWM2M is a good fit for ‘Over-The-Air’ (OTA) management of IoT wireless sensor platforms because it utili
zes a simpler protocol and COAP over UDP with a very small overhead (10s of bytes) and the device client is a l
ot smaller.
LWM2M Architecture
• Bootstrap
• Device Discovery and Registration
• Device Management and Service Enablemen
t
• Information Reporting
OMA LWM2M defines the application layer communicatio
n protocol between a server and a client.
Four logical interfaces are defined between server an
d client namely:
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6. 2. Specification and architectural model (2/)
LWM2M Architecture 6

7. What are OBJECTS and RESOURCES ?!
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8. 2. Specification and architectural model (3/)
OBJECTS and RESOURCES with real implementation solutions
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9. 2. Specification and architectural model (4/)
• The LWM2M Client resides on the device and is typically integrated as a software library or a built-in functi
on of a module or device.
• The LWM2M standard defines provisioning and bootstrapping fu
nctionality that allows a LWM2M Bootstrap Server to manage the
keying, access control and configuration of a device to enroll
with a LWM2M Server.
BOOTSTRAPPING
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10. 2. Specification and architectural model (5/)
• CoAP messages are encoded in a simple binary format, allowing this functionality starting with just a 4-byte overhead.
LWM2M defines the UDP Binding with CoAP as mandatory whereas the SMS Binding with CoAP is optional.
CoAP
• coaps://leshan.eclipse.org:5683
• Port number: 5683
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11. 2. Specification and architectural model (6/)
• LWM2M includes security to secure communications between client and server using Datagram Transport
Layer Security (DTLS). DTLS is used to provide a secure channel between the LWM2M Server and the LWM2
M Client for all the messages interchanged.
Security model and DTLS
• coaps://leshan.eclipse.org:5684
• Port number: 5684
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12. 2. Specification and architectural model (7/)
• Resource is defined to have one or more operations that it supports.
• A Resource MAY consist of multiple instances called a Resource Instance as defined in the Object specification
• The LWM2M Server can send “Write” operation with JSON or TLV format to Resource to instantiate a Resource Instance.
• The LWM2M Client also has the capability to instantiate a Resource Instance..
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13. Test Fests 2018
July, Seoul
https://www.omaspecworks.org/events/testfests/event/v4xr/ 13

14. 3. TEST FEST 2018 proceeding result (1/)
OMA TestFests are designed to achieve a number of goals, including:
• Ensuring the quality of OMA SpecWorks specifications
• Enabling vendors to verify and test the interoperability of their product implementations in a multi-vendor
environment
• Provide a peer-to-peer networking environment for participants
TestFests
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15. 3. TEST FEST 2018 proceeding result (2/)
1. Ensuring the quality of OMA SpecWorks specifications
Internet source : http://openmobilealliance.org/release/LightweightM2M/V1_1-20180612-C/OMA-TS-LightweightM2M_Transport-V1_1-20180612-C.pdf 15

16. 3. TEST FEST 2018 proceeding result (3/)
Internet source : http://openmobilealliance.org/release/LightweightM2M/V1_1-20180612-C/OMA-TS-LightweightM2M_Transport-V1_1-20180612-C.pdf
The Protocol Stack of the LwM2M Enabler
• This specification defines the transport bindings for the LwM2M messaging protocol used between
LwM2M Clients, LwM2M Bootstrap Servers and LwM2M Servers
• In particular, this specification defines the following transport bindings: CoAP over UDP CoAP over DTLS
(over UDP) CoAP over SMS CoAP over DTLS over SMS CoAP over TCP CoAP over TLS (over TCP)
CoAP over Non-IP (includes 3GPP CIoT and LoRaWAN)
More details (see Page 11)
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17. 3. TEST FEST 2018 proceeding result (4/)
Internet source : http://openmobilealliance.org/release/LightweightM2M/V1_1-20180612-C/OMA-TS-LightweightM2M_Transport-V1_1-20180612-C.pdf
More details (see Page 34)
Bootstrap Interface
Example of Client initiated Bootstrap exchange
• The client bootstrap operation is performed by sending a
CoAP POST request to the LwM2M Bootstrap-Server at
the "/bs" path including the Endpoint Client Name as a
query string parameter.
• When the bootstrap operation is terminated the Bootstrap
-Server MUST send a Bootstrap-Finish indication.
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18. 3. TEST FEST 2018 proceeding result (5/)
https://github.com/eclipse/leshanEclipse Leshan™ is an OMA Lightweight M2M server and client Java implementation.
Enabling vendors to verify and test the interoperability of their product implementations in a multi-
vendor environment
Product implementations
server client
CoAP, etc.
Open source
Your source code
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19. 3. TEST FEST 2018 proceeding result (6/)
https://github.com/eclipse/leshan
Test Server Sandbox
Basically start to installing process
•The lwm2m server at https://leshan.eclipse.org/
(coap://leshan.eclipse.org:5683 and coaps://leshan.eclipse.org:5684)
• The bootstrap server at https://leshan.eclipse.org/bs/
(coap://leshan.eclipse.org:5783 and coaps://leshan.eclipse.org:5784)
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20. 3. TEST FEST 2018 proceeding result (7/)
https://github.com/eclipse/leshan
(Automatic deployment of master branch)
Result of client connection to server
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21. 3. TEST FEST 2018 proceeding result (8/)
https://github.com/eclipse/leshan
Test Leshan Demos locally
Get and run the last binary of our demo server :
wget https://hudson.eclipse.org/leshan/job/leshan/lastSuccessfulBuild/artifact/leshan-server-demo.jar java -jar ./leshan-server-demo.jar
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22. Implementation
• LWM2M FOTA and Data Demonstration System
https://ltd-docs.readthedocs.io/en/osf-17.10/iotfoundry/lwm2m-howto.html
• The system contains Zephyr-based IoT devices, an IoT
gateway, and a web application, Leshan, that is used as
the LWM2M server.
• With Leshan you can issue commands, query data and
perform firmware over the air (FOTA) updates on the
IoT device(s).
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23. Firmware over the air (FOTA)
Continue…
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24. Thank You
hamdamboy.urunov@gmail.com