This presentation is delivered by Hannes Tschofening, ARM and Co-chair of IETF ACE & OAuth WGs. IETF has developed a Constrained Application Protocol (CoAP) which is designed to easily translate to HTTP for simplified integration with the web. It is intended for use in resource constrained internet devices. OMA LwM2M uses CoAP as a transport mechanism. In this presentation, our speaker from IETF will provide you with an introduction to CoAP: ● What is CoAP ● How CoAP works ● What other IETF standards are used by LwM2M ● What is next for IETF in this space

1. IETF BUILDING BLOCKS IN THE LWM2M ECOSYSTEM
Hannes Tschofenig
ARM
The information in this presentation is public. | Copyright © 2017 Open Mobile Alliance
LwM2M Workshop, 15th May 2017, Santa Clara

2. IETF
 www.ietf.org -- SDO
developing the core Internet
protocols
 From network layer (IP) to
application layer (HTTP)
 Work happens in groups,
which are clustered into
areas.
 Each group has a mailing list.
 Open participation model:
RFCs, drafts, and email
discussions are public for
everyone.
The information in this presentation is public. | Copyright © 2013 Open Mobile Alliance Ltd. All rights reserved.

3. DESIGN PRINCIPLES
 In “Architectural Principles of the Internet” (RFC 1958) the IAB
describes a number of design principles and, among them, is
modularity.
 In RFC 7452 “Architectural Considerations in Smart Object
Networking” the IAB argued that there is not a single IoT
architecture but different design patterns and suggest to re-use
existing Internet protocols, to take the existing Internet deployment
into account and to design for change.
 Considering extensibility early in the design is important, as
highlighted in RFC 6709 “Design Considerations for Protocol
Extensions”.
Did we took any of into account?

4. LWM2M V1.0 LAYERED ARCHITECTURE
LwM2M
Objects
CoAP
DTLS
UDP
IP
UDPSMS DTLS
SMS IP
Building
Blocks
(designed
to be used
in different
environments)
Complete
Framework

5. MAIN BUILDING BLOCKS
FOR LWM2M V1.0
CoAP DTLS Object Model
The information in this presentation is public. | Copyright © 2013 Open Mobile Alliance Ltd. All rights reserved.

6. COAP & EXTENSIONS
 Semantic of a RESTful
protocol (with methods,
response codes, options,
security, and URI schemes
defined like HTTP)
 Reliable transmission
optional.
 Basic congestion control
algorithm.
 Allows for group
communication using
multicast.
The information in this presentation is public. | Copyright © 2013 Open Mobile Alliance Ltd. All rights reserved.
 Helps with transmission of larger
payloads, such as firmware images.
 Useful to avoid IP fragmentation and for
payloads larger than 64KB.
CoAP
 Observe mechanism to avoid
repeated polling.
 Feature for reducing the notification
rate.
Block-wise Transfer
Observe

7. WHY RE-USE?
 Less work and faster time-to-market
 Code
 Technical specifications
 Utilize the larger expertise, and research investments
 Benefit from familiarity with the concepts
The information in this presentation is public. | Copyright © 2013 Open Mobile Alliance Ltd. All rights reserved.

8. DOES RE-USE WORK?
 Performance tests for computationally demanding functionality done (such as
crypto).
 Early investigations with crypto on microcontrollers have been fed into EEMBC IoT-
Secure benchmarking efforts.
 Optimizations sometimes possible and useful.
 Example: CoAP developed at a time when alternative was HTTP/1.1
 Most of the time profiling is sufficient, see RFC 7925 “DTLS/TLS Profiles for the
Internet of Things”
 Optimizations for IoT environment may be feed back into wider Internet as
well.
 Example: Reduction of roundtrips and improved performance of TLS/DTLS 1.3
The information in this presentation is public. | Copyright © 2013 Open Mobile Alliance Ltd. All rights reserved.

9. PROTOCOL STACK LWM2M V1.1
(SPECULATION*)
Adding
Alternative
Transports
LwM2M
Objects
CoAP
DTLS 1.2
UDP
IP
LPWAN
(e.g. NB-IoT)
Non-IP
TLS 1.2
HTTP/2
TCP
IP
MQTT
(*): No decision about the
features of LwM2M v1.1
have been made.

10. LWM2M V2.0?
(WILD SPECULATION)
Latest developments:
 TLS 1.3 about to be
finalized.
 DTLS 1.3 chartered item for
the TLS working group.
 QUIC as a new transport
protocol aiming to replace
TCP.
LwM2M
Objects
HTTP/2’
QUIC/
TLS 1.3
UDP
IP
DTLS 1.3
LPWAN
(e.g. NB-IoT)
IP
CoAP
Non-IP

11. LWM2M: HOW TO PARTICIPATE?
 I want to contribute to the technical specification
 Submit new objects definitions to the OMA operated repository.
 File issues with the public OMA LWM2M Github issue tracker.
 Become OMA member and participate in the standardization process.
 Participate in the IETF for working on building blocks
 I want to write code
 Several open source projects are happy to receive your contributions.
 Examples: ARM mbed, Leshan / Wakaama, AVSystems, …
 I want to test my implementation
 Join an interoperability test event (PlugFest, TestFest). Info about
upcoming events can be found at the OMA testfest website.
 Use available open source implementations to test against.
 I want to do research
 Help improve IoT security by analysing the security of LwM2M as a whole
or its building blocks.

12. Thank You
The information in this presentation is public. | Copyright © 2017 Open Mobile Alliance

13. MORE INFORMATION?
The information in this presentation is public. | Copyright © 2013 Open Mobile Alliance Ltd. All rights reserved.
OMA LwM2M
version 1.0
specification
Whitepaper
about device
management
Webinar about
LwM2M protocol