5G Non IP Data Delivery and Lightweight M2M (LwM2M) over NIDD

Earlier this year, MediaTek had announced that its MT2625 NB-IoT chip has been validated for LwM2M over NIDD on SoftBank Corp.’s cellular network across Japan. This achievement marks the first global commercial readiness of LwM2M over NIDD; a secure, ultra-efficient IoT communications technique that is being adopted by operators worldwide. The benefits of LwM2M over NIDD include security improvements, cost-efficient scalability and reduced power consumption.

LwM2M over NIDD is a combination of the communication technology "NIDD (Non-IP Data Delivery)" that does not use an IP address in LTE communication NB-IoT for IoT and the device management protocol "LwM2M (Lightweight M2M)" advocated by the Open Mobile Alliance. It's been a while since I wrote about Open Mobile Alliance on this blog. OMA SpecWorks is the successor brand to the Open Mobile Alliance. You can read all about it here.

OMA SpecWorks’ LightweightM2M is a device management protocol designed for sensor networks and the demands of a machine-to-machine (M2M) environment. With LwM2M, OMA  SpecWorks has responded to demand in the market for a common standard for managing lightweight and low power devices on a variety of networks necessary to realize the potential of IoT. The LwM2M protocol, designed for remote management of M2M devices and related service enablement, features a modern architectural design based on REST, defines an extensible resource and data model and builds on an efficient secure data transfer standard called the Constrained Application Protocol (CoAP). LwM2M has been specified by a group of industry experts at the OMA SpecWorks Device Management Working Group and is based on protocol and security standards from the IETF.

You can get all the LwM2M resources here and the basic specs of 'Lightweight M2M 1.1: Managing Non-IP Devices in Cellular IoT Networks' here.

The 5G Americas whitepaper 'Wireless Technology Evolution Towards 5G: 3GPP Release 13 to Release 15 and Beyond' details how Current Architecture for 3GPP Systems for IOT Service Provision and Connectivity to External Application Servers. It also talks about Rel-13 Cellular IoT EPS Optimizations which provide improved support of small data transfer over control plane and user plane. Control Plane CIoT EPS Optimization transports user data (measurements, ID, status, etc.) via MME by encapsulating user data in NAS PDUs and reduces the total number of control plane messages when handling a short data transaction. Control Plane CIoT EPS optimization, designed for small infrequent data packets, can also be used for larger data bursts depending in UE Radio capability.

User data transported using the Control Plane CIoT EPS Optimization, has special characteristics, as different mobility anchor and termination nodes.

Therefore, the Preferred Network Behavior signaling must include information on:

• Whether Control Plane CIoT EPS optimization is supported
• Whether User Plane CIoT EPS optimization is supported
• Whether Control Plane CIoT EPS optimization is preferred or whether User Plane CIoT EPS optimization is preferred

These optimizations have enabled:

• Non-IP Data Delivery (NIDD) for both: mobile originated and mobile terminated communications, by using SCEF (Service Capability Exposure Function) or SGi tunneling. However, it has to be taken into account that Non-IP PDUs may be lost and its sequence is not guaranteed
• For IP data, the UE and MME may perform header compression based on Robust Header Compression (ROHC) framework
• NB-IoT UE can attach but not activate any PDN connection
• High latency communication handled by the buffering of downlink data (in the Serving GW or the MME)
• SMS transfer
• EPS Attach, TA Update and EPS Detach procedures for NB-IoT only UEs, with SMS service request
• Procedures for connection suspend and resume are added
• Support for transfer of user plane data without the need for using the Service Request procedure to establish Access Stratum context in the serving eNodeB and UE

When selecting an MME for a UE that is using the NB-IoT RAT, and/or for a UE that signals support for CIoT EPS Optimizations in RRC signaling, the eNodeB’s MME selection algorithm shall select an MME taking into account its Release 13 NAS signaling protocol.

Mpirical has a nice short video explaining 5G Non IP Data Delivery. It is embedded below.

IoT has not taken off as expected and prophesised for years. While the OMASpecWorks is doing some fantastic work by defining simplified approach for IoT deployment, its current member list doesn't have enough operators to drive the uptake required for its spec adoption. They would argue that it doesn't matter how many members there are as the NIDD approach is completely optional and over-the-top. Let's wait and see how it progresses.

Related Posts:

• 3G4G: 5G Service Based Architecture (SBA)
• The 3G4G Blog: Mobile Initiated Connection Only (MICO) mode in 5G System
• The 3G4G Blog: Embedded SIM (eSIM) and Integrated SIM (iSIM)
• The 3G4G Blog: 5G and Industry 4.0
• 3G4G: Internet of Things (IoT) and Machine-2-Machine (M2M)
• The 3G4G Blog: M2M vs IoT
• The 3G4G Blog: What is Industrial IoT (IIoT) and how is it different from IoT?
• The 3G4G Blog: New 3GPP Release-17 Study Item on NR-Lite (a.k.a. NR-Light)