LwM2M Device Simulator

This is a LwM2M device simulator who emulate 4 actions from a Thingy:91 running with nRF Asset Tracker v2 firmware; bootstrapping, connection, sequential updates and heartbeat.

Action	Description	LwM2M Interface	LwM2M Operation	Triggered By
Bootstrapping	Used to provision essential information into the LwM2M Client to enable it to perform the "Register" operation. The Factory Bootstrap is the default mode used	Bootstrap	Factory Bootstrap	LwM2M Client
Connection	Register the device with a LwM2M server and send the value of the object registered. This action mix 3 operation from 2 different interfaces
--		Client Registration	Register	LwM2M Client
--		Dev Mang & Serv Enab	Discover	LwM2M Server
--		Dev Mang & Serv Enab	Read	LwM2M Server
Sequential Updates	Update the value of an object, instance or resource without explicit request of the LwM2M Server	Information Reporting	Send	LwM2M Client
Heartbeat	Extend the lifetime of a registration	Client Registration	Update	LwM2M Client

The main propose of this project is to facilitate the testing process of LwM2M Asset Tracker.

Specifications

This device uses LwM2M as a protocol and provides a command line interface for its interaction. This interface offer 7 different commands and here is one table with the operations from the LwM2M protocol implemented by each command.

Command	Action Emulated	LwM2M Operation	LwM2M Interface	Content Format
clear
register	Connection
--		Client registration	Register	Link Format
--		Discover	Dev Mang & Serv Enab	LwM2M JSON
--		Read	Dev Mang & Serv Enab	LwM2M JSON
list
set	Sequential Update	Send	Information Reporting	SenML JSON
quit
help
heartbeat	Heartbeat	Update	Client Registration	Link Format

CLI reference

command required-param [optional param]

Options:

	List

		List values

	Format: list /[object-id]/[instance-id]/[resource-id]
	Example:
           list
           list /3
           list /3/0
           list /3/0/0
-------------------------------------------------

	Set

		Set resource value

	Format: set object-id/instance-id/resource-id  value
	Example: set /3/0/0 Nordic
-------------------------------------------------

	Register

		Execute LwM2M Client Registration interface

	Format: register
	Example: register
-------------------------------------------------

	Clear

		Clear console

	Format: clear
	Example: clear
-------------------------------------------------

	Quit

		Exit the client

	Format: quit
	Example: quit
-------------------------------------------------

	Help

		List all possible commands

	Format: help
	Example: help
-------------------------------------------------

Installation

npm install

Enviroment variables

Create a .env file in the root of the proyect with the following keys

deviceName=
port=
host=
lifetime=
lwm2mV=
biding=

Where

• deviceName should be the name of the device
• port should be the port of the LwM2M server. 5683, for example.
• host should be the hostname. eu.iot.avsystem.cloud, for example.
• lifetime should be the lifetime desire for the connection between the client and the server. It should be in seconds, 3600 for example.
• lwm2mV should be the LwM2M version used by the client. 1.1, for example.
• biding should be the type of binding that the client supports for communication with the server. U for example, which stands for UDP.

Test

npm test

Execution

npx tsx src/index.ts

Usage

see example to see the usage of the CLI and the expected behavior in each command.

Also you can type help in the CLI in order to get more info about commands.

Limitations

Security Mode

The device simulator does not support credentials or pre-shared keys, and the only security mode option implemented is the No-Sec, which uses the port 5683 for the comunication with the server. The implemented security mode is not recommended for production enviroments.