CMi6160
User’s Manual English
CMi6160
User’s Manual English
page | 11 (38)
[2022-10]
v1.4
6 Integration guide
6.1 Purpose
This chapter provides the technical details needed to integrate an Elvaco NB-IoT module with a MDM
and/or DM server.
Note that this section will provide device-specific information and is meant to be used with the
common “Elvaco NB-IoT MCM Integrator’s guide”.
6.2 Introduction
For device management, the module will act as a LWM2M device connecting to a LwM2M server. The
Device Management system enables configuration and monitoring of a CMi6160 module remotely. This
includes setting configuration parameters, update the firmware and trigger momentaneous/historical
readouts of the module. For meter data transport, the module uses the MQTT-SN protocol.
Upon activation, the device will attempt to connect to its configured bootstrap server via the mobile (NB-
IoT) network. When successful, the module will receive connection credentials, i.e. IP addresses to the
DM server and the meter data server.
The module will thereafter connect to the DM server and perform a DTLS handshake to generate the
session key used to encrypt the data that is transmitted between DM server and module. Note that using
DTLS is optional, and the product also support unencrypted communication.
The module will thereafter connect to the MQTT-SN gateway and perform a DTLS handshake to
generate the sessions keys used to encrypt the meter data transport.
Each module has a security chip where a device-unique set of keys are stored. These are provisioned to
the module during production. The UDP transport of both DM and MDM can be secured using DTLS 1.2.
Either the pre-provisioned keys can be used, or new keys can be provisioned during the bootstrap phase.
6.3
Status and configuration parameters
Table 1 below provides a list of all CMi6160 status and configuration parameters accessible on LwM2M.
Op.
LwM2M object
LwM2M resource
ID
Type
Range or
Enumeration
Comment
R
LwM2M Security
LWM2M Server
URI
0/0/0
String
Bootstrap URI
R
LwM2M Security
Bootstrap server
0/0/1
Bool
TRUE
R
LwM2M Security
Security Mode
0/0/2
Integer
0..4
BS Security
mode
0 = PSK mode
3 = No security
R
LwM2M Security
PSK Identity
0/0/3
Opaque
DevEUI
-
LwM2M Security
Secret Key
0/0/4
Opaque
Bootstrap PSK
R
LwM2M Security
Short Server ID
0/0/10
Integer
1..65534
R
LwM2M Server
Short Server ID
1/0/0
Integer
1..65534
R
LwM2M Server
Lifetime
1/0/1
Integer
E
LwM2M Server
Bootstrap-
Request Trigger
1/0/9
R(W)
LwM2M Security
LWM2M Server
URI
0/1/0
String
DM ServerURI
Writable by
Bootstrap server
R
LwM2M Security
Bootstrap server
0/1/1
Bool
FALSE
