emqx/apps/emqx_gateway_lwm2m

emqx_lwm2m

LwM2M (Lightweight Machine-to-Machine) is a protocol designed for IoT devices and machine-to-machine communication. It is a lightweight protocol that supports devices with limited processing power and memory.

The LwM2M Gateway in EMQX can accept LwM2M clients and translate their events and messages into MQTT Publish messages.

In the current implementation, it has the following limitations:

• Based UDP/DTLS transport.
• Only supports v1.0.2. The v1.1.x and v1.2.x is not supported yet.
• Not included LwM2M Bootstrap services.

Quick Start

In EMQX 5.0, LwM2M gateway can be configured and enabled through the Dashboard.

It can also be enabled via the HTTP API, and emqx.conf e.g, In emqx.conf:

gateway.lwm2m {
  xml_dir = "etc/lwm2m_xml/"
  auto_observe = true
  enable_stats = true
  idle_timeout = "30s"
  lifetime_max = "86400s"
  lifetime_min = "1s"
  mountpoint = "lwm2m/${endpoint_namea}/"
  qmode_time_window = "22s"
  update_msg_publish_condition = "contains_object_list"
  translators {
    command {qos = 0, topic = "dn/#"}
    notify {qos = 0, topic = "up/notify"}
    register {qos = 0, topic = "up/resp"}
    response {qos = 0, topic = "up/resp"}
    update {qos = 0, topic = "up/update"}
  }
  listeners {
    udp {
      default {
        bind = "5783"
        max_conn_rate = 1000
        max_connections = 1024000
      }
    }
  }
}

Note: Configuring the gateway via emqx.conf requires changes on a per-node basis, but configuring it via Dashboard or the HTTP API will take effect across the cluster.

Object definations

emqx_lwm2m needs object definitions to parse data from lwm2m devices. Object definitions are declared by organizations in XML format, you could find those XMLs from LwM2MRegistry, download and put them into the directory specified by lwm2m.xml_dir. If no associated object definition is found, response from device will be discarded and report an error message in log.

More documentations: LwM2M Gateway