mbed-os/features/net/FEATURE_IPV6/mbed-mesh-api

mbed mesh API

ARM mbed mesh API allows the client to use the IPv6 mesh network.

The client can use the LoWPANNDInterface or ThreadInterface object for connecting to the mesh network and when successfully connected, the client can create a socket by using the mbed C++ socket API to start communication with a remote peer.

Supported mesh networking modes

Currently, 6LoWPAN-ND (neighbour discovery) and Thread bootstrap modes are supported.

Module Configuration

This module supports static configuration via mbed configuration system by using the mbed_app.json file. The application needs to create the configuration file if it wants to use other than default settings.

An example of the configuration file:

{
    "target_overrides": {
        "*": {
            "target.features_add": ["IPV6"],
            "mbed-mesh-api.6lowpan-nd-channel": 12,
            "mbed-mesh-api.6lowpan-nd-channel-mask": "(1<<12)",
            "mbed-mesh-api.heap-size": 10000
        }
    }
}

Configurable parameters in section mbed-mesh-api:

Parameter name	Value	Description
heap-size	number [0-0xfffe]	Nanostack's internal heap size

Thread related configuration parameters:

Parameter name	Value	Description
thread-pskd	string [6-255 chars]	Human-scaled commissioning credentials.
hread-device-type	enum from mesh_device_type_t	Set device operating mode.
thread-config-channel-mask	number [0-0x07fff800]	Channel mask, 0x07fff800 scans all channels.
thread-config-channel-page	number [0, 2]	Channel page, 0 for 2,4 GHz and 2 for sub-GHz radios.
thread-config-channel	number [0-27]	RF channel to use.
thread-config-panid	number [0-0xFFFF]	Network identifier.
thread-master-key	byte array [16]	Network master key.
thread-config-ml-prefix	byte array [8]	Mesh local prefix.
thread-config-pskc	byte array [16]	Pre-Shared Key for the Commissioner.

6LoWPAN related configuration parameters:

Parameter name	Type	Description
6lowpan-nd-channel-mask	number [0-0x07fff800]	Channel mask, bit-mask of channels to use
6lowpan-nd-channel-page	number [0, 2]	0 for 2,4 GHz and 2 for sub-GHz radios
6lowpan-nd-channel	number [0-27]	RF channel to use when channel_mask is not defined
6lowpan-nd-security-mode	"NONE" or "PSK"	To use either no security, or Pre shared network key
6lowpan-nd-psk-key-id	number	PSK key id when PSK is enabled
6lowpan-nd-psk-key	byte array [16]	Pre shared network key
6lowpan-nd-sec-level	number [1-7]	Network security level. Use default 5

Usage notes

This module should not be used directly by the applications. The applications should use the LoWPANNDInterface or ThreadInterface directly.

Network connection states

After the initialization, the network state is MESH_DISCONNECTED. After a successful connection, the state changes to MESH_CONNECTED and when disconnected from the network the state is changed back to MESH_DISCONNECTED.

In case of connection errors, the state is changed to some of the connection error states. In an error state, there is no need to make a disconnect request and the client is allowed to attempt connecting again.

Getting started

See the example application mbed-os-example-mesh-minimal for usage.

Usage example for 6LoWPAN ND mode

Create a network interface:

LoWPANNDInterface mesh;

Connect:

    if (mesh.connect()) {
        printf("Connection failed!\r\n");
        return -1;
    }

    printf("connected. IP = %s\r\n", mesh.get_ip_address());

Usage example for 6LoWPAN Thread mode

Basically the same as for ND, but the network interface uses different class:

ThreadInterface mesh;
mesh.connect();