esp-idf/examples/mesh/ip_internal_network

Supported Targets	ESP32	ESP32-C3	ESP32-C6	ESP32-S2	ESP32-S3

Mesh IP Internal Networking example

This example demonstrates how to use mesh to create a IP capable sub-network. As a demonstration all nodes publish their IP and their internal mesh layer to MQTT broker and uses internal communication at the same time

Functionality

This example uses experimental NAT feature to translate addresses/ports from an internal subnet, that is created by the root node running a DHCP server. At the same time, the nodes communicate using low level mesh send/receive API to exchange data, such as routing table from root to all nodes and an event notification from one node to all other nodes in the mesh. As a demonstration, the same event is also published at the mqtt broker on a subscribed topic, so both internal mesh_recv() notification as well as mqtt data event are to be received.

Note, that this example in not supported for IPv6-only configuration.

Hardware Required

This example can be executed on any platform board, the only required interface is WiFi and connection to internet.

Configure the project

Open the project configuration menu (idf.py menuconfig) to configure the mesh network channel, router SSID, router password and mesh softAP settings.

Build and Flash

Build the project and flash it to multiple boards forming a mesh network, then run monitor tool to view serial output:

idf.py -p PORT flash monitor

(To exit the serial monitor, type Ctrl-].)

See the Getting Started Guide for full steps to configure and use ESP-IDF to build projects.

Example Output

Output sample from mesh node

I (7749) mesh_main: <MESH_EVENT_TODS_REACHABLE>state:0
I (7749) mesh_main: <MESH_EVENT_ROOT_ADDRESS>root address:24:0a:c4:09:88:5d
I (7899) wifi:AP's beacon interval = 307200 us, DTIM period = 2
I (8809) mesh_main: <IP_EVENT_STA_GOT_IP>IP:10.0.0.3
I (8819) mesh_main: Tried to publish layer:2 IP:10.0.0.3
I (8819) mesh_mqtt: Other event id:7
I (9189) MQTT_CLIENT: Sending MQTT CONNECT message, type: 1, id: 0000
I (9469) mesh_mqtt: MQTT_EVENT_CONNECTED
I (9569) mesh_mqtt: sent publish returned msg_id=42728
I (9839) mesh_mqtt: MQTT_EVENT_SUBSCRIBED, msg_id=60327
I (9919) mesh_mqtt: MQTT_EVENT_PUBLISHED, msg_id=42728
...
I (1218786) MESH_MQTT: sent publish returned msg_id=13978
W (1218836) mesh_main: Key pressed!
I (1218836) MESH_MQTT: sent publish returned msg_id=15808
I (1218846) mesh_main: Sending to [0] 30:ae:a4:80:5b:18: sent with err code: 0
I (1218906) MESH_MQTT: MQTT_EVENT_PUBLISHED, msg_id=13978
I (1219016) MESH_MQTT: MQTT_EVENT_PUBLISHED, msg_id=15808
I (1219366) MESH_MQTT: MQTT_EVENT_DATA
TOPIC=/topic/ip_mesh/key_pressed
DATA=24:0a:c4:09:88:5c
I (1220036) mesh_main: Received Routing table [0] 30:ae:a4:80:5b:18
I (1220036) mesh_main: Received Routing table [1] 24:0a:c4:09:88:5c

Output sample from the root node

I (11957) mesh_main: <MESH_EVENT_TODS_REACHABLE>state:0
I (11967) mesh_main: <MESH_EVENT_ROOT_ADDRESS>root address:24:0a:c4:09:88:5d
I (11967) wifi:AP's beacon interval = 102400 us, DTIM period = 3
I (12767) esp_netif_handlers: sta ip: 192.168.2.3, mask: 255.255.255.0, gw: 192.168.2.1
I (12767) mesh_main: <IP_EVENT_STA_GOT_IP>IP:192.168.2.3
...
I (1253864) mesh_main: Received Routing table [0] 30:ae:a4:80:5b:18
I (1253864) mesh_main: Received Routing table [1] 24:0a:c4:09:88:5c
I (1253874) mesh_main: Sending routing table to [0] 30:ae:a4:80:5b:18: sent with err code: 0
I (1253884) mesh_main: Sending routing table to [1] 24:0a:c4:09:88:5c: sent with err code: 0
I (1253974) MESH_MQTT: MQTT_EVENT_PUBLISHED, msg_id=18126
W (1254714) mesh_main: Keypressed detected on node: 24:0a:c4:09:88:5c
I (1254814) MESH_MQTT: MQTT_EVENT_DATA
TOPIC=/topic/ip_mesh/key_pressed
DATA=24:0a:c4:09:88:5c