Hi,

you can broadcast a message with Rime stack. There are examples in the repository https://github.com/contiki-os/contiki/tree/master/examples/rime

Or you can use publisher/subscriber model with MQTT protocol (http://mqtt.org/) . In this case, a broker like mosquitto need to be installed and available in the network. In the device side, use mqtt client library for publishing/subscribing message. One example is http://hacks.esar.org.uk/contiki-mqtt-client/ One advantage using mqtt is you will be able to broadcast a message to a variety of clients (no need to be a 'contiki device').

Thank You for the answer

Hi I Putu Susila,

I just want to know whether contiki can be real-time. do you have an idea regarding this case?

thank you