I am new in MQTT. After watching your video i am able to create a mqtt connect, Publish and Subscribe packet. But, after a short of time my device automatically unsubscribe. So, when i read mqtt 3.1.1 document. Document is telling that i have to send a ping packet to the server before completion of keep alive time period. Can you please help me how can i create a ping packet.
There is documentation of ping packet also its just two bytes i think, Check the Oasis documentation.