@shiva-shankar About topic 1: The join status reflects the state of message key establishment. Once that has happened, the device is considered as joined. For ABP, joining not even requires a communication between the node and the server. About topic 1 and 2: The communication between node and server via gateway is considered as unreliable. If required, you may request confirmation of uplink messages. if that is returned, you know that the uplink arrived at the TTN server. But TTN reserves the right to restrict the number of downlink messages including confirmation messages. They talk about 10 messages/day. About topic 3. In an open environment, 3-5 km should be possible, given that you have a good and high positioned antenna at the gateway. Yuu may reduced the data rate to get better coverage. In my tests the message from my node were received by gateways up to 8 km away in an area with not too many buildings. These gateways have good outdoor antennas, like the Taoglas Barracuda one, and these were placed outside on the roof of a building. With my own gateway, using a simple ground plane antenna, I reached up to 2.5 km.