Thanks for your quick reply, i had established the communication now. Basically both are configured as routers so they cant be able to communicate with each other. Later on i configured them one as router AT and other as coordinator AT by updating the firmware, now its working fine i can able to send data and receive it. But i have few more doubts like how can i establish a mesh network, how to route the data from on router AT to other, and how can i send data in API mode etc. Please guide me.