Can you send the screen shot of that login page and where do you set security of that network to open.

But i think that i should do reverse engineering with the router firmware,if TP-Link doesn't change in their Legacy Device firmware. I don't know if that is legal or not.

Thanks you for understanding me this much and for appreciating me.

Thanks for replying

I just need one answer that is is there is any way by which i can modify the TP-Link firmware.

If the device in the Internet Cafe is capable of sending and receiving packets 1 KM away then you will be able to connect with the Internet Cafe with your WA7510N. Which device does you internet cafe...