Yes, you can read about ideas at https://www.google.com/search?q=1+kilometer+WiFi but these are never sure or reliable. As to security you use the WPA2 that we have today and change the key every week or when you see unexpected traffic or connections.
This also might cause your ISP to cut you off since most have you agree not to share with neighbors. You have to know this ahead of time so you don't get a surprise disconnection.
Hey all. Apologize if this topic has been discussed around here.
Anyway, I plan to get high speed internet at home and share it to other house about 1km away.
I need a router at home that is also acting as access point for users at home. And it will also communicate with the router at the other house where the router will also serve as access point for users there.
Is this possible? If so, what kind of routers do I need. Of course, it needs to have a good security against unwanted access to the signal.
Thank you in advance.

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