Keep Your WiFi Signal to Yourself

I have been using Smartbro Fixed Wireless Broadband for more than two years. But right now, there's an ongoing renovation at home. I am forced to use the wireless USB which is a prepaid connection. I think I end up paying more because I stay online a lot. An unlimited subscription is a better choice for me.

I am currently looking into my options. Is WiFi connection good? I learned that there are paints that can block WiFi signals so that you can confine the signals within the corners of your house. Does this work like emi shielding? I am still learning how the thing works. Based on my research, the paint is fairly cheap. It contains aluminum oxide that can block both incoming and outgoing wifi signals.