Book excerpt: This book was first published in 2015. Since then, the Wi-Fi technology has evolved tremendously. This 2020 edition has important updates about security. Once hackers take control of your Wi-Fi router, they can attack connected devices such as phones, laptops, computers! Fortunately, it is easy to harden the defense of your home network. There are important steps you should take in order to protect your connected devices. An exhaustive catalog of the latest home security devices has been updated in this 2020 edition. Why would you spend a lot of money to have a home security system installed when you can do it yourself! A chapter about health risks has also been added. Are EMF radiations safe? We regularly post updates on our site http://mediastimulus.com such as security alerts and the latest in Wi-Fi technology. Your feedback is always welcome http://mediastimulus.com/contact/