Hints and tips:
...Google’s answer is to ask such owners to go to their router’s settings and change the name of the network (SSID) by adding “ _nomap” to it. So, it would become “MyHomeWiFi_nomap” for example....
...Unfortunately, many people believe that their WiFi network is secured after changing its default public name or “SSID” (Service Set Identifier, Network Name), or disabling SSID broadcasting....
...If you do need to track down an SSID (network name) or password, the set-up guide explains how for most WiFi routers and access points....
...It is also a good idea change the name of the network - the Service Set Identifier or SSID - to your e-mail address, and to check the security settings on a network from time to time....
International Edition