Pocket Wi-fi hotspot is actually a portable pocket hub. It attaches to a mobile phone network via a data-only sim memory card, similar to exactly how your smart devices link to the mobile phone connection. After the Pocket WIFI hub gets the mobile network, it changes the sign and also broadcasts the frequency wave to let cordless devices attach to the WiFi. https://www.yahoo.com/now/muama-ryoko-reviews-4g-wifi-023600605.html