A mobile hotspot is an ad hoc wireless access point that is created by a dedicated hardware device or a smartphone feature that shares the phone's cellular data. Other nearby devices can then use the shared hotspot to connect to the internet.
Mobile hotspots are also known as portable hotspots. The hardware devices used to create them, officially known as pocket or travel routers, are sometimes referred to as mobile hotspots as well. They are also often generically known as Mi-Fis, although that name is owned by Novatel in the United States and many other countries.
Pocket routers access cellular signals and convert 3G and 4G signals to Wi-Fi and vice versa, creating mobile Wi-Fi networks that can be shared by multiple users within about 10 meters of the device. Most wireless carriers offer mobile hotspot devices and the wireless data plans required to enable them. Another option is using a smartphone to connect other devices. Many smartphones enable the creation of a mobile hotspot through tethering, accessing the phone's existing cellular data connection.
The bring-your-own network (BYON) often involves employees creating mobile hotspots at work, which can impact network security. For example, an employee who creates a mobile hotspot at work is simultaneously connected to three networks at once: the cellular carrier's, the hotspot and the corporate network. If the device or any of the networks are not secure, that can put corporate data at risk.