Wifi hotspot

A hotspot is a site that offers Internet access over a wireless local area network (WLAN) through the use of a router connected to a link to an Internet service provider. Hotspots typically use Wi-Fi technology.
The public can use a laptop or other suitable portable device to access the wireless connection provided.
For venues that have broadband Internet access, offering wireless access is as simple as configuring one access point (AP), in conjunction with a router and connecting the AP to the Internet connection. A single wireless router combining these functions may suffice.

Diagram showing wifi network

^Security 

Security is a serious concern in connection with Hotspots. 
There are three possible attack vectors. 

• First, there is the wireless connection between the client and the access point. This needs to be encrypted, so that the connection cannot be eavesdropped or attacked by a man-in-the-middle-attack. 
• Second, there is the Hotspot itself. The WLAN encryption ends at the interface, then travels its network stack unencrypted and then travels over the wired connection up to the BRAS of the ISP. 
• Third, there is the connection from the Access Point to the BRAS (Broadband Remote Access Service) of the ISP (Internet Service Provider).

The safest method when accessing the Internet over an Hotspot, with unknown security measures, is end-to-end encryption. Examples of strong end-to-end encryption are HTTPS and SSH (Secure shell).

Types

 Free hotspot operates in following ways:

• Using an open public network is the easiest way to create a free HotSpot. All that is needed is a Wi-Fi router.
• Closed public networks use a HotSpot Management System to control the HotSpot. This software runs on the router itself. With this software, operators can authorize only specific users to access the Internet.

Hotspots are found at restaurants, train stations, airports, libraries, hotels, hospitals, coffee shops, bookstores, fuel stations, department stores, supermarkets, parks, public pay phones, and other public places. Many universities and schools have wireless networks in their campus.