Definition of Captive Portal
A webpage which is permitted to be viewed and accessed by a public-network user before the authenticated access is granted will be called a captive portal. These are generally utilized by business centers or entities where frequent and massive public interference is a regular norm such as airports, cafes, and hotel lobbies, etc. Wherever Wi-Fi hotspots are available for internet users, captive portals are activated.
Understanding a Wi-Fi Hotspot
Any area where wireless internet access is available will be termed as a Wi-Fi hotspot. The term Hotspot is interchangeably used for the place where the wi-fi signals are available and the device that broadcast the signals. This device can be a Wi-Fi router or a Wi-Fi access point (WAP). Similarly, Wi-Fi Router and WAP/Wireless Access Point are two terms that are interchangeably used.
Captive Portals and Hotspots
Almost all the commercially activated Hotspots are actually Captive Portals. The hotspots appear as areas offering unencrypted or open Wi-Fi signal and once users have logged on, these redirect the traffic to a particular web page. This web page is known as the “Splash Page” and usually it asks users about login information or informs them about the fees of internet access. The beneficial aspect is that a majority of the laptops get automatically connected to the Open wi-fi signal. As soon as the client runs Internet Explorer or any other browser, they are instantly directed to the Splash page regardless of the website they are trying to access.
What are DIY Captive Portals?
If a user doesn’t want to utilize a hosted Hotspot the other option available is the DIY Captive Portal. DIY Captive Portals are those commercial software packages that act as actual captive portals and usually run on Linux or Windows OS. The requirement is that a DIY portal has to be activated on a PC 24 hours a day.
How Captive Portals Function?
Once a user firstly logs on to a network where captive portal is enabled, the user will encounter a web page that asks him/her to perform certain actions before allowing full fledge internet access. These actions may include going through an Acceptable Use Policy or AUP and clicking on the button for accepting the terms and conditions. Some captive portals can ask the user for a pre-assigned ID and password while some just display sponsored advertisement which the user must close in order to access the internet.
Benefits of Captive Portals
Captive portals are mainly used for authenticating the users and limiting their access. The use of captive portals is beneficial because the authentication process not just discourages but minimizes the use of hotspots as platforms for carrying out illegal activities. Usually, all the servers where captive portals have been enabled comprise of anti-virus and firewall programs, which also offer comprehensive security to users and their data.
Another beneficial aspect is that captive portals minimize bandwidth hogging through a technique called bandwidth shaping or bandwidth throttling. This can be performed by conducting additional programming in the settings of captive portal. Bandwidth shaping can limit the speed at which users download large files as well as the size of files that are allowed to be downloaded. The controlling program limits the number of files a user can download in a single session and can also restrict access of such sites where large files are usually available for downloading such as torrents.