Captive Portal: 

A Captive Portal is a web page that is displayed to users when they first connect to a Wi-Fi network or a specific network access point, before they are granted full access to the internet or other network resources. Captive portals are commonly used in public places such as cafes, airports, hotels, and universities, where users are required to interact with the portal before accessing the network. 

How Does a Captive Portal Work: 

  • Connection: When a user connects to a Wi-Fi network, they are initially unable to access the internet or any other network resources. 
  • Redirect: The network device (usually a router or access point) automatically redirects the user’s web browser to the captive portal page, even if they try to visit a website. 
  • Interaction: The user is presented with a login page, terms and conditions, or other instructions, depending on the configuration. 
  • Access: Once the user authenticates or accepts the terms, the portal grants them access to the network, and they can begin browsing the internet or using the network.  

 

Types of Captive Portal: 

1. Click to Login 

  • Description: This is the simplest form of authentication. Users are redirected to the captive portal page, where they can click a button or link to gain access to the network. 
  • How It Works: When users connect to the network, the captive portal page opens automatically, and they just click on a button (usually labeled "Login" or "Accept") to proceed. 
  • Example: A user connects to the Wi-Fi in a coffee shop and clicks a "Login" button to access the network. 

2. Voucher 

  • Description: A voucher-based system requires users to enter a unique code (voucher) to access the network. 
  • How It Works: Users are given a voucher code, which may be provided through a printed card, email, or SMS. The voucher code is entered into the captive portal to authenticate access. 
  • Example: A hotel provides guests with a voucher code to access Wi-Fi during their stay. 

3. Survey 

  • Description: In this method, users must complete a survey or questionnaire before they are granted access to the network. 
  • How It Works: The captive portal displays a survey (usually related to the business or service offering the network), and users must fill it out (e.g., answer a few questions or provide feedback) to proceed to the network. 
  • Example: A customer at a shopping mall fills out a short survey on the captive portal page to get free Wi-Fi. 

4. Username & Password 

  • Description: Users are required to enter a username and password to authenticate and access the network. 
  • How It Works: The user is prompted to enter credentials (usually set up by the network provider or organization) into the captive portal. Upon correct authentication, they are granted network access. 
  • Example: A university provides students with a username and password to log in to the campus Wi-Fi network. 

5. OTP via Email 

  • Description: One-Time Password (OTP) is sent to the user’s email address, which they must enter in the captive portal to access the network. 
  • How It Works: When users attempt to connect, they provide their email address. The system sends a unique OTP to the email, which the user then enters in the captive portal for authentication. 
  • Example: A guest connects to the Wi-Fi at a hotel, enters their email address, and receives an OTP to access the network. 

6. OTP via SMS 

  • Description: Similar to the email-based OTP, this method sends a One-Time Password (OTP) to the user’s phone number via SMS, which they must enter into the captive portal. 
  • How It Works: The user provides their phone number, and the system sends a unique OTP via SMS. The user then enters this OTP in the captive portal to authenticate. 
  • Example: A user connects to the Wi-Fi at an airport and receives an OTP via SMS to access the network. 

7. Social 

  • Description: Social media authentication allows users to log in to the Wi-Fi network using their social media accounts (e.g., Facebook, Google, Twitter). 
  • How It Works: The user clicks on a social media login button (e.g., "Login with Facebook") on the captive portal page. They then authenticate using their social media credentials, which the captive portal validates before granting network access. 
  • Example: A café allows users to log in to the Wi-Fi using their Facebook account, allowing them to use the network after authentication. 

8. Advertisement 

  • Description: Users are required to view or interact with an advertisement on the captive portal before being granted access to the network. 
  • How It Works: Once the user connects, the captive portal displays an ad (often from a third-party provider). Users may need to view the ad for a specific duration or click to acknowledge it. Afterward, they are granted access to the network. 
  • Example: A user connects to Wi-Fi in a shopping mall and is shown an advertisement for a product or service before being allowed to browse the internet.