You connected to WiFi in a cafe or hotel and instead of the internet a login page opened? That is a captive portal. You have certainly met it many times. Let us explain what it is, how it works and why venues use it.

What a captive portal is

A captive portal is a page shown when connecting to WiFi before it lets you onto the internet. First you have to do something: accept the terms, log in, enter a code or an email. Only then do you get access. It literally captures you for a moment, hence the name (captive).

How it works

When you connect to such WiFi, the network first redirects you to the portal and blocks other traffic. After you meet the condition (consent, login), the network lets you through. This happens at the network level, so it works on a phone, laptop and tablet.

Where a captive portal is used

You will meet it everywhere WiFi is offered to the wider public:

  • Hotels and guesthouses, where the guest logs in with a name or a code from reception.
  • Cafes and restaurants with WiFi for customers.
  • Airports, stations and transport.
  • Shopping centers and stores.
  • Conferences and events.
  • Companies with a guest network for visitors.

What a captive portal is good for

The portal asks for consent to the terms of use. The operator thereby states the rules and protects itself, since the user confirms they are using the network correctly.

2. Separating guests from the internal network

Guest WiFi via a captive portal tends to be separated from the company network, so visitors have no access to internal systems. This is the same principle as network separation via VLAN and significantly increases security.

3. Access control

The portal lets only authorized people onto the network: guests with a code, customers with a password of the day, event attendees. A time limit or speed limit can also be set.

4. Marketing and insight

Some portals offer login via email or show a welcome page with a logo and an offer. The venue thus gains branding and a contact, of course in line with GDPR and with consent.

A captive portal and security

For a venue, a captive portal is a tool for order and separating guests. For the user, however, it holds that public WiFi with a portal is not automatically secure. The login page does not encrypt your traffic. On an unfamiliar network, caution and a VPN are still useful, more in the article on the risks of public WiFi.

Conclusion

A captive portal is an elegant way to offer WiFi to the public, keep order, separate guests from the internal network and at the same time meet legal conditions. For hotels, restaurants and companies with visitors it is almost a standard.

Do you run a hotel, restaurant or company and want secure guest WiFi with a login page? Get in touch, we will design and set up the captive portal and a separated network.

This article is part of our Computer networks overview.