Glossary

Guest WiFi & Captive Portal Glossary

Plain-English definitions of the terms behind captive portals, guest WiFi marketing, and data capture - written for venue owners, not network engineers.

Captive Portal

A captive portal is a web page that public WiFi users see before being granted internet access - typically used to authenticate users, accept terms, and capture data such as email or social-login identity.

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WiFi Marketing

WiFi marketing is the practice of using a venue's guest WiFi network - typically via a captive portal - to capture customer data and deliver follow-up communications such as automated emails, SMS, review requests, and loyalty offers.

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Guest WiFi

Guest WiFi is a public, internet-only WiFi network a business offers to customers, separate from its private back-office network, typically secured by a captive portal that requires sign-in.

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WiFi Data Capture

WiFi data capture is the process of collecting customer information - typically name, email, mobile number or social-login identity - when a guest connects to a venue's WiFi via a captive portal.

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WiFi Email Capture

WiFi email capture is the technique of collecting a guest's email address as a condition of free WiFi access, typically through a captive portal's sign-in form, so the venue can send marketing communications afterwards.

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GDPR & Guest WiFi

GDPR & guest WiFi refers to the UK and EU data-protection rules that apply when a venue captures personal data via a captive portal - requiring lawful basis, opt-in consent, an accessible privacy notice, audit trail, and the right to erasure.

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Splash Page

A splash page is the branded web page a captive portal shows a guest when they connect to a venue's WiFi, presenting the sign-in form, terms of use, marketing opt-in, and any promotional content before internet access is granted.

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Social WiFi

Social WiFi is guest WiFi that lets visitors sign in with an existing social account such as Facebook or Google instead of filling in a form, giving the venue verified profile data in exchange for internet access.

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Social Login

Social login is an authentication method that lets a user sign in to a service with an existing account from a provider such as Facebook, Google, or Apple, using the OAuth 2.0 authorisation framework, instead of creating a new username and password.

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Review Automation

Review automation is the practice of automatically sending customers a review request - usually by email or SMS a set time after their visit - using contact details captured at the venue, so online review volume grows without staff effort.

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First-Party Data

First-party data is customer information a business collects directly from its own audience with consent, through its own channels such as WiFi sign-ins, its website, bookings, or POS, as opposed to data bought from or shared by other companies.

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Opt-In Rate

Opt-in rate is the percentage of people who actively consent to receive marketing communications during a sign-up flow, such as ticking the unticked marketing checkbox on a WiFi splash page.

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Repeat Visit Rate

Repeat visit rate is the percentage of a venue's guests who return for at least one further visit within a given period, a core loyalty metric that guest WiFi can measure automatically by recognising returning sign-ins.

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MAC Address Randomisation

MAC address randomisation is a privacy feature, on by default in iOS 14+ and Android 10+, that presents a random per-network hardware address to WiFi networks instead of the device's permanent factory-assigned MAC address.

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Captive Network Assistant

A Captive Network Assistant is the mini-browser that iOS, Android, macOS, and Windows open automatically when they detect a captive portal, triggered by a connectivity probe to a known URL that fails to return the expected response.

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SSID

An SSID (Service Set Identifier) is the public name of a WiFi network - a label of up to 32 bytes that access points broadcast so nearby devices can find and join the network.

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VLAN

A VLAN (Virtual Local Area Network) is a logical segmentation of a physical network, defined by IEEE 802.1Q, that isolates groups of devices - such as guest WiFi users and staff systems - from each other while sharing the same switches and cables.

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Access Point

An access point (AP) is a networking device that broadcasts one or more WiFi networks and bridges wireless devices onto a wired network, typically ceiling-mounted and powered over Ethernet in business deployments.

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WiFi Hotspot

A WiFi hotspot is a physical location where people can access the internet over WiFi, provided through one or more access points, with access controlled by a captive portal, password, voucher, or paid plan.

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RADIUS Authentication

RADIUS (Remote Authentication Dial-In User Service) is a network protocol providing centralised authentication, authorisation, and accounting (AAA), defined in RFC 2865, and used by enterprise WiFi, VPNs, and captive portals to control network access.

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Walled Garden

A walled garden, in captive-portal networking, is the allow-list of domains and IP addresses an unauthenticated guest device can reach before signing in - typically the splash page itself plus any social-login, payment, or asset domains the portal needs.

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Passpoint / Hotspot 2.0

Passpoint, also known as Hotspot 2.0, is a Wi-Fi Alliance certification based on IEEE 802.11u that lets devices discover, securely authenticate to, and roam between participating WiFi networks automatically, with no captive portal or manual sign-in.

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PECR

PECR (the Privacy and Electronic Communications Regulations 2003) is the UK law governing electronic marketing messages, cookies, and similar technologies, requiring prior opt-in consent before a business sends marketing emails or texts to individuals - including contacts captured via guest WiFi.

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Email Deliverability

Email deliverability is the ability of a sender's messages to reach recipients' inboxes rather than spam folders or being rejected, determined by authentication (SPF, DKIM, DMARC), sender reputation, list quality, and recipient engagement.

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Welcome Email

A welcome email is the automated first message sent to a new subscriber shortly after sign-up - in WiFi marketing, within minutes of a guest connecting to the venue's WiFi - and it typically achieves the highest open rate of any email a business sends.

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Win-Back Campaign

A win-back campaign is an automated marketing flow that targets customers who have not visited or purchased for a defined period - commonly 60, 90, or 180 days - with a message or incentive designed to bring them back.

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Customer Data Platform

A customer data platform (CDP) is software that builds a persistent, unified database of individual customer profiles by combining data from multiple sources - such as WiFi sign-ins, POS transactions, bookings, and email engagement - and makes those profiles available to other marketing and analytics tools.

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Footfall Analytics

Footfall analytics is the measurement of how many people visit a physical location, when they visit, how long they stay, and how often they return, using sensors such as WiFi access points, cameras, or door counters.

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Dwell Time

Dwell time is the length of time a visitor spends at a location during a single visit, measured in WiFi analytics as the interval between a device first and last being seen on the network.

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Paid WiFi

Paid WiFi is a guest WiFi model in which users buy internet access - by time block, data allowance, or speed tier - through a checkout on the captive portal, common in hotels, holiday parks, marinas, and events.

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WiFi Vouchers

WiFi vouchers are single-use or time-limited access codes that a venue hands out - printed on receipts, room cards, or at the counter - which guests redeem on a captive portal to get online.

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