Every network manager knows the feeling: bandwidth bills climb, guest WiFi feels sluggish, and nobody can quite explain where the capacity is going. On a recent Purple webinar, Helen (VP of Customer Success) and Iain Jewitt (CTO) sat down to answer that question directly - no AI hype, just the real numbers behind Shield, Purple's cloud-based DNS filtering service.
Where does the bandwidth actually go?
According to Iain, roughly 30-40% of typical web browsing traffic is made up of ads and trackers - bandwidth venues pay for but get zero value from. That drain hits hardest in high-traffic environments like train operators and airports, where large volumes of guests (many of them paying for WiFi access) all compete for the same pipe.
Shield tackles this by blocking the domains that serve ads and tracking scripts before they load. The effect isn't just about saving data. Iain pointed out that ad and tracker content is often what actually slows a page down, so once it's blocked, pages load noticeably faster. Purple has measured pages loading up to 3.5 times faster, with up to 40% less data downloaded on web browsing traffic.
▶ Watch clip - bandwidth savings
Real-world results
Helen shared a concrete example: AGS Airports recently switched on Shield's ad and tracker blocking and are now blocking around half a million trackers every week. Manchester Airport Group, another Shield customer, blocks nearly 2 million threats a month. The benefit is twofold: less congestion, and a safer browsing experience for guests, which reflects directly on brand reputation.
Getting started is simple
Shield doesn't require new hardware. It's a cloud-based DNS service: once a venue has a licence, they update their local DNS settings, insert their IP address, and filtering begins immediately. From there, admins choose what to block through Purple's platform.
Beyond ad blocking: security and control
Shield also runs active, AI-powered threat monitoring in real time, rather than relying purely on known-bad lists. It looks for things like newly registered lookalike domains (say, a fake "Gmail" clone) used in phishing attempts and blocks them before they're widely reported. It also protects devices that arrive on the network already compromised - for example stopping an installed keylogger from "calling home" while that device is connected.
Scheduling is another practical control. Venues with tight bandwidth, like trains, can block bandwidth-heavy traffic (think mass OS updates) at peak times or permanently, keeping the network usable when it matters most.
Granular, not just blanket, filtering
Content filtering can go far beyond simple category blocks. Helen described a case where AGS Airports had alcohol-related content blocked by default in family-friendly areas, but reporting showed guests were repeatedly searching for a local distillery. Rather than lifting the whole category, Purple whitelisted just that one domain, keeping the rest of the alcohol category blocked.
This granularity matters most in sensitive settings like local councils and the NHS, where hospitals may need addiction-related content blocked in some areas while other domains stay accessible, avoiding anything potentially triggering. Purple noted the NHS alone sees around 250,000 threats blocked weekly through this setup. Policies can also differ by venue, by user group, or by time of day, letting hotels, for example, allow certain content in guest rooms but not in communal areas.
Why it matters beyond IT
The conversation also touched on workplace use: stripping out ads removes distracting retargeting (like being followed around by ads for something you searched last night) and reduces the risk of exposing personal browsing history during screen shares. And with ongoing public debate in the UK around under-16s and social media, venue operators are under more pressure than ever to know what's reachable on their networks - protecting not just children but less tech-savvy users generally.
▶ Watch clip - content filtering
The takeaway
As Iain put it, Shield hands back bandwidth you're already paying for, improves user experience, and adds protection against threats before blocklists even catch them - all with less ongoing effort. Helen's closing point reinforced the bigger picture: brand reputation and user experience are closely linked, and a guest's first experience of a brand is often their WiFi connection.
Purple is currently offering a 30-day free trial of Shield for anyone wanting to see the impact on their own network. Get in touch to claim yours.
