Zero trust security explained with hotel metaphor

Zero Trust Explained: The Hotel Key Card Metaphor

“So what exactly is this zero trust thing everyone keeps talking about?” I get this question a lot. Usually from managers, executives, or anyone who has to approve a security budget without a technical background. And most explanations I have seen are terrible. They either drown you in jargon or sand the concept down so far that nothing useful is left. So here is the metaphor I reach for instead. I have used it to explain zero trust to my parents, to executives, and to that one colleague who still calls the firewall “the internet box.” It works because it starts with something everyone has touched: a hotel key card. We will build up from there, one layer at a time, until you can see how the same idea runs all the way down to mTLS and identity-aware proxies. ...

February 19, 2026 · 8 min read · Tom Meurs
SPIFFE workload identity visualization

SPIFFE and SPIRE: Zero Trust Service Identity

How does Service A know that Service B is actually Service B? I keep coming back to that question because the usual answer is uncomfortable. For years we trusted network location. Traffic from the right IP was legitimate, end of story. Zero trust took that assumption out back and shot it. Now every service has to prove who it is, every single request, no matter where it sits on the network. ...

July 26, 2025 · 11 min read · Tom Meurs
Kubernetes Network Policies visual guide

Kubernetes Network Policies: A Visual Guide to Pod Security

Picture this: an attacker pops a single pod in your cluster, maybe through a vulnerable image or a leaked token. From that one foothold, they can reach every database, every internal API, every secret-fetching sidecar you run. Nothing stops them, because by default nothing tries to. Network Policies are the thing that stops them. They turn “one compromised pod” into “one compromised pod, and that’s it.” Everyone knows they should use them. Almost nobody actually does, because the YAML looks scary and the behaviour is weird until the mental model clicks. ...

February 8, 2025 · 8 min read · Tom Meurs