When people ask how I make my dashboards and monitoring tools available on the public web without exposing my home network, the answer is straightforward: I apply the principles of a data diode system.

What is a data diode?

A data diode is a security mechanism that enforces one-way communication. Data can flow outward from a secure zone, but no inbound traffic is permitted. Originally designed for military, government, and industrial control networks, data diodes guarantee that protected systems remain isolated, even in the event of a breach on the external side. By eliminating bidirectional communication, the attack surface is dramatically reduced.

My network architecture

To apply these principles at home, I have structured my environment into three distinct network segments:

All raw data from devices such as my solar inverter, EV chargers, and monitoring sensors is processed internally. No system on the public-facing side has direct access to the internal cabled or Wi-Fi networks.

Only sanitized and structured JSON payloads leave the secure side. These are transmitted through the firewall into the public-facing webserver, where they are published for dashboards and external monitoring. Access from the internet is strictly limited to this server and to the VPN, which provides an authenticated and controlled path for administrative purposes.

Why I use this approach

Consumer smart home deployments often prioritize convenience over security. Many rely on vendor cloud platforms or open router ports for remote access. Both approaches introduce unnecessary risks by exposing internal devices directly to the internet.

By contrast, my architecture ensures strict separation. Even if the webserver or VPN were compromised, the attacker would gain no foothold inside the cabled or Wi-Fi networks. The maximum impact would be manipulation of JSON data or dashboards — not access to the systems that generate it.

A critical infrastructure mindset

The design is directly inspired by practices in industrial control and critical infrastructure environments. In those domains, operational technology networks are physically or logically separated from IT systems, and unidirectional data flow is standard. By adopting similar principles at home, I create a network posture where the core remains protected and only minimal, sanitized information is published externally.

Beyond the home environment

At first glance, such a setup may appear excessive for a residential network. However, working in IT for more than three decades has shown me the value of staying ahead of security trends. Even though my current professional role is in a different area of IT, I deliberately apply modern security practices in my private infrastructure. This serves a dual purpose: it keeps my systems resilient against potential threats, and it allows me to remain actively engaged with evolving security concepts. It also ensures that, should an interesting opportunity in the security field arise, I am prepared with current knowledge and hands-on experience.

Conclusion

By implementing a layered architecture with two protected internal networks and a hardened public-facing zone, I achieve both resilience and flexibility. The use of data diode principles eliminates inbound risk, restricts external exposure to a single controlled surface, and ensures that my internal systems remain fully isolated.

This may be more rigorous than most home networks require, but it reflects a professional approach: protect the core, control the flow of data, and design with resilience in mind. In doing so, I not only safeguard my own systems but also continue to strengthen expertise that is increasingly valuable in today’s security landscape.