The Case for Segmented Networks

When you’re diving into the world of home automation, the foundation of your smart home begins with the network. It’s the lifeblood that connects devices and makes everything, well, “smart.” But here’s the catch—there’s more than one way to set up a smart home network, and they’re not mutually exclusive. You can run multiple networks in harmony. Let’s walk through why The Almost SmartHome runs its network primarily on Zigbee and how you can optimize your own setup for the best experience.

The Heart of the Network: The Hub To manage your smart home devices, you need a hub. Think of it as the “command center” for your smart network. The Almost SmartHome runs on a Zigbee network with a Conbee II stick[Amazon] plugged into a Raspberry Pi[Amazon], running Home Assistant. For simplicity’s sake, the goal is to centralize everything on this single hub, keeping things smooth and efficient.

Advertisements Wi-Fi vs. Zigbee: Why We’re Skipping Wi-Fi for Most Devices Experience has taught us one important lesson: avoid Wi-Fi devices when possible. While some devices (like cameras and locks) don’t offer alternatives, relying on Wi-Fi often adds unnecessary complexity. You’ll need to configure your router to ensure they can’t “snoop” into other parts of your network. It’s possible, but it’s not pretty. We prefer to keep things simpler with Zigbee, which brings us to why having everything on one mesh network is better—well, most of the time.

Why A Unified Network is (Mostly) Great A unified Zigbee network makes things robust. In Zigbee, powered devices like plugs and switches act as “mini-hubs” or “repeaters,” forming a larger, more reliable mesh network. Here’s how it works: if your door sensor needs to send a message, it finds the nearest powered device (a switch, plug, etc.), which then relays that signal on its way to the main hub. The more powered devices you have, the stronger your network’s mesh becomes.

Sounds ideal, right? Well, not quite. There’s one big wrinkle in this perfect mesh setup: the lightbulbs.

The Lightbulb Dilemma: A Case for Segmented Networks On a Zigbee network, lightbulbs also act as mini-hubs, connecting other devices to the mesh. That’s great—until it isn’t. Most lightbulbs are attached to physical switches. And while smart home purists will tell you to keep the switch “on” all the time, reality doesn’t always cooperate. Someone flips that switch off, and boom—your lightbulb goes dark, taking down all the devices connected through it.

Cue frustration.

You’ll find that automations might stop working for no apparent reason. The network rebuilds itself, but inconsistencies pop up, leading to unreliable performance. While these network drop-offs aren’t catastrophic, they’re undeniably annoying.

The Solution: Separate Lightbulbs on Their Own Hub Now, here’s the trick. By giving your lightbulbs their own separate hub (say, the Philips Hue Bridge), you isolate them from the rest of your Zigbee mesh. Devices like switches, sensors, and plugs can then connect to your primary hub, such as the Conbee II stick. This way, when someone inevitably flips the light switch, your core devices won’t be affected.

    graph TD
	  subgraph Primary Zigbee Hub
	    A1[Plug]
	    A2[Motion Sensor]
	    A3[Door Sensor]
	    A4[Smart Switch]
	    A1 --> Hub1[Conbee II Hub]
	    A2 --> A1
	    A3 --> A1
	    A4 --> Hub1
	  end
	
	  subgraph Lightbulb Hub
	    B1[Living Room Bulb]
	    B2[Bedroom Bulb]
	    B3[Kitchen Bulb]
	    B1 --> Hub2[Hue Bridge]
	    B2 --> Hub2
	    B3 --> Hub2
	  end
	
	  classDef hubs fill:#f9f,stroke:#333,stroke-width:2px;
	  class Hub1,Hub2 hubs;
	
	  subgraph Home Assistant
	    HA[Home Assistant]
	  end
	
	  Hub1 --> HA
	  Hub2 --> HA

Conclusion: Building a Reliable Smart Home Network So, should you separate your networks? It’s not a must, but it’s definitely a smart choice if you’re dealing with unreliable automations. By isolating your lightbulbs from the rest of the system, you’re setting yourself up for a more dependable smart home experience.

Ingredients: Zigbee Network – A low-power, mesh network protocol commonly used in home automation. Hub – The central device that manages and communicates with your smart home devices. Conbee II Stick – A popular Zigbee USB stick that can be connected to a Raspberry Pi to act as a hub. Mesh Network – A network topology where devices can connect to each other to strengthen overall connectivity. Philips Hue Bridge – A dedicated hub for Philips Hue lightbulbs, keeping them separate from other Zigbee devices.