Smart tech has come a long way in the five years since Amazon introduced Alexa to the world. What originally felt like a novelty or passing trend has now become an integral part of the home for many families. In August 2018, 32% of Americans reported owning a smart speaker, and it’s clear our comfort with smart devices and automation is only going to grow.
But something often overlooked by both smart gadget newcomers and seasoned owners alike is how these devices actually talk to each other. You’ve likely heard of using Wi-Fi or Bluetooth to connect the smart devices in your home to each other and the internet, but those wireless networks are just the tip of the home automation iceberg.
Along with the most popular — Wi-Fi and Bluetooth — Zigbee and Z-Wave are two standards that work especially well for smart home automation. Both operate at lower data rates and offer longer battery life than Wi-Fi and Bluetooth. While all of this sounds simple on the surface, how Wi-Fi, Bluetooth, Zigbee, and Z-Wave actually work and the differences between them can get confusing.
The good news is that better interoperability is on the horizon. We asked Lee Odess, Vice President, Solutions Providers Business at Allegion (maker of Schlage locks) if Wi-Fi and Bluetooth would ever give way to Zigbee and Z-Wave in home automation ecosystems, and he believes there’s room for all standards to live in harmony: “Overall, the trend will be eliminating the difference to simplify the decision for homeowners. This is something that consumers shouldn’t have to worry about and brands are aggressively working towards more versatile solutions.”
Until that interoperability is more widely available, though, you’ll still have to pick. To give you the tools you need to make the best call for the future of your home automation, we took a deep dive into the details of what Wi-Fi, Bluetooth, Zigbee, and Z-Wave actually do, how they work, and whether they can coexist in the same ecosystem.
Arguably the most popular wireless standard, Wi-Fi has one of the longest ranges (up to 150 feet on a 2.4 GHz band) and is powerful enough to connect tech like laptops, smart TVs, and video game consoles to the internet. While Wi-Fi is traditionally akin to a radio — transmitting from a set location in your home with a greater frequency strength the closer you are to the router — mesh routers are available to enhance your Wi-Fi network by eliminating dead zones and providing a stronger connection no matter where you are in your home.
A major benefit of using a Wi-Fi network for your ecosystem is that it’s so common — you likely already have Wi-Fi in your home, and there’s no need for an additional hub since smart devices connect via your router. Many devices are also Wi-Fi-compatible, making it easier incorporate the ones you want.
Traditional Wi-Fi does have its limitations. If you plan on building a large ecosystem connecting several different smart devices, then you’ll likely want to go with a different network. Because Wi-Fi eats up a lot of power, your connected devices will require new batteries fairly often. Additionally, having too many devices on your network may slow internet speeds to a crawl.
If you want a simple ecosystem, like a Nest thermostat, Google Home, and a couple Wemo smart plugs, then your existing Wi-Fi network should be able to handle it with minimal lag. However for more extensive home automation that involves several smart devices, a different wireless network is your best bet.
Bluetooth comes in three classes differentiated by transmit power and range. Class 2, the most common range, encompasses devices like wireless mouses and headphones. These kinds of devices are Bluetooth-enabled (equipped with transmitters and receivers), which lets them connect with other compatible devices. Bluetooth devices connect through what is referred to as a “master-slave relationship.” A “master” device — like a smartphone or laptop — can connect with up to seven “slave” devices (headphones, keyboard, computer mouse, etc.). Bluetooth has a range of up to 33 feet and transmits at 2.5 mW. Like Wi-Fi, Bluetooth mesh networking can extend this range and allows for more scalability. While Bluetooth mesh networking is currently seen as a solution for commercial building and factory automation, it’s expected to be widely available to consumers this year.
One of Bluetooth’s biggest bonuses is that it’s energy efficient. Unlike with Wi-Fi, devices connected with Bluetooth have a longer battery life and won’t need constant recharging. Bluetooth-enabled smart devices are also popular–– major brands like Nest, Schlage, and Amazon make their gadgets compatible with the network.
While you don’t need a smart hub to locally control your Bluetooth devices — all you need is a smartphone — you’ll need to invest in one if you want to remotely control your smart home. Bluetooth also has some compatibility issues. Because there are different versions of the standard, it can be difficult pairing devices.
As Bluetooth continues to evolve, expect it to become more ubiquitous in automation — especially as Bluetooth mesh networking expands into the home.
Zigbee and Z-Wave
While Zigbee and Z-wave may be lesser-known wireless standards when compared to Wi-Fi and Bluetooth, they’re extremely popular for home automation. Part of this popularity is because Zigbee and Z-Wave don’t need much power, so batteries last a long time without needing to be changed out. Both also use mesh networking to connect devices throughout a home. They’re more effective than traditional Wi-Fi because devices don’t need to be within range of a hub or router to connect. Instead, devices only need to be within range of one another to establish information pathways. When a hub gets a signal, this signal will hop between devices to relay the message. For example, when you tell your Alexa to lock the front door, the command will jump from device to device until your smart lock receives the communication. And the more “repeater” devices you have, the stronger your network.
While there aren’t many differences between Zigbee and Z-Wave, there are a few you’ll want to consider before choosing a network for your ecosystem. A Z-Wave network can connect up to 232 devices, whereas there’s no device limit with Zigbee. It’s also worth mentioning that Z-Wave-only devices and Zigbee-only devices can’t communicate with one another. Zigbee talks to Zigbee and Z-Wave talks to Z-Wave, there is no Zigbee-to-Z-Wave compatibility.
A key difference between Zigbee and Z-Wave is each network’s level of interoperability. Because the Z-Wave Alliance is privately owned, Z-Wave is a closed, proprietary standard. The Z-Wave Alliance ensures all Z-Wave certified devices are guaranteed to communicate with one another. While there is a Zigbee Alliance, the network is an open standard and has several different Zigbee profiles (Building Automation, Input Device, Light Link, Network Devices, Home Automation, Smart Energy, Telecommunication Services, Health Care, and Remote Control). Zigbee devices from Brand A might not always work with devices from Brand B if they don’t fall within the same profile. This is being rectified, however, so interoperability between Zigbee devices should start improving.
Ultimately, their low-burn power and extensive connectivity make Zigbee and Z-Wave the best wireless networks to build robust smart homes.
How These Wireless Networks Compare
Which standard should I use?
When it comes to choosing a wireless network for your automation system, the choice really comes down to which smart hub or voice assistant you want to incorporate in your home. “From a smart lock perspective, choosing Z-Wave vs. Zigbee or WiFi vs. Bluetooth, is primarily based on the homeowner’s existing gateway,” Odess says. “Homeowners should start by identifying what kind of home control and use case drivers they’d like to have (i.e., Amazon, Google, Apple, etc.), then based on their preferences, select the communication protocol these devices support. In some cases, you might choose a mix.”
Which wireless networks do my smart devices use?
There’s a chance that the smart devices you currently own are compatible with a couple different wireless networks. The best way to figure out if your Nest Camera and Smartthings Hub work on the same standard is by checking the specs. Most brands will list which standards their products work with right on the box. But if you no longer have the box, check the manual or brand’s website for more information.
What about 5G?
Between AT&T’s looming lawsuit and CES 2019’s exhaustive coverage, there’s been a lot of buzz around 5G. Low-latency and fast speeds make it seem like a no-brainer for home automation. Despite this, the future of 5G in the smart home is uncertain. Many brands in the industry are hesitant about 5G and refuse to even comment on it. If companies do get on board, however, 5G has the potential to provide an even better home automation experience then we have today.
Do exclusive partnerships between brands impact compatibility between devices and wireless networks?
Brand partnerships shouldn’t affect network compatibility, but they can affect which devices communicate with one another. For example, because Nest is owned by Google all Nest devices work with Google’s suite of smart products (such as the Google Home or Chromecast). But not all Nest devices integrate with Amazon products. Odess explains: “…[T]hese partnerships accelerate consumers’ willingness to adopt these technologies, but there is a tipping point where if it continues it will degrade innovation, trust, and options. For now, everything is operating smoothly, but [if] it continues to aggressively speed up innovations, long term, it can be a problem. I believe it will slow down and partnerships will become more prevalent.”
When building out your home automation system, consider which devices you want to include and research if the brands you’re interested in are not only compatible with your wireless standard of choice, but with other brands you want to integrate into your home as well.