Comparing The Best Smart Home Network Protocols in 2019

When setting up your smart home, you need to consider the connectivity protocols IoT devices use. Zigbee, Z-Wave, Thread, Bluetooth and WiFi all can connect your devices, but they have some important differences.

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Network Protocols zigbee z-wave thread bluetooth mesh and wifi repeated over and over in front of squiggly lines
Illustration: © IoT For All

There are many reasons why the smart home industry is so fragmented in 2019. Some are practical and others are selfish. Market share is the order of the day, which means every company is clamoring to make their chosen product <> protocol pairing the one to beat.

This makes the proposition of building a smart home potentially frustrating for homeowners, as each piece of the puzzle must be able to “talk to” the others for the best experience.

With that in mind, let’s look at the top smart home protocols in 2019 and explore why some are better than others.

Zigbee

Zigbee is an open-source standard developed by the Zigbee Alliance. This protocol allows for the creation of a mesh network, which means signals “jump” from device to device throughout the home without “dialing out” to a WiFi network first.

This setup requires a central hub, which in turn requires a persistent internet connection, even if the “satellite” devices do not. There is theoretically no limit to the number of times the signal can be passed from one device to the next.

One of the bigger downsides of Zigbee is that it’s a fragmented ecosystem. It supports home automation, smart energy, hospital care and other product families, but each category uses a different variation on the protocol and is not currently compatible with the others. Another drawback is that Zigbee’s frequency can “compete with” WiFi signals.

The list of products that currently support Zigbee includes Amazon Echo and Philips Hue devices, plus gadgets offered by WeMo, Hive and Belkin.

Z-Wave

Unlike Zigbee, Z-Wave—developed by Silicon Labs—is now an open standard. The upside is that every device powered by Z-Wave is compatible with every other. Like Zigbee, Z-Wave is a mesh network—but it limits the number of times the signal can pass between devices to four. Z-Wave presents less risk of traffic “congestion” compared to Zigbee.

Also of note is Z-Wave’s relatively lower throughput. Z-Wave is slower than Zigbee but has a wider operational range. The tradeoff is that each Z-Wave device is less power-hungry than comparable devices under the Zigbee protocol. It’s also worth noting that the Z-Wave standard has changed hands several times, which sends mixed messages about its potential longevity.

Z-Wave is the protocol of choice for SmartThings as well as Lowes’ Iris product lineup. It’s also used by Belkin and can be found in Kwikset and August smart locks.

Thread

Thread is a relatively newer smart home protocol designed to compete with Zigbee and Z-Wave. It was developed in tandem by Qualcomm, Samsung, Nest and others. Thread is also a mesh networking system, but its defining feature is the ability to continue working even when WiFi is unavailable. On the other hand, Thread, like Zigbee, may interfere with devices communicating on the 2.4 GHz WiFi band.

Like Zigbee, Thread is built using open standards—including IP (“Internet Protocol”) — and communicates on the 802.15.4 radio standard. It can be used to facilitate communication between devices or between devices and the cloud. The device’s creators boast that Thread-certified products must be built from the ground up to comply with mandatory security features.

Thread stands out from its competitors because Zigbee and Z-Wave aren’t IP-based. In other words, they don’t work directly with 4G, WiFi or Ethernet. Thread does.

As mentioned, Nest (owned by Google) played a major role in getting this protocol off the ground. There are many other companies with membership in The Thread Group, including Amazon, Google, Apple, D-Link, Kwikset, Nest, Bosch, Yale and Samsung.

Bluetooth Mesh

Everybody knows about Bluetooth. It’s included in every smartphone and laptop, plus an ever-larger selection of speakers and other gadgets. It’s also a rising star in the battle for smart home protocol dominance.

Bluetooth Mesh is based on a standard called Bluetooth Low Energy, most recently championed by Bluetooth 5.0. And as the name suggests, it provides mesh connectivity like Zigbee and Z-Wave. It also shares Zigbee and Z-Wave’s disadvantages compared to Thread—Devices using this protocol aren’t addressable using the IP standard.

Under small network payloads, Zigbee, Z-Wave and Bluetooth Mesh yield similar results for speed and latency. However, Bluetooth sees diminishing returns as its network grows busier.

The biggest advantage of Bluetooth is name-recognition and the fact that it’s virtually everywhere. It should be noted, however, that only devices with Bluetooth 4.0 or 5.0 support the mesh communication protocol.

Despite this name recognition, Bluetooth Mesh is, for all intents and purposes, a new technology. It doesn’t have the robust product ecosystem of some of the other protocols, and for these devices to communicate with the outside world, homeowners need a hub device to bridge their local Bluetooth Mesh network with IP protocols like cellular or WiFi.

WiFi

Just about every home has a wireless network these days, which means WiFi can be the most cost-effective and accessible way to build out your IoT network. One of the downsides of WiFi as a smart home protocol is that deploying many devices on the same network can cause interference. Other problems include security and—for indoor positioning systems—accuracy.

For smaller IoT networks, however, WiFi shines. It excels at sending large amounts of data quickly, though this comes at a cost of higher energy consumption than other protocols. For devices that remain plugged in all the time rather than rely on batteries for power—including home security systems—WiFi is an obvious choice.

Interestingly, future innovations may result in WiFi performing better than some of the others—WiFi HaLow and WiFi HEW both seek to address WiFi’s high power consumption.

How Much Longer Will Smart Homes Be Fragmented?

In its 2018 “Connected Home and Building Technology Trends” survey, Jabil found that 97 percent of respondents believe their businesses would benefit from, rather than be hurt by, efforts to bring standardization into this industry.

Some smart home hubs do allow Z-Wave and Zigbee products to work in tandem, but you have to know what to look for.

The concept of interchangeable parts in physical products dates back to the late 1700s. But, just because some of today’s key technologies are invisible, doesn’t mean the idea is any less relevant today than it was then.