The transition to a smart home might seem overwhelming, especially when faced with the decision of selecting a superior home automation system. Currently, Zigbee and Z-Wave are recognized as the best wireless protocols available. However, pinpointing the suitable protocol for your smart home could be problematic. Also, how do these protocols measure up against the rapidly evolving Matter standard in terms of compatibility?
In this article, I dive into the differences between Zigbee and Z-Wave to help you make the right decision for your home.
Zigbee vs Z-Wave
What are Zigbee and Z-Wave?
Zigbee and Z-Wave are the predominant smart home wireless communication protocols in the market. Both use a similar mesh network for communication and similar network hierarchies.
Zigbee standards are owned and maintained by the Connectivity Standards Alliance (formerly known as the Zigbee Alliance) and are part of the IEEE 802.15.4 protocols.
Z-Wave was acquired by Silicon Labs from Sigma Designs and is now maintained by the Z-Wave Alliance. Both of these alliances contain manufacturers and researchers that work to make these standards better.
Zigbee and Z-Wave devices differ in their frequencies, wireless ranges, data transfer capabilities, and power requirements. Additionally, since independent alliances maintain these standards, they also differ in interoperability and compatibility.
Zigbee and Z-Wave are not directly compatible with each other.
Comparison Table
Before I get into the full comparison of these technologies, here's a quick overview in tabular form.
| Zigbee | Z-Wave | |
|---|---|---|
| Frequency | 2.4 GHz, 915 MHz (US), 868 MHz (Europe) | 908/916 MHz (US), 868 MHz (Europe) |
| Range | 10-100 meters | 30 meters |
| Bandwidth | 250 kbps | 100 kbps |
| Interoperability | Compatible with IEEE 802.15.4 standard | Proprietary protocol |
| Network Topology | Mesh network | Mesh network |
| Power Consumption | Low power consumption | Ultra-low power consumption |
| Security | AES-128 encryption | AES-128 encryption |
| Device Limit | Up to 65,000 devices per network (in theory) | Up to 232 devices per network |
| Cost | Typically lower cost devices and components | Typically higher cost devices and components |
| Complexity | More complex protocol and network setup | Simpler protocol and easier network setup |
| Compatibility | Wide range of devices from different vendors | Limited devices from specific vendors |
| Signal Reliability | Can be affected by interference from other devices | Less susceptible to interference from other devices |
| Frequency of Updates | More frequent updates and enhancements to the protocol | Slower updates and enhancements to the protocol |
| Latency | Generally lower latency | Higher latency |
| Battery Life | Longer battery life for Zigbee devices | Shorter battery life for Z-Wave devices |
| Device Discovery | Faster and easier device discovery | Slower and more complicated device discovery |
| Industry Standards | Zigbee is an open standard governed by the Zigbee Alliance | Z-Wave is a proprietary standard owned by Silicon Labs |
Frequencies
Zigbee vs Z-Wave devices operate in different frequency ranges. Zigbee operates in the 2.4GHz range worldwide, with the option of communicating at 868 MHz in Europe and 915 MHz in the United States.
Z-Wave operates in various sub-GHz frequency ranges, such as 868 MHz in Europe and 908 MHz in North America, depending on the region.
This difference in operating frequencies is one of the main reasons why Zigbee and Z-Wave devices differ so much in other characteristics.
Zigbee devices are more prone to interruptions by Wi-Fi devices since they use the same frequency range. In contrast, Z-Wave devices are susceptible to disruption by wireless landline signals or baby monitors.
Range
Lower frequencies can penetrate other mediums more efficiently and can also travel a greater distance without deteriorating. Hence, Z-Wave devices generally have a better range than Zigbee devices.
Zigbee wireless signals can travel up to 80m without interruptions, but this range is significantly reduced inside homes due to walls, windows, and any other obstructions. Inside homes, Zigbee's range can drop to 10-20m.
Z-Wave wireless signals can travel up to 100m without interruptions, while inside a house, their range can still get up to 50-60m.
As both technologies utilize a mesh topology, the range of both Zigbee and Z-Wave can be improved using repeaters. Repeaters are devices that can relay data to the devices out of the central hub's wireless range.
Z-Wave Long Range
Z-Wave Long Range (Z-Wave LR) further extends the range and network capabilities of Z-Wave devices. Z-Wave LR enables communication up to several kilometers and can support up to 4,000 nodes on a single network.
As Z-Wave LR devices become more widely adopted, they will provide an even more robust and extensive coverage option for smart home users.
Speed
Zigbee wins in speed! Since Zigbee uses high frequencies, it can transmit more data. Zigbee can reach speeds of up to 250kpbs while Z-Wave usually reaches 100kbps (almost half).
These speeds are significantly lower than Wi-Fi and Bluetooth because Zigbee and Z-Wave devices generally do not need high data transfer speeds. That is because a lot of data being transmitted in smart home networks comes from sensors that only produce a small amount.
Interoperability
Interoperability is one of the most critical aspects of your smart home network. Appliances in a home are continuously being replaced, while new devices are regularly introduced. It can be painfully tedious to go through a wide array of devices to find one that fits your network. That is why both Zigbee and Z-Wave standards are strictly maintained by their respective alliances, which also certify products.
Zigbee is an open-source standard, which means manufacturers are free to use it in their devices without permission from the alliance. The way Zigbee certifications are organized also makes it harder for customers to pick a device.
Manufacturers may certify their hardware with Zigbee but then use non-certified software. Such devices are tagged as “Zigbee-ready” and might not be compatible with your home network. To ensure compatibility, look for devices with the Zigbee 3.0 certification, which guarantees compliance with the latest Zigbee standard, offering better interoperability and compatibility with your home network.
On the other hand, Z-Wave is the property of Sigma Design, which also runs the Z-Wave Alliance. Since Z-Wave is proprietary, manufacturers have to go through stringent certification processes that ensure their devices comply with Z-Wave standards. This is why Z-Wave devices are far more interoperable and backward compatible.
Device Availability
There is a vast assortment of both Zigbee and Z-Wave devices on the market right now. Zigbee standards vary depending on geographical location. For example, Zigbee's frequency range for the US is 2.4GHz, but in some parts of Europe, it might be 968MHz, which is a huge difference.
Z-Wave, on the other hand, has a pretty similar range for most of the world. This is also why you find more Zigbee devices overseas—because vendors in other countries do not have to live by strict alliance standards and have more room to flex their creative muscles.
Many smart home hubs, such as Samsung SmartThings, Homey Pro, and Hubitat, support both Zigbee and Z-Wave devices, so you don't have to choose between them.
Matter Standard
Matter (previously known as Project CHIP) is an emerging open-source smart home standard backed by major tech companies, including Apple, Google, and Amazon.
Developed by the Connectivity Standards Alliance, Matter aims to unify and streamline smart home device communication for better interoperability.
As Matter gains momentum, it is expected to impact the smart home market significantly and could influence the adoption of Zigbee and Z-Wave devices in the future.
As Zigbee is one of the key players supporting Matter, the development of this standard may significantly impact the future of Zigbee-based smart home ecosystems.
For more information on the Matter Standard, check out my article here.
Device Cost
Not much of a difference here, but if you want to get deep into the weeds, Z-Wave devices are a bit more expensive than Zigbee. This is more true for a cheaper device ($10-$500 range), while the price evens out as you get to the higher end of the spectrum.
I believe this is due to how tightly controlled Z-Wave is. Since Zigbee is open-source, small-scale manufacturers do not need to go through corporate channels to use it in their devices, making these devices cheaper.
Z-Wave performs strict compliance tests to ensure that manufacturers using their technology comply completely with Z-Wave standards. In some cases, manufacturers might even get their silicon chips via the Z-Wave Alliance, making the raw products for their devices more expensive.
Latency
I've discussed speed, but what is more critical in a smart home setup is latency. In the context of a smart home, latency can refer to the delay between giving a command and the appliance reacting to it. For example, if you trigger a command to turn off a light switch, and it takes 3-4s for the light to turn off, then that is latency. Latency can be frustrating and will ruin the cozy smart home feeling you're looking for.
While Zigbee protocol is much faster, Zigbee devices do not necessarily exhibit less latency than Z-Wave. The difference will probably be in milliseconds and not noticeable. This is because latency is not only dependent on the speed of wireless communication but also on factors such as compatibility of devices, power consumption, and reliability of the network.
Zigbee networks may experience more delays due to interference from other devices like Wi-Fi.
Network Size & Design
Z-Wave devices can support up to 232 relaying devices (end nodes) only. This is because of the “four-hop rule” for Z-Wave, which means that instructions can only hop four times from device to device in a Z-Wave network.
Zigbee, on the other hand, can theoretically support up to 65,000 devices by continuously adding repeaters. If you are a smart home buyer, 232 nodes will be enough for you, but for users with much larger houses, Zigbee might be the better choice.
It is worth mentioning that Z-Wave Long Range has a much more extensive range and can support a lot more devices.
Power Requirement
For a long time, Zigbee devices used a lot less power than Z-Wave devices. However, this is changing. With the Z-Wave plus specification, Z-Wave devices' power consumption is now quite close to Zigbee’s. It is worth noting that Z-Wave has a more extensive range, which also adds to its power consumption.
When it comes to power consumption in both standards, make sure you're comparing apples with apples. For example, if a Zigbee network has a lot more repeaters than Z-Wave, its overall power consumption will be higher. Similarly, if there is a lot of noise on your frequency channel, your devices will end up consuming more power to recognize the same messages.
Z-Wave Plus v2
Z-Wave Plus v2, also known as 700 Series or Gen7, is the latest iteration of Z-Wave technology, which further improves energy efficiency, range, and security.
Devices featuring Z-Wave Plus v2 offer enhanced features like longer battery life, faster communication, and increased range compared to earlier Z-Wave generations.
Additionally, Z-Wave Plus v2 devices support SmartStart, a feature that simplifies the device pairing process, making it easier for users to set up and manage their smart home networks.
As Z-Wave Plus v2 becomes more widely adopted, it will provide smart home users with a more seamless and efficient experience.
Zigbee Green Power
Zigbee Green Power is a feature within the Zigbee 3.0 standard that enables ultra-low-power devices, such as sensors and switches, to operate on energy harvesting or very low-power sources like coin-cell batteries.
By leveraging Zigbee Green Power, smart home devices can reduce their power consumption and extend their battery life, further enhancing energy efficiency in Zigbee-based networks.
Reliability
In general, Z-Wave is considered to be more reliable than Zigbee, primarily due to its lower operating frequency and more tightly controlled ecosystem.
Z-Wave operates in the 900 MHz frequency range, which experiences less interference from other devices and is better at penetrating walls and other obstacles compared to Zigbee, which operates in the 2.4 GHz range, where Wi-Fi and other devices can cause interference.
Additionally, Z-Wave devices are required to undergo a stringent certification process to ensure they comply with Z-Wave standards, resulting in greater interoperability and more consistent performance.
In contrast, while Zigbee is also maintained by an alliance that certifies products, its open-source nature allows for greater variation in device implementation, which can sometimes lead to compatibility and reliability issues.
This is not to say that a well-designed Zigbee network will still not be reliable, just that Z-Wave networks require less design to be more reliable.
Security
Both Zigbee and Z-Wave put a strong emphasis on security to ensure that smart home networks are protected from potential threats and unauthorized access.
Zigbee 3.0 implements AES-128 encryption, which is a widely used and secure encryption standard. It also includes features like secure key establishment and device authentication, ensuring that only authorized devices can join and communicate within the network.
Z-Wave Plus v2 (700 Series) introduces the Security 2 (S2) framework, which provides advanced encryption and device authentication. S2 offers three levels of security: S2 Unauthenticated, S2 Authenticated, and S2 Access Control. These levels provide varying degrees of security depending on the device's role in the network.
The S2 framework also implements Elliptic Curve Diffie-Hellman (ECDH) secure key exchange to protect against eavesdropping and man-in-the-middle attacks.
Ecosystems and Compatibility
In the past, Zigbee and Z-Wave devices would typically need a hub to be compatible with other popular smart home ecosystems, such as Amazon Alexa, Google Home, and Apple HomeKit.
Amazon has released a number of Echo speakers that have integrated Zigbee radios, allowing you to directly control these devices without needing a hub.
As of the time of writing, Google Home and Apple HomeKit have more limited support for Zigbee and Z-Wave devices, requiring additional hardware like a compatible hub (e.g., Hubitat, Aqara, Philips Hue) or a Homebridge setup to enable integration with HomeKit.
Ease of Setup and Management
Both Zigbee and Z-Wave networks are designed to be relatively easy to set up and manage, with user-friendly device pairing processes, network management, and troubleshooting options.
Zigbee devices typically offer touchlink commissioning, allowing users to pair devices by simply bringing them close to each other. This process simplifies device pairing and makes it easier for users to add new devices to their Zigbee network.
Z-Wave's SmartStart feature streamlines the process of adding devices to a Z-Wave network. Users can simply scan a QR code on the device to add it to their network, eliminating the need for manual pairing procedures.
Additionally, both Zigbee and Z-Wave networks can self-heal, meaning that they can automatically reconfigure their mesh topology if devices are added or removed, ensuring optimal performance.
When it comes to network management, both Zigbee and Z-Wave offer tools and features that make it easy to monitor and control devices, as well as troubleshoot any issues that may arise.
Can I Mix and Match Z-Wave & Zigbee Devices?
Yes, you can! Many modern smart home hubs, such as the Aeotec Samsung SmartThings Hub or Hubitat, are capable of communicating with both Zigbee and Z-Wave devices simultaneously. Keep in mind that while you are using both types of devices simultaneously, you still have two distinct networks.
Zigbee devices can only communicate with other Zigbee devices, and so is the case for Z-Wave. Zigbee repeaters can’t be used for a Z-Wave network or vice-versa. This means you will have both Zigbee and Z-Wave networks in your house and a single hub that will communicate with both of them.
It is pretty helpful to have both networks and then decide which device works well for which network. For example, since Z-Wave is more reliable, you can set up alarm systems and smart locks on it.
Conclusion
Both Zigbee and Z-Wave have their advantages and challenges. When making a decision, carefully evaluate your needs and then choose a technology accordingly. Don't forget, with a smart home hub like Hubitat or SmartThings you can mix and match protocols.
Sources
https://csa-iot.org/all-solutions/zigbee/
1 Comment
Craig LaHote
Table shows Z-Wave range of only 30 meters – should be 100 meters.