Now that home automation is firmly in the DIY category and not just reserved as a hobby for our team of engineers, home users are expected to make technology decisions that may be living with them for years. Literally. Once you purchase a large number of devices and realize later that you chose the wrong protocol for your use-case you may have some serious buyer’s remorse being too deep in the investment. This summary will cover the basic technical specifications, a brief description, and the specialty the protocol was developed or designed for. Including the advantages/disadvantages with minimum key features to be concerned about, describing the following:
- Ease of Installation – This will determine the difference between needing to hire a professional contractor for installation versus being able to set it up yourself in a matter of minutes.
- Reliability – IoT reliability refers to the ability of IoT devices and platforms to perform well and transmit data accurately. Reliability depends on factors such as device connectivity, cloud services, hub queries, and latency. A reliable IoT solution should have high availability, low error rate, and fast response time.
- Security – Encryption and overall privacy features meant to protect yourself and your data.
- Scalability – What’s the practical limit on the number of devices you can have on the network before seeing issues like increased message latency, signal loss, etc.?
- Availability and Adoption – Looking at the number of devices available on the market or in development. If the protocol/standard is deprecated or has any future. Some of the popular brands, and (if available) the relative cost of entry. If the protocol is open-source, and the level of consumer development that’s allowed.
This post will give an overview of the following protocols/standards:
Zigbee
- (Typically) 2.4GHz frequency band
- Range: 10-20 Meters indoors, 75-300 Outdoors
- Data Rate: Up to 250kbit/s (2.4GHz band)
- Mesh Network
- Hub/Router/Coordinator is Required. One per network
Zigbee includes a suite of IEEE 802.15.4-based specifications for communication protocols enabling mesh low-power, wireless personal area networks (WPANs) with multi-topology for point-to-point and multi-point-to-point inter-device communication. Developed for use in low-power, low data-rate, and close-proximity embedded applications; it’s become most popular in the Home Automation industry for its low cost of entry, ease of installation, and available connectivity with the use of a cellphone or other popular devices to a central hub. One of the common use-cases for Zigbee is small to medium sized homes with many devices within close-proximity to one another to maintain a strong mesh network. Zigbee also has a minimum battery life of at least 2 years to pass certification.
Advantages
- Stable Mesh Networking with self-healing
- IP Connection for smartphone / tablet control with Zigbee Hub
- Very Low power / long battery life
- Very Cost-Effective
- Secure 128-bit AES Encryption
- High Scalability that supports large number of devices/nodes (1000+)
Disadvantages
- Poor Range
- Interference from Wi-Fi and Bluetooth networks on the same bandwidth
- Mesh Network due to its range the less devices there are the weaker the mesh. Meaning you may have to purchase more devices than you wanted to have a stronger network across the entire home.
- Compared to other options, Zigbee can be more complex to setup, manage, and automate depending on Hub choice (especially for large networks).
Ease of Installation – Most devices install to the network in a matter of minutes but may require extra care and setup for automation features or mesh considerations.
Reliability – The reliability of the network is heavily dependent on where the devices are placed, and how many devices are on the network. To create a strong network, one should have as many devices as possible, where obviously the caveat becomes cost creep.
Security – Zigbee overall has decent security, but has a few flaws which can be explored in much more depth here: Zigbee Security.
Scalability – One of the biggest advantages to Zigbee is the sheer number of devices you can have on the network. It’s been noted that adding devices into the 1000s will begin to hit the practical limit of the protocol.
Availability and Adoption – There are currently 5000+ different Certified Products available on the market. With some of the big name-brands such as IKEA, Honeywell, Philips, Sonos, Amazon, Yale, Bosch, Belkin, Samsung, and more available. The entry-level cost (Hubitat hub, and a cheap lightbulb) is approximately $150-$200 as of this writing. High-end smart home solutions such as Control4 use Zigbee as their underlying technology.
Z-Wave / Z-Wave Long Range (LR)
- Frequency: 800-900MHz (Depending on region)
- Range: 100-800 meters, and 1.6km+ Z-Wave Long Range
- Data Rate: Up to 100kbit/s
- Mesh Network (Star Topology in Z-Wave Long Range)
- Hub is Required. One per network
Z-Wave was initially developed by Zensys in 1999 as a proprietary system on Chip home automation protocol. Z-Wave was limited to 232 devices and -1 dBm PHY output power, until the introduction of the Z-Wave 700 series chips which introduced Z-Wave Long Range [1]. The Z-Wave LR changed the Z-Wave network from a Mesh to STAR network and increased the range from 100 meters per hop to a field proven range of 1 mile at a +14dBm direct line-of-sight as well as 4,000 device maximum. The usage of Z-Wave LR is not mutually exclusive with the use of Z-Wave as the two can coexist on the same network. Z-Wave is extraordinarily popular with Home Automation security-centric devices such as door-locks, garage-openers, and sensors. Due to the closed nature of the protocol, there is an increased level of security. Although similar to Zigbee, see here for a general overview of differences in Zigbee vs. Z-wave
Advantages
- Ease of installation and setup
- Outstanding Range
- Relatively low power consumption
- Stable Mesh Networking with self-healing
- IP Connection for smartphone / tablet control with Z-Wave Hub
- Very Cost-Effective
- Secure 128-bit AES Encryption
- Closed source with S2 Security Authentication
Disadvantages
- Slightly more expensive than Zigbee
- Some Z-Wave devices may be more expensive due to the higher cost of more stringent device certifications by the Z-Wave Alliance
- Slower speed makes it unsuitable for applications requiring high data rates such as video streaming.
- Heavily reliant on hub controller, if it fails the entire network goes down.
- User Experience largely varies based on purchased hub. From personal experience: Hubitat and SmartThings are great hub manufacturers… And they’re both compatible with Zigbee.
- Z-Wave Chip Series are very important when determining what device to buy. The latest series 800 promises significant improvements over 700 series, however, older series congest the network with slower speeds, and may end up being phased out meaning you may need to upgrade your devices over time.
Ease of Installation – Most devices install to the network in a matter of minutes and Z-Wave offers a Quick Start option which allows you to scan a QR code for even faster inclusion into the network.
Reliability – The reliability of the network is less dependent on where the devices are placed than Zigbee, and more so how many devices are on the network with a maximum of 232 (which is sufficient for most homes).
Security – Z-Wave S2 security is one of its main selling points to a lot of home automation or IoT enthusiasts who value their privacy.
Scalability – With a maximum of 232 devices there is a lot of room to play with. However, if you are planning to breach this threshold (which is unlikely for small to medium sized homes) then another option may be more well-suited.
Availability and Adoption – There are (currently as of Oct 2023) 4314 interoperable Z-Wave products throughout the world with over 94 million Z-Wave products sold. Check here for the exhaustive Catalog of Certified Z-Wave Products. There are open-source options for Hubs such as Home Assistant which can be hosted on a Raspberry Pi 3+, container, or practically any platform of equivalent or greater horsepower that runs Linux.
Matter over Wi-Fi®/Thread
- Frequency: 2.4GHz
- Range: 10-20 Meters indoors, 75-300 Outdoors
- Data Rate: Up to 250 kbps
- Mesh Network (Thread), Star Topology (Wi-Fi)
- Hub not required (Wi-Fi), Required for Thread
Matter was developed to be the “Esperanto” of the Home Automation industry as the interoperability protocol for connecting platforms (instead of just devices). Beginning as a joint venture in 2019 between the Connectivity Standards Alliance (responsible for Zigbee) and other big-name brands such as Amazon, Apple, Google, and Samsung SmartThings®. Where Thread is a network protocol, Matter is the device standard. Matter is independent of Thread and can be used without Thread, but both are seeing more use as a replacement or addition to Wi-Fi or ethernet networks. Click the link for a great in-depth Thread Mesh Network Performance analysis made by Silicon Labs (responsible for Z-Wave). Although in its infancy at the time of writing, the Matter/Thread standard looks very promising to dominate the market of Home Automation and Internet of Things.
Advantages
- Interoperability – An agreed upon standard already supported by big name brands like Amazon, Apple, Google, Samsung, etc. which should allow great focus on compatibility between brands.
- Ease of installation especially for adding to existing Wi-Fi networks
- Open-Source Standard for continued review and community improvement
- Same security features with improvements as Zigbee (AES 128-bit encryption).
- Because Matter runs over existing technologies like Wi-Fi, Bluetooth, Ethernet, and Thread, many existing smart home products can and will be updated to support Matter via software updates.
- Has ability to work offline – Everything connects to a local network via Wi-Fi, Thread, or Ethernet and allows for local control even when offline.
- Superior Connectivity using the combination of Mesh (Thread) and Star Topology (Wi-Fi/other) Matter greatly improves communication to devices and compatible hubs.
Disadvantages
- Still in development and (currently) not a lot of Matter specific devices yet.
- Use in highly congested 2.4GHz band
- Potential loss of certain features; For example, Apple Home’s Adaptive Lighting feature works with Philips Hue bulbs if you connect your bridge to Apple Home through HomeKit, but not if you connect it to Apple Home through Matter [2].
Ease of Installation – One of the main focuses of the standard was interoperability and ease of installation for consumers. Arguably one of the easiest to understand for beginners and those who are not technically inclined and/or already have an existing network. Matter will not replace existing platforms but creates a standard language allowing them to work together. Any device that is currently using Wi-Fi, Thread, or Ethernet has the potential for Matter Compatibility.
Reliability – This standard has been largely unreviewed (as of this writing) by the community, and it mostly seems to focus on the interoperability of different protocols rather than the hosting of devices.
Security – Zigbee 2.0. Matter has AES 128-bit encryption using public key cryptography, built by the Zigbee manufacturers with a substantial number of different certifications, and open source for quickly addressing security-related issues.
Scalability – It connects other platforms but depends on the underlying IP protocol I.e., Thread, Wi-Fi IPV6, etc.
Availability and Adoption – Still very new, but very promising with big names already pledging to adopt and support the standard built atop their own current respective standards. The very cheap cost of entry makes Matter very attractive, especially if you have an existing network only needing a compatible hub/bridge; but with limited development here is every device that works with Matter.
Wi-Fi®
- Frequency: 2.4GHz (Most common), 5GHz, or 6GHz depending on generation
- Range: 30m indoors, 120m outdoors
- Data Rate: Up to 6933 Mbit/s (802.11ac a.k.a. Wi-Fi 5),
9608 Mbit/s (802.11ax a.k.a Wi-Fi 6/6E),
or 46 Gbit/s (802.11be a.k.a. Wi-Fi 7)
- Star Topology / Typically Non-Mesh Network
- Hub/Router not required in all cases but highly recommended.
Wi-Fi® is a short name for Wireless Fidelity and was standardized by IEEE with the 802.11 protocol which initially released in 1997 with a large focus on interoperability and fast link speed. Extraordinary speeds with easy/familiar operation makes Wi-Fi a fantastic option for beginners with little to no Home automation experience. However, this will slow down the rest of the network and creates some network privacy concerns which is a large caveat for some. To see what your actual Wi-Fi speeds are, I recommend visiting a site such as fast.com.
Advantages
- Interoperability – It is and has been industry standard for many years. Even your fridge can connect to Wi-Fi nowadays.
- Ease of (wireless) installation – Very easy depending on wireless device.
- Unrivaled Speed
Disadvantages
- High Cost – Even though Wi-Fi is very popular, it’s still on the more expensive side of Home Automation.
- Higher security risk
- Congested 2.4GHz band.
- High power consumption on most devices, and may render most devices not “truly” wireless requiring a power supply. This is only a problem if you hate wires and higher electricity bills.
- Devices may fail when not connected to the internet – Some devices such as security cameras require an internet connection for cloud use.
- Privacy – Since your Wi-Fi network typically has access to the internet you are much more vulnerable to cyber-attacks or data leaks. This is particularly concerning with security cameras and especially indoor cameras
- Intermixed Data – There isn’t any separation of IoT data, and private internet data.
- No standard command structure – Meaning there is no cohesive way to control one device with another, and most devices have their own control features / apps.
Ease of Installation – This really depends on the types of devices you purchase but is straightforward for most devices. Most devices also have their own proprietary apps.
Reliability – One failed device could slow down the entire network, but for the most part Wi-Fi is a solid choice for constant, high-speed data given proper placement and setup of reputable devices. Ideal for devices that require data streaming.
Security – Due to their necessity of being lightweight network components there is not a lot of built-in computational power dedicated to security as compared to traditional desktop computers. With this in mind, these devices usually have direct access to the internet and are directly accessible or vulnerable to hackers on your network.
Scalability – Depending on your bandwidth and speed, roughly 250 total devices (including your computer, tablets, phones, etc.) is the maximum number of devices before detrimental network performance.
Availability and Adoption – Wi-Fi is currently one of the most popular networks around the globe, maybe behind cellular networks. Many today probably couldn’t tell you the difference between the internet and Wi-Fi since they’ve become so synonymous with each other.
Bluetooth® Low Energy (BLE)
- Frequency: 2.4GHz
- Range: 30m indoors, 120m outdoors
- Data Rate: Realistically about 100Kb/s
- Mesh Network (with added BLE Mesh)
- No Hub required
While Bluetooth® Classic and Bluetooth® Low Energy (BLE) protocols share the same 2.4Ghz band, the two are not compatible but some devices implement both protocols. BLE is designed for ultra-low power and low data throughput requirements. Most Ideal for lighting, wearables, or other battery powered low data-rate requirement devices.
Advantages
- Very low power consumption
- Low Cost
- Small sized devices (Typically)
- Compatible with your Smartphone
Disadvantages
- Narrow Use-case – Only for use in special cases like sensors that specifically require extremely low power, close proximity, and don’t need continuous streaming of data.
- Poor Range
- Poor Data-rate
Ease of Installation – Most devices have their own proprietary application to interface with it which is not ideal for having many devices.
Reliability – BLE itself is fairly reliable, but the developers using the Android or iOS Bluetooth stack are usually to blame.
Security – There are some flaws in the security features making it not stack up very well versus other protocol. However, many steps have been taken to correct security issues but it’s still in continuous development.
Scalability – Mesh networks are highly scalable.
Availability and Adoption – Every modern smartphone has Bluetooth capabilities which is usually the control point. However there may not be many devices suited to fit your specific need.
HomeKit®
- Frequency: 2.4GHz (Built on Wi-Fi, Bluetooth, and/or Thread)
- Range: Depends on device/hub
- Data Rate: Depends on device/hub
- Mesh Network
- Proprietary Apple Hub (Apple TV® digital media provider, HomePod® speaker / HomePod mini® speaker) required.
HomeKit® (or Apple Home) is Apple’s standard software and hardware technology for Home Automation and could be a viable option for those enthusiasts who absolutely need their home to contain Apple products. Using Bluetooth and Wi-Fi protocols, HomeKit is a software framework that lets users control everything Apple from the Home App, where you can designate rooms, name devices, and set up routines. Any device that uses HomeKit can also be controlled with Apple’s voice recognition software Siri®. For the record and disclaimer: I do have an iPhone®(mobile digital device).
Advantages
- Integration – Apple products’ integration is fantastic. Such as giving the ability to give authentication via Face ID®(secure authentication) or Touch ID® (fingerprint identity sensor) for unlocking doors or the ability to use Siri.
- Great User Experience – UI is straightforward and very simple.
- Matter support for greater interoperability.
- Open-Source Accessory development kit
Disadvantages
- Interoperability – If you have any IoT devices that are not enrolled in the MFi Program, then good luck getting it to work without Matter/Thread. Even with Matter users have reported feature compatibility issues.
- Very High Cost – Apple products and certifications are notoriously expensive, which in turn passes the cost on to manufacturers developing devices compatible with HomeKit, and thus, consumers.
- Lackluster device support – Currently, there’s simply not enough devices or feature support to justify having it as the home’s primary protocol. It doesn’t seem too hopeful with the rising cost of devices, and other alternatives being more convenient and cost effective for manufacturers.
- Siri – Apple is trying very hard to make Siri the forefront of control for HomeKit. Which would be fine (depending on who you ask), if only talking to Siri wasn’t an awkward, clunky experience.
Ease of Installation – Apple by far has some of the easiest to navigate user experiences out there. Including using their Apple TV as a home hub making setup a breeze.
Reliability – Apple’s reliability is rooted in its consistency. Many of the devices are forced to integrate into the Apple ecosystem by the classic “My way or the highway” approach which has made the ecosystem very robust. However, don’t try to interact with a device not from the Apple ecosystem or it ruins the magic.
Security – Apple’s biggest focus and arguably their greatest strength is their security.
Scalability – Being built on several different protocols (Wi-Fi, Thread, Bluetooth) really helps the case of scalability.
Availability and Adoption – Many of the big-name brands are compatible with HomeKit, and with the introduction of Matter it may grow. However, here is the current exhaustive list of every device compatible with HomeKit, and AirPlay®(software feature).
Summary
- Zigbee: Zigbee is a good choice if you have a large number of devices that require low power consumption and long battery life. However, customers report poor interoperability and frequent connection drops.
- Z-Wave: Z-Wave is a good choice if you have a large number of devices that require low power consumption and long battery life. It is also ideal for devices that are far away from the hub. However, suffers from slow speeds rendering it unsuitable for video streaming or other high-speed applications.
- Z-Wave Long Range: Z-Wave Long Range is an extension of the Z-Wave protocol that offers longer range and lower power consumption than the original Z-Wave protocol.
- Matter: Matter is a good choice if you want to use an open standard protocol that is compatible with multiple smart home platforms.
- Thread: Thread is a good choice if you have a large number of devices from different protocols that require low power consumption. Joining an easy to manage network with high-level interoperability.
- Wi-Fi®: If you have a large number of devices that require high bandwidth and low latency, WiFi is a good choice. However, it can be expensive and may not be suitable for low-power devices. If a device misbehaves, it can slow down the network as a whole. Furthermore, your personal and private Wi-Fi data is intermixed with IoT data.
- Bluetooth® Low Energy (BLE): BLE is a good choice if you have a small number of devices that require low power consumption and short-range communication. However, is in the same bandwidth as Wi-Fi potentially causing or being affected by interference in homes with lots of devices.
- HomeKit®: HomeKit is a good choice if you have an iOS device and want to control your smart home using Siri.
Featured image credit: Copilot Designer.