Zigbee is a wireless technology that was developed as an open global standard to address the unique needs of low-power, low-cost wireless IoT (Internet of Things) networks.
It is a protocol used to link smart devices like plugs, smart locks, and lights to a home network
We can also link our Zigbee network to a hub like SmartThings Hub. Here, SmartThings Hub serves as a “bridge” to the Internet, offering apps, cloud tools, and (remote) control from our phones.
However, Zigbee is similar to but different from competing protocols like Wi-Fi, Bluetooth, and Z-Wave.
They all create relatively secure networks, which we can (mostly) connect to a hub and control with our phone or a desktop application.
How does Zigbee work?
Zigbee delivers low-latency communication, and the chips are typically integrated with microcontrollers and with radios. Zigbee devices communicate with each other using a radio transceiver.
Furthermore, every Zigbee device uses the same communication standard, with forwards and backward compatibility.
Zigbee chips operate on the IEEE 802.15.4 protocol, over 2.4 GHz, which we might recognize as the same band used by Bluetooth and Wi-Fi. Zigbee uses less power, so it has a shorter range of about 10-20 meters indoors.
Zigbee builds on the media access control and physical layer defined in the IEEE standard 802.15.4 for low-rate WPANs (wireless personal area networks).
The specification includes four additional key components: application layer, network layer, manufacturer-defined application objects and, Zigbee Device Objects (ZDOs).
Zigbee Device Objects are responsible for some tasks, including managing requests to join a network, device discovery and security, as well as keeping track of device roles.
The Zigbee network layer natively supports both tree and star networks, and generic mesh networking. Every network must have one coordinator device. Within star networks, the coordinator must be the central node.
Both trees and meshes allow the use of Zigbee routers to extend communication at the network level.
- Zigbee devices are capable of connecting to each other.
- Zigbee devices offer backwards and forward software compatibility
- We don’t need multiple hubs to connect more devices
- Zigbee offers device-to-device communication
- Zigbee is a facility for protecting the establishment and transport of cryptographic keys, carrying out secure communications, controlling devices, and ciphering frames.
Mesh Network: A mesh network is fundamentally a network where each device takes on the role of a repeater. In a mesh network, rather than the device sending the signal back to the originator, it repeats the signal and forwards it to all other network devices within range.
Mesh networking can be referred to as “self-healing networks”. With a standard Wi-Fi network, if our router goes offline, all devices also go offline.
Zigbee protocols automatically detect and remediate failures, outages, breaches of all kinds and “self-heal” so devices continue to perform. As long as there is another routing device within range, the network will simply re-route and stay up.
Types of Zigbee Devices
A Zigbee network consists of three device types: the Zigbee Coordinator (ZC), the Zigbee Router (ZR), and the Zigbee End Device (ZED). All these devices play different roles in a Zigbee network.
Let’s take a look at the various roles that the device types perform:
- Zigbee Coordinator (ZC): The ZC sets up the Zigbee network. The Zigbee Coordinator is responsible for bootstrapping the network and coordinates the actions of the network as a whole. We need one ZC per network, and the role is normally taken by the hub, for example, Philips Hue Bridge. As a user, your coordinator does not have to be a smart hub, but we recommend it. It serves as the central point to our network, where we can set permissions, allow other devices access, and coordinate our Personal Area Network (PAN).
- Zigbee Router (ZR): All Full Function Device (FFD), which are powered, non-battery Zigbee devices, all act as routers to repeat the Zigbee signal unless configured to perform another function. This is the default configuration for most Zigbee smart plugs, lights, etc. We can say Routers are in charge of talking to all other devices in range on the network and they “repeat” the network signal. It is like playing Telephone, except Zigbee is actually really good at the game. As long as our devices can “hear” each other, they’ll pass the message on perfectly.
- Zigbee End-Device (ZED): We can buy battery-powered, or a reduced function device to function as an end-device. This device does not forward or repeat signals and very simple to use. More importantly, these devices do not talk to each other. Reduced function devices or end-devices only talk to coordinators and repeaters. In most cases, all devices are full-function devices, unless we choose battery-operated devices such as simple switches, wireless lights, etc.
Why Use Zigbee?
Zigbee is not the absolute best home automation technology. Just like every other home automation technologies, Zigbee has its pros and cons.
Nevertheless, it does have a lot to offer consumers.
- Better Remotes: If we have Infrared lights or RF at home, we will be pleased to know Zigbee is much easier and simpler to use. If we do use a remote, we can point it anywhere to activate the connected device. Furthermore, I would recommend a smart hub because of its additional benefits. For example, a smart hub allows us to connect our Zigbee network to the web so that we can use your phone as a remote. Using our phone as a remote will allow us to set up automation and also control our devices when we are not at home.
- Secure: Just like Z-Wave (Zigbee’s primary competitor), Zigbee also uses 128-bit AES encryption keys. Using the 128-bit AES encryption keys plus short-range signals make Zigbee more secure by default. On the other hand, most home automation protocols have similar levels of security when we configure them properly.
- Stable Networks: Zigbee devices re-route automatically when one device in the network goes off. Our network won’t go down because we accidentally physically turned the hallway light off unless that light is the single link between our network and the rest of the devices in the house.
- Device Interaction: One major feature of Zigbee is that all its devices can talk to other Zigbee devices, with forwards and backwards compatibility. However, not all Zigbee devices are interoperable without a hub.
- Connect to the Cloud: Zigbee links to the Internet over a smart hub. With hubs, we can control devices with apps on mobile, cloud, or desktop devices. It also means setting up automation, collecting usage data, and the option to invite multiple users who will be able to control the same devices.
- Power-Efficient: Zigbee devices are known to be power efficient because they use very little energy when in standby. This enables the device to greatly reduce electric usage and improves battery life where relevant.
- Multi-Device: With support for many devices on a single network, we will never need more than one Zigbee hub. If we only want a few devices, you may need a Zigbee repeater or a different protocol if you’re spreading your smart devices over an entire house.
- Cost-Effective: One of the additional benefits that come with Zigbee is that the devices are very affordable. Zigbee devices tend to be 21-50% cheaper than Z-Wave devices. However, if we are buying a smart device that supports multiple protocols, we will see no real price difference.
Although Zigbee has a lot to offer to its users, at the same time, it also has some drawbacks or issues and they include:
- Zigbee networks have a limited range if we don’t add on more devices.So it is compulsory that a Zigbee device must be within 10-20 feet of another Zigbee device at all times.
- We always need a hub like Homey to pair Zigbee to our computer or mobile phone.
- One of the drawbacks of Zigbee is that not every smart device supports it. While Zigbee dominates the smart light market, we are very likely to need another technology if you want switches, sensors, or data streaming devices.
Zigbee is very common in the smart light industry, but not as common in others. It has a lot to offer for nearly everyone, whether we are a smart home veteran or just looking into your first smart lights. In addition, many major smart home brands feature Zigbee support. Check out their website for more information.