The smart home has taken hold for good. The creation of home networks (PAN – Personal Area Networks) has become a standard because almost everyone today has solutions at their fingertips that improve the comfort and economy of the home: controllers, sensors, intelligent relays and temperature controllers.
The devices operating in the home must work quickly, in interconnection (scenarios, rules, scenes). That is why manufacturers of new technologies are offering customers ever better tools to build links between home appliances.
However, in order for devices to communicate wirelessly, they need a suitable data transmission path, a so-called communication protocol. For example, one such as ZigBee.
ZigBee is a wireless data transmission protocol used for two-way communication between devices. The two-way communication means that each device can both receive and send a signal.
The system was created in 2002 by the ZigBee Alliance, which is still involved in its development and promotion. The main features of this communication standard were to be low power consumption and simple, low-cost design. And this has been achieved. Many well-known technology brands work with the ZigBee Alliance.
In fact, it is difficult to imagine a smart home without ZigBee technology. It is used to manage devices that simplify the daily use of the home (control of lighting, blinds, heating), but also to increase security (sensors, alarms).
It is not just a matter of operating devices remotely, but of creating user-defined connections between them. For example, when a sensor detects that a door has been opened, a signal is sent out, which causes the lights to switch on, the shutters to close and the temperature to rise. This happens automatically, without human intervention – once programmed, devices send each other signals to ‘act’ depending on the status of other devices. Modern building automation is based on scenarios that the user creates himself, guided by his own needs.
The ZigBee communication protocol was developed for home networking (PAN) and is very well suited for this. Its main advantages are:
A ZigBee home network can be organised according to three typologies: star, tree, and mesh. The idea is that the elements working in it – the Internet gateway (coordinator), the final actuators – should implement the communication pattern well, and therefore fulfil their role in the automated home.
A simple typology applied to Bluetooth, for example. The coordinator is a single device (master) and all others are subordinate (slave) to it – they communicate directly with the coordinator and only with it.
The typology has a hierarchical arrangement. The coordinator is the ‘root’ and manages the ‘branches’. Each branch has subordinate elements. The end devices (executors) can only be at the end of the branch, they do not communicate with others. They only execute “commands”. In this schema, transmission delays are most common.
The mesh typology is not hierarchical. Here, each device can communicate with another – either directly or via an intermediary device. This feature improves the functionality of the system, which is why it is considered the best type of ZigBee network organisation.
ENGO Controls’ technology is based on a mesh typology: after installing the Internet gateway, it is necessary to install the voltage-powered devices (they simultaneously become the network repeaters) and finally the battery-powered devices. This ensures that communication between all components is fast, smooth and reliable.
Devices in the ZigBee standard are coordinated by the gateway, which links them into a coherent system in the home network. However, with the online control option, it is also the link between the home network and the outside world. In combination with the ENGO Smart mobile app, the gateway enables home control from anywhere.
Wi-Fi (Wireless Fidelity) is a wireless communication method used worldwide. It is used both in PAN (home) networks and in all public places.
ENGO Controls also offers products that use the Wi-Fi protocol.
First of all, it consumes more power. Besides, ZigBee creates a mesh of connections between devices, extending the range of the network. Each powered device emits a signal, increasing its limits. With Wi-Fi, additional repeaters are needed to extend the range of the network through the mesh.
And, crucially, a network built on ZigBee retains its links even if, as a result of a fault or anything else, internet connectivity disappears. With Wi-Fi, the absence of Internet means that the built-up working rules (dependencies, scenarios) immediately cease until it is restored.
In contrast, both standards outclass Bluetooth technology in terms of range – here the range is incomparably lower. Power consumption is also low, but data transfer requires communication with another device supporting this protocol. Bluetooth is mainly used in portable devices – for ad hoc tasks (e.g. transferring a photo from a phone to a phone).