ZigBee is a wireless mesh network built on IEEE 802.15.4 standard. With the advancement in sensors and low-powered smart devices, there was a need for a technology that can connect them wirelessly in the form of a mesh. The ZigBee technology was introduced which works on a Personal Area Network and works on low power. Internet of Things searches for the technology with low power consumption because it is built with the devices with limited power capabilities. For that purpose, ZigBee is considered as a technology with a seamless connection flexibility, ideal power consumption, and reliability.

ZigBee gives a 10-100m line of sight coverage for connectivity. Typically, it works on a 2.4 GHz band (ISM) but can be found on other frequency like 784 MHz, 868 MHz, and 915 MHz. With the wide variety in the spectrum, the data rates in ZigBee varies from 20 Kbit/s to 300 Kbit/s. The ZigBee module can be of 0.5 inches which are easily implementable in any Internet of Things device. One of the attractive parts of ZigBee is that it has out of the box capabilities of wireless mesh, star and tree architecture:

A significant disadvantage of ZigBee lies in its adoption in computing devices. Typically, a smartphone or a laptop does not come with this module. Computers and cellular phones are the basic connection points for IoT devices. For example, if a person has ZigBee-based smart-home device, he will not be able to control it with his cellular phone or laptop without connecting additional hardware. This is a very crucial disadvantage as IoT devices mostly, if not always, rely on a smartphone-based remote control. Philips Hue (a smart bulb) can not be remotely controlled by a smartphone if its major technology of communication is ZigBee.

This disadvantage leaves a question mark on the technology but the other side can not be neglected as well. ZigBee is the only lite-weighted-low-power-consumption technology available in the market which supports mesh communication out of the box. Companies like smart plugs and smart energy interface use ZigBee as their main mode of communication. Let's take the example of Philips Hue Wireless dimming kit. It comes with a separate controller which talks to the smart bulb without any need of the smartphone. In this scenario, ZigBee can be the most practical solution.

A demonstration of the Philips Hue smart bulb can be seen here: