The Zigbee protocol is an open wireless specification created by the Zigbee Alliance that standardizes how low-power wireless IoT networks can communicate securely and reliably.
Zigbee Standard: The Zigbee Alliance developed the Zigbee standard by adding a network layer, a security layer and an application framework on the top of IEEE 802.15.4 standard.
Zigbee 3.0: The Zigbee Pro specification adds new features such as child device management, improved security, and new network topology options.
Zigbee devices seamlessly form a mesh network, enabling efficient data backhaul through a central node connected to a gateway for remote Internet access. A Zigbee app allows a user to control smart devices from anywhere. Zigbee is built on the Physical layer and Medium Access Control sub-layer defined in the IEEE 802.15.4 standard which manages low-level network operations. The Zigbee Network layer manages the network structure, routing and security. The application layer includes the Application Support sub-layer, the Zigbee device objects and user-defined applications.
Zigbee stackdiagram
Advantages of Zigbee 3.0 Protocol
Zigbee network standardization ensures that all products and services will work together. The standard combines testing, certification, branding and marketing to support the development and sale of interoperable products and solutions.
The latest Zigbee protocol, the Zigbee Pro 2023, adds security enhancements and support for bands beyond 2.4 GHz. The 800 MHz frequency for Europe and the 900 MHz frequency for North America and Australia improves signal strength and range for broader use.
Features of Zigbee Include:
Flexibility — Supports multiple network topologies such as point-to-point, point-to-multipoint and mesh networks
Low-duty cycle — Provides long battery life
Low latency — Can easily transport sensor data with minimal latency
Scalability — Includes Direct Sequence Spread Spectrum (DSSS) up to 65,000 nodes per network
Robustness — Employs collision avoidance, retries and acknowledgments
Low power consumption — Zigbee devices can operate for several years on a single inexpensive battery thanks to its use of a power-saving feature called “sleep mode”
Low data rate — With a data rate of up to 250 kbit/s, Zigbee is best suited for intermittent data sensor or device transmissions
Security — Zigbee security uses 128-bit AES encryption as well as many additional security techniques.
Zigbee Wireless Security
Cryptography within the Zigbee specification is based on the use of 128-bit keys and the AES encryption standard. Encryption, integrity, and authentication can be applied at the Application, Network and MAC layers to secure the frames at each of those levels. Zigbee Pro 2023 provides enhanced security features for protecting the network during device onboarding and operation.
Protocol Compatibility
By design, Zigbee is backward and forward compatible to ensure interoperability. Some compatible devices include Samsung SmartThings, Amazon Echo Plus and Echo Show, Belkin WeMo, Philips Hue, Yale smart locks and other manufacturers that ensure their products support new features.
Over-the-Air (OTA) Software Upgrade Feature
The Zigbee Over-the-Air (OTA) software upgrade feature is a powerful method for using a single device to update the firmware on all other network devices. Manufacturers can use this method to ensure customers are always running the latest and most secure version, improve firmware and even add features to products.
Common Wireless Applications for Zigbee
With low latency and support for many devices, Zigbee works well for home automation, industrial control, and sensor networks. Zigbee can also cost less for manufacturers to build with because there are no license fees or royalties. Here are some prominent use cases:
Green tech applications – Zigbee mesh is an excellent choice for green technology applications such as solar and wind farms and EV charging networks.
Smart home – In a smart home, a Zigbee network can control lights, door locks, smoke detectors, fans, appliances and more. In fact, Zigbee is employed by most large smart home ecosystem providers, including the Amazon Echo Plus, Samsung SmartThings and Signify (formerly Philips Lighting). Worldwide, there are hundreds of millions of Zigbee products in smart homes and buildings.
Smart energy – Zigbee devices built to Zigbee Pro 2023 specifications can now share the same network as Smart Energy devices to improve the control and use of these devices.
Medical – In a medical scenario, a patient can wear sensors that collect and communicate vitals such as heart rate, blood pressure and blood glucose levels wirelessly to a hospital.
Industrial automation – Inside a building, Zigbee can be used to automate lighting control, HVAC, security and access control systems.