RFZigbee 3.0: Features, Protocol Stack, and IoT Applications
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This Zigbee 3.0 tutorial covers its features, protocol stack, and benefits in IoT (Internet of Things) applications.
About Zigbee 3.0
Zigbee 3.0 is a significant evolution of previous Zigbee standards. It’s primarily designed to enable seamless interoperability among diverse application profiles. This means Zigbee 3.0 allows devices from different application areas to communicate and form a single, unified network.
For example, a smart bulb using the Zigbee Light Link profile can seamlessly coexist and interact with a sensor from a healthcare profile within the same Zigbee network. Furthermore, Zigbee 3.0 compliant devices support connectivity with IP networks like LANs and WANs, making them ideal for IoT networks. This allows products from different manufacturers to communicate as a single, cohesive network.
Zigbee 3.0 is based on the IEEE 802.15.4 standard and operates on the 2.4 GHz global frequency band, utilizing the Zigbee PRO version.
Key Features of Zigbee 3.0
- Low Power: Zigbee 3.0 devices are designed for low power consumption and low data rates. This is crucial for IoT devices requiring long battery life.
- Reliable and Robust: Zigbee 3.0 supports mesh topology. This eliminates single points of failure, ensuring reliable packet delivery across the network.
- Scalable: Devices can be easily added to a Zigbee 3.0 network at any time, providing excellent scalability.
- Secure: It utilizes AES-128 encryption, making it a secure network.
- Global Standard: Operating in the 2.4 GHz frequency band, Zigbee 3.0 enjoys widespread global adoption.
These features clearly illustrate the advantages of Zigbee 3.0 compared to earlier versions.
Zigbee 3.0 Protocol Stack
Figure 1 illustrates the Zigbee 3.0 protocol stack, consisting of the PHY, MAC, network, and application layers. The primary changes in Zigbee 3.0 compared to previous versions are concentrated in the application layer.
The network layer sits between the application layer and the PHY/MAC layers, as defined in the IEEE 802.15.4 standard. Zigbee 3.0 incorporates a Zigbee Base Device Behavior layer to ensure consistent behavior when commissioning new nodes.
Zigbee 3.0 Network Security
The security layer is enhanced in Zigbee 3.0, supporting two security modes:
- Centralized: This mode is managed by a central coordinator responsible for network formation and key assignment to new nodes.
- Distributed: This mode lacks a central coordinator. The Zigbee router manages network establishment and key assignment to peer routers.
Figure 3 illustrates these Zigbee network security modes.
Additional Benefits of Zigbee 3.0
- Supports a large number of nodes (up to 250).
- Accommodates the dynamic nature of networks.
- Supports rejoining of orphaned nodes with new parent nodes in case of parent loss.
- Provides backward compatibility with other Zigbee application profiles, such as Zigbee Light Link 1.0 and Zigbee Home Automation 1.2.
