In the rapidly evolving world of wireless communication, the Wi-SUN (Wireless Smart Ubiquitous Network) technology stands out for its ability to support large-scale, low-power, and high-reliability mesh networks. Establishing a large Wi-SUN test network in the lab is crucial for understanding its capabilities and optimizing its performance for real-world applications. This blog delves into the goals of setting up such a network and the key performance measurements that help evaluate its effectiveness.

Silicon Labs proudly maintains a one-of-a-kind, extensive in-house sub-GHz Wi-SUN FAN test network, committed to thorough and rigorous testing. Building on our previous implementations of large Zigbee and Z-Wave mesh networks, along with hundreds of Bluetooth Low Energy (LE) nodes for ESL testing, we’ve gained invaluable insights that have shaped our current Wi-SUN test network. Featuring 1,000 sub-GHz mesh nodes, the network showcases our commitment to advancing wireless communication technologies. By leveraging these diverse experiences, Silicon Labs continues to innovate and provide cutting-edge solutions for a seamlessly connected world.

Goals of a Large Wi-SUN Test Network

The primary objective of creating a large Wi-SUN test network in the lab is to gain customer confidence by showcasing a robust internal network of this size. This makes it possible to test behaviors and features on a real-world-sized network. Performance evaluation is a critical aspect, as it involves assessing the network's performance under various conditions to ensure it meets the required standards and SLAs (Service Level Agreement) for latency, connection time, and scalability. Reliability testing is equally important, ensuring the network can maintain stable connections and handle data transmission efficiently, even in challenging environments.

Scalability analysis is another key goal, as it helps us understand how the network performs as the number of connected devices increases. This is essential for applications like smart metering and street lighting. Battery life optimization is also a priority, as we need to evaluate the impact of network operations on battery life to ensure devices can operate for extended periods without frequent recharging. Lastly, interference management is crucial for testing the network's ability to coexist with other wireless technologies and minimize interference.

Wi-SUN Network Testing: Performance Measurements

To achieve these goals, several key performance measurements are implemented. Latency is measured to determine the time it takes for data to travel from one point to another within the network, including round-trip latency tests using IPv6 ping capabilities. Connection time is evaluated to see how quickly devices can join the network and establish stable connections. Packet error rate is assessed to understand the frequency of errors during data transmission, which impacts overall network reliability. Routing metrics are analyzed to evaluate the efficiency of the Routing Protocol for Low-Power and Lossy Networks (RPL) in managing data paths and ensuring optimal routing. Finally, scalability is tested by focusing on maintaining low latency and high reliability as the number of connected devices increases.

Implementation of a Wi-SUN Test Network

The implementation of the Wi-SUN test network involves several critical components. A node monitoring application is embedded in nodes, which transmit data every five minutes. A graphical user interface (GUI) allows for the visualization of behavior, connectivity, and availability. Typical features being implemented include a direct connect tool, which allows a device to get connected to a node to debug or recover information. The pan_defect feature involves a battery-backed border router (BR) informing the nodes that it is going to die, prompting nodes to switch over to another BR. The preferred pan feature allows the load between Border Routers and enables nodes to return to the preferred BR after failure.

What’s Next for Wi-SUN Testing?

Future implementations will prioritize low-power limited function nodes (LFNs), commonly referred to as leaf nodes, which primarily operate on battery power. By integrating both line-powered devices and battery-powered sensor nodes, the test network will be capable of evaluating more complex configurations and ensuring the seamless operation of a unified system.

Benefits of a Wi-SUN Lab

Setting up a large Wi-SUN test network in the lab is a critical step in advancing wireless communication technologies. By thoroughly evaluating performance metrics such as latency, connection time, packet error rate, routing efficiency, and scalability, researchers and developers can optimize Wi-SUN networks for various applications. This ensures that the technology remains robust, reliable, and ready to meet the demands of modern smart infrastructure.