Wireless mesh networks were originally developed for military applications. Compare to other network topology, mesh network require more processing power in each device. However, as data processor cost is reducing drastically over the years, we see mesh network being used in smart home system. Z-Wave and Zigbee are smart home systems that implemented the mesh networks topology.
Typical house structure in Singapore, such as HDB apartment, condominium or landed property, there are many internal concrete partitions. Such structure becomes adverse to wireless communication. Home dweller experience weak WiFi signal at certain spots in their house even the direct distant between their PC (or device) to the router is just within a few meters. Mesh network topology is particularly useful in such environment.
Each node (device) in the mesh networks can relay messages using a routing technique. A node that could not be reached by the controller, the message is relay through an intermediate node. In the illustration below, when there are too many obstacle between the master bedroom toilet switch (node B) to the Z-Wave controller (node X), the control signal could flow through the master bedroom light switch (node C).
Z-Wave’s mesh networking allows a control signal to “hop” (relay through an intermediate node) 4 hopes to reach the final destination. With this capability the maximum coverage range could roughly reach 600 feet or 200 meters.
To ensure all its paths’ availability, the network must allow for continuous connections and must reconfigure itself around broken paths. Z Wave has the ability of self-healing algorithms to maintain and renew its routing table when a node breaks down or when a connection becomes unreliable. As a result, the network is typically very reliable, as there is often more than one path between a controller and a destination in the network.