Chinese augmented reality firm WiMi Hologram Cloud has developed a fog architecture for IoT sensing and actuation-as-a-service (SAaaS).

The main goal of this scalable and fault-resistant layered fog architecture is to enhance the SAaaS performance of IoT by introducing a failure-resistant layer of fog nodes between the cloud and IoT devices. This architecture is referred to as a multi-layer architecture.

WiMi’s layered fog architecture can be called sensor and actuator service layered fog delivery. It is more fault-resistant and maintains network connectivity by dynamically reassigning tasks from the failed node to the nearest active node. The architecture keeps track of user-pre-specified instructions. These instructions are closer to the end-user IoT device terminals, speeding up the generation of drive commands. In the case of overload, such nodes can offload their monitoring responsibilities to their parent nodes.

This fog architecture can operate under a diverse ecosystem and properly manage observation and drive requests. In addition, its infrastructure is virtualised, allowing multiple users to use the same physical layer components simultaneously, thereby reducing service costs.

Fog computing is leveraged to handle some IoT and cloud tasks that are geographically closer to the data source rather than relying exclusively on remote cloud data centres. Due to the high volume of sensed data generated by IoT sensors, fog nodes can be overloaded. To avoid delays in driving command generation, the architecture monitors user-specified situations in the fog layer and allows each fog node to offload monitoring to its parent when overloaded, preventing fog nodes from overloading to reduce action latency.

WiMi establishes multi-layer fog nodes between the cloud and IoT devices in SAaaS, which enables dynamic fault feedback schemes. The failure of information sending and feedback is avoided by reassigning the task of the faulty fog node to the nearest connected fog node in the same layer or to the parent node of the faulty node.

WiMi compares the number of lost messages for SAaaS with and without layered fog (fault redistribution, pre-specified situations in fog nodes and offloading) based on computation and communication latency and observation and drive commands in different scenarios such as number of users, sensors, actuators and zones by using a fog simulator for evaluation.

Redistribution in case of failure prevents lost messages and maintains network connectivity, improving fog applications’ security, stability and response rate.

WiMi Hologram Cloud is a holographic cloud technical provider that focuses on professional areas including holographic AR automotive HUD software, 3D holographic pulse lidar, head-mounted light field holographic equipment, holographic semiconductors, holographic cloud software, holographic car navigation and others.