An OPC UA Multi-Server Aggregator with Cache Management

OPC UA (Object Linking and Embedding for Process Control Unified Architecture) has drawn extensive attention in Industrial Internet of Things (IIOT), for it enables secure data exchanges between different operating systems and devices. In the field of industrial control, the applications of OPC UA are gradually extended to the field layer, which adopt the popular client-server interaction model. However, as the number of underling servers increases, the management of the upper layer becomes more difficult. Moreover, there are few kinds of software supporting OPC UA multi-server aggregation currently and they lack effective cache management capability. In order to solve these problems, we design an OPC UA multi-server aggregator with cache management, which enables centralized management of underlying data. Test results show that the proposed aggregator effectively improves the communication efficiency.