A Real-Time and Reliable Forwarding Scheme of Publish/Subscribe System

Topic-based publish/subscribe system is widely used in IoT (Internet of Things), but many existing systems cannot work efficiently and flexibly as they ignore the importance of practical factors, such as topic relationship, operating limits and so on. In view of this, we are devoted to improve real-time and reliability of topic-based publish/ subscribe system during forwarding. To improve the real-time performance, we use tree-structure topic clusters to save memory and make the system more flexible. Establishing a policy repository to store policy items and referring to it before transmitting messages can improve the expansibility of system since publishers may make policies for topics they have published to limit subscribers´ operations. In order to improve forwarding reliability, we use feedback mechanism to adjust the transmission speed and keep the proportion of messages with different priorities.