Journal of Electronic Systems Niki Pavlopoulou, Edward Curry 10 3 2020 https://doi.org/10.6025/jes/2020/10/3/83-94 http://www.dline.info/jes/fulltext/v10n3/jesv10n3_1.pdf In the last few years, there is an increase of IoT applications in several areas including smart homes, smart cites and so on which ensure entity-based data streams and work on real-life. While the utilization of the resources is assured, these applications need more notification services to users. Some of these needs can be given by the Publish or Subscribe systems; however, the alternative smart systems can reinforce such systems. They can able to increase the reliability or usability and overcome redundancy awareness. In this research we intend to create a boundary for entity centric Publish or Subscribe systems and work for data fusion and top-k diverse ranking. We experimented our system and found that the top-k fused diverse summary yielded better results than separate notifications and without top-k filtering. The top-k fused diverse summarisation scores well in the testing and an acceptable F-score is arrived. The inferences came at the expense of higher latency and there is some equation lies between latency, the number of forwarded messages, and expressiveness.