Publish/Subscribe Mechanism for IoT: A Survey of Event Matching Algorithms and Open Research Challenges

The number of sensors getting deployed around the world is increasing due to emergence of Internet of Things. It provides advanced connectivity and communication between devices which goes beyond machine-to-machine communication. Huge amount of data is expected to be generated from different locations that will be aggregated, processed and forwarded very quickly. Publish/Subscribe mechanism is powerful way to allow IoT devices to connect and communicate with each other. One of the major bottlenecks in using Publish/Subscribe systems is the efficiency of filtering incoming message. This is a very challenging problem because in a Publish/Subscribe system the number of subscriptions can be very large. There are quite a few event matching algorithms proposed in the literature to improve its efficiency. The aim of this research paper is to study and analyze how existing approaches ensure fundamental event matching requirements and discuss the open challenges and future work in the area.