Hierarchical Topic Aggregation for Geospatial Applications through Processing Extensions in Message Brokers

Publish/subscribe (pub/sub) message brokers are typically operated with multiple tenants and multiple topics per tenant. Messages sent by a producer to a topic are received by consumers who subscribed to the same topic. In many applications, topic hierarchies are a desired property. This is especially the case for geospatial applications in which regions are composed of smaller-scale regions. However, most message brokers do not support hierarchies natively. HTABroker demonstrates how a light-weight processing function deployed to an extensible message broker overcomes this limitation for several geospatial index systems.