Mastering Internet of Things

Propagating information

Consumers that want to discover things register with the same thing registry. Depending on the type of registry used, consumers can find their corresponding things in different ways. There are two principal types of methods available, for the propagation of information about things registered with the registry: event-based methods and search-based methods.

Event-based methods are typically based on the Publish/Subscribe communication pattern. Things register their existence by publishing information about themselves on a topic. Consumers of devices subscribe to relevant topics and get informed about the existence of devices through events on the corresponding topics. The topic tree becomes tightly coupled with the ...