Why do we need an event model? Many RDF streaming systems discussed have little or no model for the real-time data they ingest. These systems make the lowest common assumptions about the structure of the data, i.e. that the data consist of a stream of RDF triples. Thus, each piece of real-time data (event) is one triple. One triple, however, cannot hold a lot of information. For example: flexibility in timstamping (one vs. two timestamps or application time vs.
There are several approaches to modelling access control using RDF. The approaches use RDF as a modelling language for permissions linking users with user's rights on the one hand and on the other hand are used on RDF data granting access to users (linking permissions with data). All approaches grant access to RDF resources while assuming what is not granted is forbidden.
"In many event processing systems [...] events are immutable"1. This stems from the definition of what an event is: "An event is an occurrence within a particular system or domain; it is something that has happened, or is contemplated as having happened [...]"2. So events cannot be made to unhappen.