Abstract

Slides: available.

Event-based systems are very useful when event producers, consumers, and processors are distributed, perhaps hosted by different entities where each is its own administrative domain. In the past we have advocated deontic logic to express policies that govern the sharing of data between such entities. Last week David Eyers introduced the DEF Con model which can provide information flow control within one organisation. Here I will present some ideas about extending this across organisation boundaries, including how one might interpret security tags (and labels) in this context, how tags and labels relate to deontic agreements between organisations, consequent influence of tagged event transmission on the state of compliance, and what an implementation within SBus might look like.