Event-based Software Architectures1

Implementation architectures of today are based on the modularisation of software into objects, components, web services, (intelligent) agents, ... with communication and coordination between components being based on peer-topeer communication (a client-component requests a service from a servercomponent). Because this binary and uni-directional form of communication implies substantial restrictions on software maintainability, this paper proposes the development of a new N-ary and multi-directional communication paradigm based on the notion of "event": components will interact by jointly participating in events. This new communication paradigm uses event broadcasting as a coordination mechanism between software components. It can be implemented by means of generic binary interaction frameworks applicable across diverse platforms (distributed, web-based and centralised systems) and implementation paradigms (synchronous and asynchronous communication).. In addition, events can be enriched with intelligent features so as to be able to act autonomously and to be capable of undertaking some rescue actions when one of the composing actions fails.