Transactional Reduction of Component Compositions

Abstract

Abstract. Behavioural protocols are beneficial to Component-Based Software Engineering and Service-Oriented Computing as they foster automatic procedures for discovery, composition, composition correctness checking and adaptation. However, resulting composition models (e.g., orchestrations or adaptors) often contain redundant or useless parts yielding the state explosion problem. Mechanisms to reduce the state space of behavioural composition models are therefore required. While reduction techniques are numerous, e.g., in the process algebraic framework, none is suited to compositions where provided/required services correspond to transactions of lower-level individual event based communications. In this article we address this issue through the definition of a dedicated model and reduction techniques. They support transactions and are therefore applicable to service architectures.

Event strictness for components with complex bindings

“…Usually an event can be explicitly hidden, or conversely, be made visible outside and can be synchronised with other events. But, hidden events are not completely transparent from a behavioural point of view, see [21] for a related point of view. We think it makes sense to have a finer model which distinguishes hidden events, events visible for verification purposes and events exported for further outside connections.…”

“…For instance, we get a unique event label and it is difficult or impossible to know the exact activity of each subcomponent involved in an interaction [14]. We also expect to keep the names of the events, since they are not completely transparent from a behavioural verification point of view, for instance [21] and AltaRica [8] have taken similar choices. To get simpler behaviours, one can abstract away some of this information to build a strict STS or even a classic LTS if needed.…”

Model-Based Adaptation of Behavioral Mismatching Components

“…Moreover we would like to specify a correspondence between the video sending (video in ROOM) and the mpeg file reception (mpeg in PDA), and a correspondence between the text sending (text in ROOM) and the pdf file Vectors express correspondences between messages, like bindings between ports, or connectors, in architectural descriptions [22]. Yet, vectors alone are not sufficient to perform adaptation as one must take into account also the February 1, 2008 DRAFT context in which messages are exchanged, i.e., the component protocols.…”