PERCHE: A Public Registry for Choreographies

When Web Service composition takes place in an open environment, involving services that belong to different organizations, a choreography-level registry can play a major role. Such a registry acts as a “mediator” between companies providing individual services and companies providing complex business models as choreographies. We propose a framework, called PERCHE, that supports the management of public registries for choreographies: when a provider aims at offering a complex service which involves the cooperation of different participants (roles), it publishes the choreography specification onto the registry. The choreography (global view) is splitted into the interaction protocols of the individual roles (local views). To join a choreography, a company applies for a specific role, by providing an implementation of the corresponding interaction protocol. We present the architecture and functionality of the PERCHE framework, discussing the relations between global and local views, briefly facing the issue of the choice of a suitable choreography language, and providing an example, to show how a registry based on the PERCHE framework works.