Towards a flexible middleware negotiation facility for distributed components

In today\´s environment of global competition/cooperation, distributed organizations often form alliances to improve their ability to accomplish their customers\´ requests. The paper concerns such alliances alliances with loose relations between peer autonomous organizations that allow them to negotiate services, especially with a view to outsourcing work that they cannot perform alone. We are working on a platform that aims at providing support for the design of such alliances, letting their members flexibly negotiate services, make informed decisions and consistently enact contracts. The platform is built according to a multitier approach, where the lowest layers are concerned with pure communication issues between abstract entities (agents, objects, components) and the highest layers are concerned with the actual entities that form the application (i.e. the alliance). In this paper we focus on an intermediate layer, the "middleware" layer which aims at addressing general, domain-independent requirements on the interaction infrastructure to support negotiation. In particular, we describe here the lowest part of the middleware, namely a communication protocol to be used in the implementation of multiparty, multi-attribute negotiation. We illustrate this protocol through an example in the domain of negotiations of print jobs across distributed printshops