Agreement technologies aim at developing techniques that enable software components to reach agreements on the mutual performance of services, hence supporting the development of large-scale, open distributed systems. Hence, agreement technologies propose a new paradigm for next generation distributed systems. The new paradigm is structured around the concept of agreement between computational agents. These agreements must be consistent with the normative context where they are established and permit, once accepted, that agents call for mutual services and honour them. An entity, by the fact of being autonomous, may choose whether to fulfil an agreement or not, and it should fulfil them when there is an obligation to do so derived from the standing agreements. Autonomy, interaction, mobility and openness are the characteristics that the paradigm covers from a theoretical and practical perspective. We have identified negotiation, semantic alignment and trust as the key enabling agreement technologies.
- Negotiation techniques allow agents to reach agreements on the terms of their interactions.
- Semantic alignment techniques allow agents using different ontologies to understand one another.
- Trust is the technology that complements traditional security mechanisms by relying on social mechanisms that interpret the behaviour of agents.
Agents are computer programs that have: autonomy, they chose their course of action without human intervention; proactiveness, they pursue their own goals; and reactiveness, perceive their environment and react to sudden changes on it. We have been working on the social aspects of agents when they interact through dialogues, in the area of automated negotiation. We have developed:
- Infrastructures for agent mediated auction houses, that is, virtual places on the network where agents meet to sell and buy goods acording to particular auction protocols.
- Techniques for agent mediation when the dialogue between agents corresponds to a multi-issue negotiation protocol.
- Reputation measures as a mean to evaluate the credibility of agents when engaging on negotiation.
- Argumentation techniques as a means for negotiation, that is, to complement offers and counteroffers on negotiation with promises, threats or enticements of different sorts, in order to persuade the others about a particular course of action.